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EMD SD70 series
Norfolk Southern SD70 No. 2562
Type and origin
Power typeDiesel-electric
BuilderElectro-Motive Diesel (EMD)
ModelSD70, SD70I, SD70M, SD70M-2, SD70AC, SD70MAC, SD70ACe, SD70ACe/LCi, SD70ACS, SD70ACe-T4, SD70ACe-BB, SD70ACe/45, SD70IAC, SD70ACe/LW, SD70ACe-P4, SD70ACe-P6, SD70ACU, SD70ACC, SD70MACH, SD70MACe
Build date1992–present
Total producedSD70: 122
SD70I: 26
SD70M: 1,758
SD70M-2: 363
SD70MAC: 1,154
SD70ACe: 2,134
SD70ACe/lc: 205
SD70ACS: 86
SD70ACe-P4: 80
SD70ACe-P6: 50
SD70ACe-T4: 176
SD70ACe-BB: 64
SD70ACe/45: 537
Specifications
Configuration:
​
 • AARC-C (B+B-B+B for SD70ACe-BB, B1-1B for SD70ACe-P4 and SD70MACH)
 • UICCo'Co' (Bo'Bo'Bo'Bo' for SD70ACe-BB, Bo1’1Bo’ for SD70ACe-P4 and SD70MACH)
 • CommonwealthCo-Co (Bo+Bo-Bo+Bo for SD70ACe-BB, Bo1-1Bo for SD70ACe-P4 and SD70MACH)
Gauge4 ft 8+1⁄2 in (1,435 mm) standard gauge for the North American market;
1,520 mm (4 ft 11+27⁄32 in) for Yakutia;
1,600 mm (5 ft 3 in) for Brazil;
1,000 mm (3 ft 3+3⁄8 in) for Brazil and Guinea
TrucksEMD HTCR-Ia: SD70, SD70I, SD70M, SD70MAC;
EMD HTCR-Ib: SD70I, SD70M, SD70MAC, SD70ACU;
EMD HTCR-4: SD70M, SD70MAC, SD70ACe;
EMD HTCR-6: SD70ACe, SD70ACe-T4;
EMD HTSC-II: SD70M, SD70ACe, SD70ACe/LCi, SD70ACS, SD70ACe/45;
EMD GBB: SD70ACe-BB
Prime moverEMD 16-710G3 2-stroke diesel;
EMD 12-1010J 4-stroke diesel for SD70ACe-T4
Engine typeV16;
V12 for SD70ACe-T4
Cylinders16
12 for SD70ACe-T4
TransmissionDiesel electric
Performance figures
Maximum speed70 mph (110 km/h), 75 mph (121 km/h) for the SD70ACe-T4
Career
NicknamesVacuum Cleaners (SD70ACe-T4) Thundercabs (Early SD70ACe models)
LocaleNorth America, Brazil, Peru, Guinea, Mauritania, Saudi Arabia, United Arab Emirates
DispositionMany operational, several retired due to wrecks, two preserved (one SD70ACe and one SD70MAC).

The EMD SD70 is a series of diesel-electric locomotives manufactured by Electro-Motive Diesel. This locomotive family is an extension and improvement of the EMD SD60 series. Production commenced in late 1992[1][page needed] and since then over 5,700 units have been produced; most of these are the SD70M, SD70MAC, and SD70ACe models. While the majority of the production was ordered for use in North America, various models of the series have been used worldwide. All locomotives of this series are hood units with C-C trucks, except the SD70ACe-P4 and SD70MACH which have a B1-1B wheel configuration, and the SD70ACe-BB, which has a B+B-B+B wheel arrangement.

Superseding the HT-C truck, a new bolsterless radial HTCR truck was fitted to all EMD SD70s built 1992–2002; in 2003 the non-radial HTSC truck (basically the HTCR made less costly by removing radial components) was made standard on the SD70ACe and SD70M-2 models; the radial HTCR truck remained available as an option.

Models

[edit]

SD70 (1992–1999)

[edit]
Illinois Central SD70 No. 1004

The EMD SD70 typically has the smaller spartan cab, typical on preceding SD60 models, instead of the larger comfort cab used on later models. Notable differences between the SD70 and SD60 are the radial steering EMD HTCR truck instead of the older HTC truck, and the SD70's overall length of 72 ft 4 in (22.05 m), with the older SD60 being 2 inches shorter. The SD70 also rides higher as its frame is approximately 1⁄2 inch (13 mm) higher than the SD60. This model is equipped with direct current (DC) traction motors, which simplifies the locomotive's electrical system by obviating the need for computer-controlled inverters (as are required for alternating current (AC) power). It is equipped with the 4,000 horsepower (3,000 kW), 16-cylinder EMD 710 prime mover. One hundred and twenty-two examples of this model locomotive were produced for Norfolk Southern (NS), Conrail (CR), Illinois Central (IC) and Southern Peru Copper Corporation (SPCC). Conrail's assets were split between Norfolk Southern and CSX in 1999, and all 24 of Conrail's SD70 units went to NS. Other than the CR paint scheme these units were built to NS specifications and numbered (2557 - 2580) in series with Norfolk Southern's already purchased SD70s.

Production of the standard cab at EMD's London, Ontario plant ended in 1999. The 24 Conrail SD70s were assembled from kits at Conrail's Juniata Shops in Altoona, Pennsylvania, while the IC and SPCC SD70s were assembled from kits at Super Steel Schenectady. Most SD70s are still in service with Norfolk Southern and Canadian National (CN), which merged with Illinois Central in 1999. In February 2017, NS began a program to convert its SD70s from DC to AC, which will also have a new wide-nose cab, and several other upgrades. They will be designated as SD70ACC.

SD70M (1992–2004)

[edit]
Union Pacific SD70M No. 4352

The SD70M has a wide nose and a large comfort cab (officially known as the "North American Safety Cab"), allowing crew members to ride more comfortably inside of the locomotive than the older standard cab designs. There are two versions of this cab on SD70Ms: the Phase 1 cab, which was first introduced on the SD60M, and the Phase 2 cab, which is a boxier design similar to the original three-piece windscreen on the SD60M, which is shared with the Phase 2 SD90MAC, SD89MAC, and SD80ACe. The Phase 2 cab has a two-piece windscreen like the Phase 1 windscreen but the design of the nose is more boxy, with a taller square midsection for more headroom.

The SD70M is equipped with D90TR DC traction motors and the 710G3B prime mover.[2][page needed] They are capable of generating 109,000 lbf (480 kN) of continuous tractive effort.[2][page needed] From late 2001, the SD70M was produced with SD45-style flared radiators allowing for the larger radiator cores needed for split-cooling. Split-cooling is a feature that separates the coolant circuit for the prime mover and the circuit for the air pumps and turbocharger. There are two versions of this radiator: the older version has two large radiator panels on each side, and the newer version has four square panels on each side. This modification was made in response to the enactment of the United States Environmental Protection Agency's (EPA) Tier 1 environmental regulations. Also the truck was replaced with HTCR-4, instead of HTCR-I on former model.

Production of the SD70M ceased in late 2004 as production of the SD70M-2 model began (the EPA's Tier 2 regulations went into effect on January 1, 2005). A total of 1,609 SD70Ms were produced. Purchasers included New York, Susquehanna & Western (NYSW; part of EMDX order no. 946531[3]), Norfolk Southern and Southern Pacific, but the vast majority were purchased by Union Pacific.

In 2000, an order of SD70Ms made history when Union Pacific ordered 1,000 units (UP 4000 through UP 4999, inclusive, although 4014 was renumbered 4479 to accommodate Big Boy 4014 in 2019[4]). This order was later extended by nearly 500 additional units (UP 3999 and below, UP 5000 and above, except for 3985, which was left vacant for Challenger 3985).

This locomotive model is also built for export, and is still catalogued by EMD (at 4,300 hp or 3,200 kW). CVG Ferrominera Orinoco has six SD70Ms that were built as an add-on order to UPs FIRE cab equipped SD70Ms. Companhia Vale do Rio Doce (CVRD) in Brazil has ordered 55 of this model for service for the Carajás mine pulling trainloads of iron ore. Since CVRD track is gauged at 1,600 mm (5 ft 3 in), a wider bogie, the HTSC2, was designed for these units by EMD.[5]

SD70I (1995)

[edit]
Canadian National SD70I No. 5619

The SD70I is a version of the SD70 which has been fitted with a cab that is isolated from the frame of the locomotive with rubber gaskets (officially known as a "WhisperCab"). The isolation reduces noise and vibration from the prime mover. A seam is visible across the nose and on the long hood where the cab connects with the body. 26 examples of this model locomotive were produced, all for Canadian National. The WhisperCab feature was incorporated into some SD70MACs and was standard on both the SD80MAC and SD90/43MAC models.

SD70MAC (1993–2007)

[edit]
Alaska Railroad SD70MAC No. 4006 "Spirit of Anchorage"

The SD70MAC uses three phase AC traction motors. Production of the model commenced in 1993, competing against the GE AC4400CW. The majority of SD70MAC models were produced with the 4,000 horsepower (3,000 kW) EMD 710 prime mover while later units are rated at 4,300 horsepower (3,200 kW) and feature EMD SD45-style flared radiators.[citation needed] Starting in 1993, the Alaska Railroad ordered SD70MACs with head-end power to make them suitable for both freight and passenger service; no other railroad ordered this variant. Due to the Alaska Railroad's satisfaction with these locomotives, they specially ordered additional models after EMD had transitioned production to the SD70ACe.The last order of Alaska Railroad SD70MACs was built/delivered in late 2007.[6][7] The trucks were replaced with HTCR-4, instead of HTCR-I on former model.[citation needed][clarification needed]

CSX SD70MAC No. 4761 with SD45-style flared radiators

The SD70MAC is no longer produced due to EPA regulations, and was replaced by the SD70ACe in 2004. In total, 1,109 SD70MACs were produced, purchased by Burlington Northern (and its successor, BNSF), Conrail, CSX, Transportación Ferroviaria Mexicana (TFM; units now owned by Kansas City Southern Railway (KCS)), and the Alaska Railroad.

SD70ACe (2004–present)

[edit]
Union Pacific No. 8505 leads a coal train

The SD70ACe is the successor to the SD70MAC with design changes to comply with emission standards. The engine fires with 15% lower internal pressure to improve emissions and features fewer internal components in the inverter.[8] The SD70ACe is equipped with EMD's 16-710-G3C-T2 prime mover, rated at 4,300 horsepower (3,200 kW); later Tier 3 models are rated at 4,500 horsepower (3,400 kW), and have a thermal efficiency of almost 36%.[9] They are rated at 191,000 lbf (850 kN) starting tractive effort and 157,000 lbf (700 kN) continuous. Braking effort is rated at 106,000 lbf (470 kN). Early models featured a bad cab design which was noticed first on CSX as crews reported annoying disturbances such as prime mover noises, traction motors and more. The cab was also known for rattling, leading to the nickname "Thundercabs". As a result, these units are also not approved for leading trains.[9]

In 2012, EMD also built four models known as the SD70ACe-P6. These units, unlike previous SD70ACe's, have one inverter per axle on the trucks, rather than EMD's traditional one inverter per truck design. Four of those (EMDX 1206, 1208, 1209 and 1210) were sold to Canadian National Railway and renumbered to CN 8100–8103.[citation needed]

In 2014, BNSF took delivery of 20 SD70ACe-P4 units, numbered 8500 - 8519. This model was designed with a B1-1B wheel arrangement to compete with GE's ES44C4 model, which has an A1A-A1A wheel arrangement. Both wheel arrangements mean that there are only two traction motors per truck instead of three, those being the ones next to the fuel tank. Two SD70ACe-P4 demonstrators began a 5-year lease at Tacoma Rail in late 2014, and were later sold to Arkansas & Missouri Railroad in late 2023.

On January 1, 2015, the United States Environmental Protection Agency's Tier 4 locomotive emission regulations went into effect. EMD could not successfully modify the SD70ACe's 2-stroke 710 series prime mover to be Tier 4-compliant; thus, the Tier 3 SD70ACe was succeeded by the SD70ACe-T4 in late 2015. However, US production of the Tier 3-compliant SD70ACe continues with Tier 4 'credit units' (new Tier 3-compliant units EMD is entitled to build based on previously earned emissions credits). Union Pacific and Norfolk Southern are currently the only US roads to own Tier 4 credit unit SD70ACe's. Additionally, EMD has continued building Tier 3 SD70ACe's for Ferromex (4100–4118), Ferrosur (4119–4133), and Kansas City Southern de Mexico (4200–4224) at Bombardier Ciudad Sahagun. These locomotives are restricted to Mexico-only operation and cannot cross the US border (just as Canadian National's newest Tier 3 GE ES44AC's are restricted to Canadian use only).[citation needed]

In March 2016, EMD replaced the standard cast HTCR-4 trucks on NS SD70ACe 1000 with the new fabricated HTCR-6 trucks for testing. UP and BNSF plan to test the new HTCR-6 trucks on some of their SD70ACe units also.

Union Pacific received 281 additional SD70ACe units, numbered 8824 - 9104, in 2014, 2016 and 2018. These are referred to as SD70AH (T4C), H for "heavy", because they are ballasted to 428,000 lb (194,138 kg) rather than 420,000 lb (190,509 kg).

2TE3250 (2021)

[edit]

In mid-2021, the Yakutian Railway received two SD70ACes, designated 2TE3250 (Russian: 2ТЭ3250) by Yakutian Railway itself. These units, numbered 0001 and 0002, are currently in use in Yakutia, and are operated as a two-section locomotive.[10][11]

In November 2021, Yakutian Railway announced a tender for six more, single-section locomotives.[12] However, as of 4 February 2022, it has been unable to make an order for them.[13]

SD70M-2 (2004–2011)

[edit]
Canadian National SD70M-2 No. 8951

The SD70M-2 is a DC traction version of the SD70ACe. The "-2" in the model name indicates that the units are EPA Tier II compliant and that the locomotive has upgraded electronics, which was true for older models (EMD SD40-2).[14] SD70M-2 models are equipped with the 16-710G3C-T2 or 16-710G3C prime mover which is rated at 4,300 horsepower (3,200 kW).[15]

In total, 331 SD70M-2s were built, with Canadian National owning 190 units. Eight units owned by Electro-Motive Diesel and four units owned by CIT Financial were leased by Florida East Coast Railway until early 2015. Canadian National 8964 was the last SD70M-2, built in February 2011. Vermont Railway owns 2 units numbered 431 and 432. Norfolk Southern ordered 130 SD70M-2s, of which 46 remained in service as of July 2023 with 2 units rebuilt with AC traction.[16][17][18] Currently, NBM Railways owns 13 SD70M-2, former NS units, numbered 6401–6413 with plans for six more rounding it out to 6419. All are marked for the various NBM companies, New Brunswick Southern Railway, Eastern Maine Railway, and Maine Northern Railway.

SD70ACe-T4 (2015–present)

[edit]
Union Pacific SD70ACe-T4 No. 3032

The SD70ACe-T4 is the Tier 4 emissions standards-compliant successor of the SD70ACe. The first locomotive, EMDX 1501, was built in summer 2015, and made its debut at the Railway Interchange Expo in Minneapolis, Minnesota during the weekend of October 3–4, 2015. It features a new 4-stroke engine called the EMD 12-1010 "J" series - a V12 with 1,010 in3 displacement for each cylinder. This new prime mover has a two-stage turbocharger system consisting of three turbos; one turbo (the primary/high pressure turbo) for low-mid RPM and two turbos (the secondary/low pressure turbos) for mid-high RPM. The results of this setup are higher power throughout a broader RPM range, better fuel efficiency, and lower emissions. An EGR system is applied as well, allowing the engine to achieve Tier 4 without the use of urea aftertreatment. Another new feature of this engine is the Double-Walled Fuel Injection System that increases safety and provides simplified maintenance works.

The EMD 12-1010 is capable of producing 4,600 horsepower (3,400 kW) total, 4,400 horsepower (3,300 kW) is used for traction.[19] With a new computer software for the on-board computer and one inverter per axle (or "P6"; EMD named it "Individual Axle Control") - unlike most of previous EMD locomotives that use one inverter per truck, the SD70ACe-T4 is capable of generating 200,000 pounds-force (890 kN) of starting tractive effort, and 175,000 pounds-force (780 kN) of continuous tractive effort. Meanwhile, its dynamic braking effort is as much as 105,000 pounds-force (470 kN). The amount of starting tractive effort is equal to that of the 6,000 horsepower (4,500 kW) SD90MAC-H while, on the other hand, its continuous tractive effort is higher than that of the SD90MAC-H (175,000 pounds-force (780 kN) vs. 165,000 pounds-force (730 kN)). The units are also equipped with "radial bogies" which offer increased adhesion and better ride quality.[19]

While it retains the basic SD70 designation, the locomotive has several major new features that set it apart from its successful ancestor such as a vibration-isolated powertrain, and alternator start capability. In addition, it features a newly redesigned cab reminiscent of the earlier SD70M, featuring the classic "teardrop" windshields first introduced on the FP45 in December 1967; new fabricated trucks; a longer frame at 76 feet 8 inches (23.37 m); longer radiators with three radiator fans instead of two; an additional step on the front and rear; and a smoother long hood roofline.[20][21][22][23]

Fifteen SD70ACe-T4 demonstrators were built at Muncie, Indiana by November 2016. Union Pacific was the first customer to order SD70ACe-T4's. UP 3012–3014, the first production SD70ACe-T4's, were assigned to active service in early November 2016.

Union Pacific acquired 100 SD70ACe-T4's: 12 former demonstrators rostered as UP 3000–3011, and 88 production units (3012–3099). 3012-3056 were built at Bombardier's Sahagun, Mexico plant. 3057-3099 will be built at Muncie, IN, following completion of the Tier 4 credit SD70ACe's UP 8997–9096. All UP SD70ACe-T4's are classified as SD70AHs.

SD70ACeP4-T4's EMDX 1603 and 1604 were built and painted as demonstrators for the BNSF Railway. These units have a B1-1B wheel arrangement akin to the SD70ACe-P4.

In August 2018, CSX Transportation ordered 10 SD70ACe-T4's. They were classified by CSX as ST70AH. In July 2023, CSX Transportation sidelined their ST70AH locomotives due to the leasing agreement being expired. All 10 have been taken back to PRLX and will more than likely be used as parts or on the lease fleet.

Norfolk Southern originally ordered 10 SD70ACe-T4's, but opted for more SD70ACe Tier-4 credit locomotives instead. The cancelled units are currently part of the Progress Rail lease fleet.

EMDX 1501 will remain in Progress Rail Services ownership as a test bed.

SD70ACe/LCi (2005–present)

[edit]
BHP SD70ACe/LCi No. 4308

The SD70ACe/LCi is a low clearance, export version of the SD70ACe. The LCi in the model designation stands for Low Clearance international as these locomotives are designed to negotiate the tight clearances under the mine equipment. External differences between the SD70ACe and SD70ACe/LCi models include the addition of marker lights, number boards located lower on the nose rather than on top of the cab, windscreen protector panels (to deflect abrasive iron ore when in mid train position), fire suppression canisters, louvre style vents, different horn and subtle differences with handrails.[24][page needed]

In 2004, BHP Billiton ordered 14 SD70ACe/LCi locomotives for use on iron ore trains in the Pilbara region of Western Australia.[25] The first member of the class (4300) was purchased for parts and dismantled upon arrival in Australia. This was because it was cheaper to purchase a complete locomotive than buy the components individually.[26][27] They were named after sidings on the BHP system.[24][page needed][28] Since they did not have the newer, isolated cab of the second and subsequent batches, 4301–4313 were traded in to Progress Rail for locomotives with newer cab assemblies and repatriated to the United States in January 2015 being taken to Muncie, Indiana for store.[29] They were overhauled and sold to Chemin de fer Arnaud (4), Montana Rail Link (4) and Quebec North Shore & Labrador (5).[30]

BHP operated in 2015 a fleet of 23 SD70ACe/LCi locomotives beside of 142 standard SD70ACe, from which the newest locomotives are built in 2014.[31]

The second batch of 10 SD70ACes (4314–4323) arrived between August and November 2006. An order for a third batch of 13 SD70ACe/LCi's (4334–4346) was placed in August 2007, but such was the demand for locomotive power in the Pilbara region, a deal was done with BNSF for BHP Billiton to purchase ten standard North American SD70ACes (4324–4333) that were in build as their 9166, 9167, 9184–9191. Construction was sufficiently advanced when the deal was concluded for them to have been painted, hence they were delivered in BNSF orange livery. Some modifications have been made to bring them in line with the rest of the fleet. A fifth batch of SD70ACes (Numbers 4347–4355) was delivered in July 2009.[24][page needed][26]

An additional 18 units (numbers 4356–4373) were delivered in the second half of 2010, bringing the total of SD70ACe type locomotives in service to 72.[27] In March 2012, BHP Billiton ordered a further 80.[32] As at October 2020, BHP operated 10 SD70ACes (4324–4333) and 174 SD70 Ace/LCis (4314–4323, 4334–4497)[33]

In July 2012 fellow Pilbara operator, Fortescue, took the delivery of the first of a fleet of 19, later extended to 21 (701–721).[27][34][35]

SD70ACS (2009–present)

[edit]
Saudi Railway Company EMDX SD70ACS No. 3025

The SD70ACS is a 4,500 horsepower (3,400 kW) AC variant for heavy haul freight, used in desert environments. The first 25 units were ordered for Saudi Railway Company in April 2009 and assembled in the London, Ontario, plant for delivery in the second half of 2010. Special features include a pulse filtration system, movable sand plows, EM2000 control system and FIRE display system.[36]

Mauritania's Société Nationale Industrielle et Minière placed a contract for six SD70ACS locomotives in October 2010.[37]

In July 2011 Etihad Rail ordered seven SD70ACS locomotives for delivery in 2012.[38] Seven locomotives were delivered in 2013.[39]

SD70ACe-BB (2015–present)

[edit]

In October 2015, EMD started producing SD70ACe-BB locomotives for Brazilian 1,000 mm (3 ft 3+3⁄8 in) railroads.[40] Unlike the standard SD70ACe, the SD70ACe-BB has a B+B-B+B wheel arrangement, meaning that it has eight axles instead of six. To fit the B+B trucks, the SD70ACe-BB was elongated to 74 ft 9 in (22.78 m), making it 2 ft 5 in (0.74 m) longer than the standard SD70ACe.

SD70ACe/45 (2004–present)

[edit]
Eldorado Brasil SD70ACe/45 No. 9558

The SD70ACe/45 is a diesel-electric locomotive built by EMD plant in Sete Lagoas, MG Brazil. Different from the SD70ACe in North America, the SD70ACe/45 has a longer frame (76 ft. 6 in.) and three radiator fans on the radiator section since it uses the same car body of the SD80ACe produced by EMD plant in London, Canada to Vale mining in Brazil. It uses 1,600 mm (5 ft 3 in) gauge. 80 SD70ACe/45s had been built.[41]

SD70IAC (2019–present)

[edit]

In early 2019 with the delivery of the new SD70ACe-T4C locomotives to Norfolk Southern, a new type of the T4C (Tier 4 Credit) locomotives was rolled out of Progress Rail in Muncie, Indiana. IAC stands for Individual Axle Control. They are still classified as SD70ACe's on the side of the locomotive but are designated as SD70IAC within the cab controls. The new IAC system improves the existing traction system.

SD70ACe/LW (2007, 2021–present)

[edit]

The SD70ACe/LW is designed specifically for rail networks using Russian gauge, featuring a new isolated cab similar to the flat nosed cab of the GT46C-ACe Gen-II. The SD70ACe/LW has a 16-710G3C-T2 prime-mover with 4,500 horsepower. It uses an AC traction system with a top speed of 74 mph (120 km/h).[42] Although it was designed in 2007, the first orders only occurred in mid-2021, when 16 were purchased for the Mongolian Tavan Tolgoi-Gashuunsukhait Railway project.[43]

Rebuilds

[edit]

SD70ACU

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Norfolk Southern SD70ACU No. 7305
Canadian Pacific SD70ACU No. 7029
BNSF SD70MACe No. 9753

The SD70ACU is a rebuild performed by Norfolk Southern and Progress Rail Services. It is originally an SD90MAC (or better known as a SD9043MAC) that has been rebuilt to replace its Siemens electrical components with equipment from Mitsubishi and replace the cab with the new EMD Phase-II cab to comply with the most recent safety requirements.[44]

100 of the 110 units Norfolk Southern purchased were originally SD9043MACs previously operated by Union Pacific.[44] The other 10 units were acquired by a trade with Cit Group for MP15DCs.[citation needed] All NS-owned SD9043MACs were rebuilt by NS at its shops in Altoona, Pennsylvania.[citation needed] The first locomotives were released from the shop in January 2016.[44] By May 7, 2019, all 110 SD70ACU units owned by Norfolk Southern were completed and released to active service.[citation needed] 46 of these were sold in November 2020 with 30 of them going to Ferromex in 2024.[citation needed]

Canadian Pacific has also begun a program to convert their SD90MAC units into SD70ACUs, but unlike Norfolk Southern, Progress Rail is performing the rebuilds.[45] The initial order was for 30 units and then increased to 60.[46] Canadian Pacific originally rostered 61 SD90MACs, which spent much of the 2010-decade parked in long-term storage, with the exception of three, which were retired and scrapped in 2012.[citation needed] The remaining 58, along with two surplus Union Pacific SD90MACs, will be used as cores for the 60 SD70ACUs. These units began delivering in 2019.[46]

From this order came numerous heritage units. Namely: CP 7010-7014 in CP's tuscan red, gray, and gold paint scheme with script lettering, CP 7015-7019 in the same paint but with block lettering,[47] CP 7020 in NATO green representing temperate climates, CP 7021 in the sand color used for arid climates, CP 7022 wears the grey, red and black colour pattern of modern warships, CP 7023 wears a two-tone gray paint scheme inspired by fighter jets, CP 6644 wears the camouflage colours applied to Royal Canadian Air Force “Spitfire” fighter planes flown at the Allied invasion of Normandy, France, on June 6, 1944 and is numbered in remembrance of that date.[48][49] CP 7015 led the CP business train for a short time due to a mechanical failure with the regular units and then returned to freight service.[50][51] The remaining units received the standard CP red paint scheme.

In 2021, Canadian Pacific purchased 40 more SD90MACs from the Union Pacific for further rebuilding into SD70ACU engines.[citation needed]

SD70ACC

[edit]

The SD70ACC is the latest rebuild in Norfolk Southern's DC to AC program. It has the new EMD safety cab, similar to the SD70ACe cab, but with the “teardrop windshield”, much like the SD70ACe-T4. The SD70ACC has been rebuilt with AC traction motors, an AAR-style control stand, an electrical cabinet with Mitsubishi electronics, a new main alternator, and additional weight to increase the maximum weight to 432,000 pounds (196.0 t). The SD70ACC is rated at 4,500 horsepower (3,355.649 kilowatts), has a fuel capacity of 4,900 US gallons (19,000 L), and has dynamic braking, cab signals, and LSL (Locomotive Speed Limiter).[citation needed] The first locomotive was released to service in November 2018.[52]

Norfolk Southern is rebuilding its fleet of SD70s into SD70ACC specifications.[53][54] The first two units, 1800 and 1801, were unveiled in a special yellow and grey paint scheme to promote the DC to AC program, similar to the paint schemes used on the first GE AC44C6M. As of 2024, 52 Units have been rebuilt and have since been released to service.[55]

SD70MACe

[edit]

The SD70MACe is a rebuilt SD70MAC locomotive with new Mitsubishi electronics and traction motors to replace the Siemens traction motors. It was first rebuilt for the BNSF Railway,[56] and later rebuilt for CSX (classified as SD70AC) and KCS.

SD70MACH

[edit]
Metra SD70MACH No. 515

The SD70MACH is an SD70MAC rebuilt by Progress Rail for Metra. A purchase of 15 SD70MACHs for passenger service has been approved, with options of up to 27 more.[57] The first unit was delivered in 2022 and entered service in late 2023.[58] They are the first six-axle passenger locomotives since the EMD F40C and the Alaska Railroad's HEP-equipped SD70MACs.

The rebuild includes the addition of head end power (HEP) along with meeting Tier 3 emissions. The axles are configured in a B1-1B configuration as one inverter is repurposed for supplying HEP.[59] The SD70MACH is designed to be significantly quieter than older freight models, generating 85 dBA Of noise during idle and operating which is 40% quieter than the SD70AC and also designed to have a 50% smaller noise footprint compared to the F40PHs.

SD70ICC

[edit]

The SD70ICC is an SD70M-2 rebuilt with AC traction by Progress Rail. Units are rebuilt from Norfolk Southern & PRLX SD70M-2's. Norfolk Southern is currently the only operator of these units.[60]

Operators

[edit]
Railroad Qty. Road numbers Notes
SD70
Illinois Central 40 1000–1039[61] Units 1006, 1013, 1014 & 1023 were wrecked and retired.
Norfolk Southern 80 2501–2580[62] Units 2557–2580 are ex-Conrail units, but built to NS specifications. 52 units have been rebuilt as SD70ACCs, and all remaining units were sold to PRLX in 2020.
Southern Peru Copper Corporation 2 60–61 Assembled in April 1999, these were the last standard or "spartan" cab units produced by EMD, and were built as an add-on to Illinois Central SD70's 1020–1039, even matching their specifications.
SD70M
Norfolk Southern 68 2581–2648 All sold to PRLX in 2020.[62] Units 2596, 2598, 2607, 2608, 2613, 2616, 2620, 2622, 2637, 2645, 2648 sold to RJ Corman in Fall 2022.[63] 5 units sold to Ontario Northland in 2022. Units 2601, 2605, 2611, 2612, 2614, 2621, 2623, 2628, 2635, and 2646 sold to Indiana Rail Road in 2023.
3 2797–2799 Units are ex-New York, Susquehanna & Western 4050, 4052, 4054. Acquired in September 2014, but later sold to PRLX in 2020.
Union Pacific 1,452 1616, 1979, 2001–2002, 3778–3984, 3986–4013, 4015, 4016–4140, 4142–4331, 4333–4391, 4393–4689, 4692–5231 Units 2001-2002 are ex 4690–4691, 3778 is ex 4141, renumbered for SD70ACe 4141, and No. 3985 is occupied by steam locomotive 3985.[64] Unit 4014, along with 4884, was given the honor of escorting UP's 4-8-8-4 Big Boy move to Cheyenne for restoration, and eventual return to the active roster. To avoid confusion, the "Big Boy" was renumbered UPP 4014.[65] The SD70M has since been renumbered as UP 4479, becoming the second UP SD70M to carry that number as the first 4479 was retired after being wrecked. This renumbering allows the Big Boy to be numbered as UP 4014.[66]

• 9 units sold to Lake State Railway • Units 4120-4128 sold to Paducah & Louisville and Evansville Western • Units 4375 and 4672 sold to Herzog • 10 units sold to Tren Interoceanico • 4 units sold to Florida, Gulf and Atlantic Railroad • 3 units sold to Grenada Railroad • 6 units sold to Yadkin Valley Railroad •4 units sold to Lancaster & Chester Railroad

Units 2001 & 2002 were, and still are, painted in tribute of the 2002 Winter Olympics which took place in Salt Lake City, UT.

Units 4545, 4811, and 4929 were all wrecked and retired in 2004.

Unit 4332 renumbered to 1979 in 2021 and wears the We Are One livery

Unit 4015 (first) was a diesel helper for UP 4014, and was renumbered to 1616 to honor the 16th president, Abraham Lincoln, and was released on April 30, 2025.

Unit 4392 was renumbered to 4015 (2nd) to replace the first 4015.

PRLX (Progress Rail Leasing) 25 4675–4699 All units are former CSX and are also former EMDX demonstrators 7000–7024. 4675 and 4677 were sold to CORP in 2022.
71 2581–2648, 2797–2799 They are ex-Norfolk Southern 2581–2648 and 2797–2799 units. Purchased between March and April 2020. 10 units were sold to RJ Corman as of Fall 2022. 10 more units were sold to Indiana Rail Road in 2023.
Ferrominera Orinoco 6 1052–1057 N/A
Carajás Railroad (EFC) - Companhia Vale do Rio Doce 55[67] 701-755 These are wide gauge 1,600 mm (5 ft 3 in) units.
Lake State Railway 9 6430–6438 All are ex-UP units. Acquired in May 2022. Unit 6437 painted in a Pere Marquette-inspired livery.[68]
RJ Corman 10 1973, 2023, 2596, 2598, 2613, 2616, 2620, 2622, 2637, 2645, 2648 All units are former NS. Acquired in Fall 2022.[69] Units 1973, 2023, 2596 & 2620 are painted in 50th anniversary scheme.
Indiana Rail Road 10 7001–7010 All units are former NS. Unit 7001 is in Operation Lifesaver paint. Unit 7010 is in a veterans scheme.
Paducah & Louisville Railway / Evansville Western 9 4120-4128 All units are former UP
Southern Pacific 25 9800-9824 All to Union Pacific. Renumbered 3974-3984, 3986-3999
Ontario Northland Railway 5 2120-2124 Ex-NS 2631, 2642, 2633, 2639, 2644
Tren Interoceánico 10 4378, 4671, 4674, ????, ????, ????, ????, ????, ????, ???? Ex-UP, 7 units unidentified
SD70I
Canadian National 26 5600–5625[61] N/A
SD70MAC
Alaska Railroad 28 4001–4016, 4317–4328[70] The units numbered 4317–4328 have flared radiators for Tier 1 compliance and are equipped with head-end power (HEP) generators for passenger service.
BNSF 786 8800–8989, 9400–9499, 9504–9999[71] Units 9551-9564 sold to PRLX. Unit 8945 sold to KCS. 30 units sold to WFRX. 4 units sold to Red River Valley and Western. 10 units sold to Colorado Pacific Rio Grande Railroad. 7 units sold to Quebec Gatineau Railway. 3 units sold to St. Lawrence & Atlantic Railroad. Unit 9540 sold to Yadkin Valley Railroad. Remaining units in storage. Only used as Yard unit, Backup Multiple Power unit and Distributed Power Unit. Units 8876 and 9724 were wrecked and scrapped. 9400 preserved. 9528 was rebuilt to a snow plow unit and renumbered to 95280.
CSX 220 4500–4589, 4701–4830[72] The 4500s were originally numbered in the 700 series. 4579-4589 are ex-Conrail units. In Storage, units to be rebuilt to SD70MACes. Units 4542, 4716, and 4759 were wrecked and retired, while unit 4500 was retired for parts and eventually scrapped. These are called SD70AC. Unit 4568 is painted in honour of Operation Livesaver's 50th anniversary. Unit 4720 is painted in a "One CSX" initiative scheme that honours the railroad's employees. Unit 4507 was rebuilt into a first responders training prop and renumbered 911343.[73]
Kansas City Southern 75 3900–3902, 3904–3905, 3907, 3910–3916, 3918, 3920–3921, 3924–3926, 3928–3930, 3932, 3934–3935, 3937–3938, 3941–3942, 3944, 3946–3948, 3951, 3953, 3955, 3957, 3961–3964, 3966–3968, 3970, 3972–3974[74] All are ex-Transportación Ferroviaria Mexicana (TFM) units. Some units rebuilt to SD70MACe. Unit 3974 is ex-BNSF 8945. Some units sold to Metra and rebuilt as SD70MACH. 3909 and 3946 sold to Alaska Railroad. 6 units sold to Ontario Northland
PRLX (Progress Rail Leasing) 14 9551-9564 All units are ex-Burlington Northern and later BNSF.
Wells Fargo Leasing (WFRX) 30 8858, 8859, 8861–8868, 8870, 8871, 8877, 8895, 8898–8899, 8901, 8909, 8910, 8912, 8914, 8915, 8959-8966[75] All are ex-BNSF.
Yadkin Valley Railroad 1 9540 Ex-BNSF, BN
SD70ACe
ArcelorMittal, operated by Cartier Railway 5 9001-9005 Delivered in May 2013.
Arkansas & Missouri Railroad 6 70-73, 7001–7002 Units 70-72 are ex-EMDX 1201–1203, and were fitted with mock cab-mounted bells. 73 is ex-KCS 4028. 7001 and 7002 are ex-Tacoma Rail SD70ACe-P4's, and will presumably be renumbered as A&M units 74 and 75.
BNSF 640 8400–8499, 8520–8599, 8749–8799, 8990–9158, 9160–9399[71] 9159 wrecked, rebuilt, and renumbered 8749. 9000 was wrecked and retired in 2021. 9370-9399 are Thundercab units.
20 8500–8519 They are the SD70ACe-P4 model.
Canadian National 4 8100-8103 They are the SD70ACe-P6 model, also set up for Distributed Power operation. Previously in EMDX paint with CN logos, all now repainted. Units are ex-EMDX 1206, 1208–1210.
Canadian Pacific Kansas City 228 3997–4224[74] Units 3997–3999 are ex-EMD demonstrators. 4014 wrecked and was retired. 4028 sold to A&M as 73. In November 2018, 4006 was painted into a veterans scheme.[76] In May 2020, 4009 was painted into a "Salute to Heroes" scheme.[77] units 4014-4015, 4021-4022-4023, 4028, 4031-4032-4033, 4038, 4042, 4046, 4048, 4050 are Retired. KCSM 4084 wrecked and retired. 4200–4224 built in 2015, they are not Tier 4 compliant and are thus restricted to Mexico.
CSX 20 4831–4850 4839 retired due to an alternator failure. All retired in 2017 and sold to Progress Rail (PRLX).
Electro-Motive Diesel Leasing 3 1207, 2012, 4223 1207 is the SD70ACe-P4 model.
Ferromex 97 4000-4096[78] 4000, 4029, and 4063 were wrecked and retired.
34 4100–4133 Built in 2015, these units are not Tier 4 compliant and are thus restricted to Mexico. 4119-4133 are assigned to Ferrosur, and are specially equipped with experimental sheet-metal awnings or "elephant ears" over the radiator air intakes to combat excess heat and enhance engine cooling in the many tunnels through which they must operate.
Luminant (formerly Texas Utitilies Generating Co., TUGX) 2 5308–5309 Units are ex-EMDX 1204 & 1205 respectively.
Montana Rail Link 29 4300–4319, 4400–4408 4316–4319 are ex BHP.[30]
Norfolk Southern 175 1000–1174[62] 1065–1074 and 1080 painted in special historic "heritage" schemes honoring important NS predecessor roads.
Northshore Mining 5 671–675 Ex. Progress Rail CSX units 4832–4833, 4838–4839, 4848.
Quebec North Shore & Labrador 28 501–528 Units 501-507 were built in December 2009; 508-513 were built in August 2011; and 514-523 were built in December 2012.[79] 524-528 are ex BHP.[30]
Tacoma Rail 2 7001–7002 They are the SD70ACe-P4 model and are ex-EMDX 1211 & 1212. Sold to Arkansas and Missouri Railroad in late 2023.[80]
Union Pacific 518 1111, 1982, 1983, 1988, 1989, 1995, 1996, 4141, 8309–8361, 8363-8378, 8380–8382, 8384–8395, 8397–8422, 8424–8823[64] 1111, 4141, 1982, 1983, 1988, 1989, 1995, and 1996 are special painted units. 4141 donated to the Bush Presidential Library in 2019. Units 8315, 8485, 8491, 8542, 8551, 8692, and 8743 were wrecked and retired.
281 1943, 8824–9025, 9027–9104 These units have 8,000 lbs. of extra ballast for more tractive-effort and are classified by Union Pacific as SD70AH. Unit 9026 was renumbered 1943 "Spirit of the Union Pacific" in 2017. 1943, 8997–9025, and 9027–9104 are Tier 4 credit units.
PRLX (Progress Rail Leasing) 14 4831-4850 All units are former CSX. 5 of 19 units sold to Northshore Mining.
10 4324–4333 Originally intended for BNSF and purchased by BHP Billiton when on the production line.[27]
BHP
Fortescue 10 722–732 These are Tier 3 units.
Demonstrator manufactured in Brazil 3 7044–7046 These are wide gauge 1,600 mm (5 ft 3 in)) units.
SD70M-2
Canadian National 190 8000–8024, 8800–8964 All units are equipped for Distributed Power operation. 8952 became CNs GTW heritage Unit[61]
CaterParrott Railnet 2 9000-9001 Former NS
CIT Group 3 140–142[81] All are ex-EMD demonstrators.
Florida East Coast Railway 8 100–107[82] All eight units were returned to lessor in early 2015. Former FEC 100 & 102 now Providence & Worcester Railroad 4301 & 4302, respectively. Former FEC 101 & 103 now Vermont Railway 431 & 432, respectively. Remaining units sold to Florida Gulf & Atlantic Railroad.
Florida Gulf & Atlantic Railroad 4 104-107 All are former Florida East Coast units.
New Brunswick Southern Railway 18 6401–6418 All are former Norfolk Southern units, rebuilt with nose headlights.
New York, Susquehanna and Western Railway 4 4060, 4062, 4064, 4066 All are former Norfolk Southern units.
Norfolk Southern 130 2649-2778 4 units sold to NYSW, 18 units sold to NBSR and rebuilt with nose headlights, 2 units sold to CaterParrott Railnet. Remaining units stored as of 2020. 46 units have been reactivated with units 2674 and 2686 being rebuilt to SD70ICCs 1250–1251 in 2023.[62]
Providence & Worcester Railroad 2 4301-4302 All are Former Florida East Coast units.
Vermont Railway 2 431–432 All are Former Florida East Coast units.
SD70ACe-T4
CSX 10 8900–8909 Delivered July 2019. Leased and later returned to PRLX in 2023.
Electro-Motive Diesel Leasing 1 1501 N/A
Union Pacific 100 3000–3099 N/A
PRLX (Progress Rail Leasing) 65 7201–7252, 8900–8909 10 units part of a cancelled NS SD70ACe-T4 order intended for delivery late 2019. Units 8900-8909 formerly leased to CSX.
SD70ACe/LCi
BHP 184 4300–4323, 4334–4497[27] First 13 repatriated to the United States and sold to Chemin de fer Arnaud (4), Montana Rail Link (4) and Quebec North Shore & Labrador (5), and rebuilt to U.S. specs.[30]
Fortescue 21 701–721[35] N/A
SD70ACS
Etihad Railway 7 TBA Delivered 2013.
38 Ordered Feb. 2020.
Compagnie des Bauxites de Guinée 10 Ordered 10 units.
Mauritania Railway 6 Ordered 6 units.
Saudi Railway Company 25 N/A
SD70ACe-BB
Valor da Logística Integrada 77 8332–8393, 8429-8443 They operate on the lines of Ferrovia Centro-Atlântica. An additional 16 locomotives should be delivered in the first half of 2017.[83]
Demonstrator manufactured in Brazil 2 8795–8796 N/A
SD70ACe/45
América Latina Logística, now Rumo Logística 7[67] 618–624 N/A
Eldorado Brasil 21[67] 9553–9573 Operated by América Latina Logística.
Valor da Logística Integrada 52 6514-6527, 8169-8175, 8255-8265, 8653-8664, Operate on the lines of Ferrovia Centro-Atlântica and Ferrovia Norte-Sul.
MRS Logística 4 618, 7044, 7046-7047 N/A
SD70IAC
Norfolk Southern 50 1175–1234[84] These are SD70ACe/SD70IAC units. SD70IAC units are SD70ACe T4C units with IAC="Individual Axle Control" and are called SD70IAC by NS. All have now been delivered. 1224–1234 delivered in 2022.
SD70ACe/LW
No data currently - - -
SD70ACU
Canadian Pacific 60 6644, 7000–7023, 7025-7059 Rebuilt from CP's SD9043MACs that were in long-term storage, plus additional locomotives bought from Union Pacific. 7010–7019 are outfitted in retro liveries and 7020–7023 and 6644 are armed forces painted units; 6644 is painted as a tribute to D-Day. 7005 and 7011 wrecked in April 2023 and retired.
Norfolk Southern 110 7229–7313, 7315-7339 Rebuilt from ex-UP and ex-CIT SD90MACs.[84] 66 units sold to PRLX, 30 of the PRLX units sold to Ferromex in 2024. 7314 was renumbered to 7339 in 2018.
Ferromex 3 4164-4155-4158 Ex PRLX/NS 7324.7251.7259
SD70ACC
Norfolk Southern 52 1800–1851 Rebuilt from ex-NS SD70s. 1832 wrecked in June 2020 when it hit a tractor trailer then derailed. Later returned to service without its nose painted.
SD70MACe
CSX 220 4500–4589, 4701–4830[72] Rebuilt from SD70MAC units
Kansas City Southern 75 3900–3902, 3904–3905, 3910–3916, 3918, 3920–3921, 3924–3926, 3928–3930, 3932, 3934–3935, 3937–3938, 3941–3942, 3944, 3946–3948, 3951, 3953, 3955, 3957, 3961–3964, 3966–3968, 3970, 3972–3974[74] All are ex-Transportación Ferroviaria Mexicana (TFM) units.
SD70MACH
Metra 15 500 Series There are options for 27 more. Former KCS SD70MAC freight units rebuilt by Progress Rail Services. First unit arrived October 2022, and the first locomotives began running in late 2023.
SD70ICC
Norfolk Southern 2 1250-1251 These locomotives were rebuilt from PRLX/NS SD70M-2 locomotives, numbered 2674 and 2686. They were rebuilt in late 2023 by Progress Rail.

Preservation

[edit]

SD70MAC

[edit]
  • Burlington Northern No. 9400 (the first AC Traction diesel, later BNSF #9400) was donated to the Illinois Railway Museum in June of 2025 and arrived on July 31. The museum plans to repaint her back to the Burlington Northern Executive Green Livery.

[85][86]

SD70ACe

[edit]
[edit]

Footnotes

[edit]

References

[edit]

Further reading

[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

EMD SD70 series

View on Grokipedia
from Grokipedia
The EMD SD70 series is a family of six-axle, medium-horsepower diesel-electric locomotives manufactured by (EMD), a division of , and later by , introduced in 1992 as a direct evolution and upgrade to the earlier SD60 series. These locomotives are powered by EMD's robust 16-cylinder 710G3B prime mover, initially rated at 4,000 horsepower, with later variants uprated to 4,300 or 4,500 horsepower to meet demanding heavy-haul freight requirements. Designed primarily for North American railroads, the series emphasizes reliability, fuel efficiency, and high , featuring options for both DC and AC traction systems across its models. The inaugural model, the SD70, entered production in late 1992 with a standard wide-nose safety cab and DC traction, competing directly against General Electric's Dash 9 series in the market for versatile road freight power. Key variants soon followed, including the SD70M (a cowl-unit version for commuter and freight service, with major orders from Union Pacific, , and Metrolink) and the SD70MAC (an AC-traction model optimized for coal and unit trains). Production of the base SD70 totaled 122 units, mostly for Norfolk Southern and , while the series as a whole expanded to over 5,700 units produced, including international adaptations like the SD70ACe (introduced in 2005 for global heavy-haul applications with AC traction and microprocessor controls) and specialized models such as the SD70ACe-T4 compliant with U.S. EPA Tier 4 emissions standards. Spanning over three decades, the SD70 series represents EMD's longest continuously produced line, with nine major domestic new-build models and numerous export and rebuilt versions, enabling adaptations for diverse gauges, emissions regulations, and operational needs worldwide. Its enduring success stems from the proven durability of the 710 engine—over 12,000 of which power globally—and innovations like the EM2000 for enhanced diagnostics and efficiency. Today, SD70 variants remain in active service across Class I railroads, short lines, and international operators, underscoring their role in modern railroading.

Introduction and development

Overview

The EMD SD70 series is a family of six-axle, 4,000 horsepower (later uprated to 4,300 or 4,500 horsepower in some variants) diesel-electric locomotives produced by (EMD), serving as the successor to the SD60 series and introduced in 1992. Designed for heavy-haul freight service, the series incorporates key innovations such as the 16-cylinder 710G3B engine. By 2025, production across all variants has exceeded 5,700 units, reflecting the model's enduring popularity and adaptability in the rail industry. These locomotives find primary application in North American freight railroading, where their reliability supports operations on , intermodal, and bulk commodity trains. Within the series, designs evolved from DC traction systems in initial models to AC traction in subsequent variants, enhancing and overall efficiency for demanding tasks.

Historical background

In the early 1990s, (EMD) initiated development of the SD70 series to counter General Electric's Dash 9-44CW , which offered 4,400 horsepower and addressed the growing demand for more powerful units capable of handling heavier freight loads amid railroad industry consolidation. This competitive pressure was amplified by the post-merger era, particularly following the 1996 Southern Pacific-Union Pacific merger, which created vast networks requiring enhanced performance for unit trains and intermodal services. The SD70's 4,000 hp rating became a standard benchmark across variants, reflecting EMD's focus on balancing power output with reliability in this evolving market. The series marked a key transition from the SD60 lineup, uprating the 16-cylinder 710-series engine from 3,800 hp to 4,000 hp while incorporating the advanced for precise fuel management, diagnostics, and traction optimization. Introduced as the successor to the "60-series" in , the SD70 emphasized improved electrical systems and self-steering trucks to reduce wheel wear on high-curvature routes. Regulatory considerations also shaped early designs; prototype engines tested in 1991 achieved emission levels of 6 to 7 g/bhp-hr, anticipating the U.S. Environmental Protection Agency's forthcoming locomotive standards that would tighten controls on particulate matter and oxides of . The SD70 prototype underwent initial testing and received certification in 1991-1992, validating its design for high-adhesion freight service. Production milestones followed swiftly, with the first units rolling out in late 1992 and initial deliveries commencing in 1993 to major carriers including Canadian National and , which deployed them on heavy-haul freight routes. These early locomotives set the stage for the series' widespread adoption, influencing subsequent EMD innovations in integration and emissions compliance.

Design features

Engine and electrical systems

The EMD SD70 series primarily employs the 16-710G3C as its prime mover, a V16 configuration with a bore of 9.06 inches and stroke of 11 inches, delivering a total displacement of approximately 186 liters across its cylinders. This engine produces a rated output of 4,300 horsepower at 904 rpm in later variants, an increase from the initial 4,000 horsepower of the 16-710G3B used in early SD70 models, enabling enhanced freight hauling capabilities. Fuel efficiency in the 710 series engines is optimized through uniflow scavenging and electronic fuel injection, achieving approximately 200 gallons per hour at full load for a 4,000-horsepower output, which represents a 5-10% improvement over the preceding series due to reduced specific fuel consumption rates of about 0.35-0.40 pounds per horsepower-hour. These metrics contribute to lower operational costs in heavy-haul service, with the engine's design emphasizing durability for maintenance intervals up to 184 days. The electrical systems in the SD70 series evolved from DC to AC traction configurations to improve performance in demanding freight applications. Early models like the SD70 and SD70M feature DC traction motors, such as the D90TR series, which provide reliable power transmission but are limited by brush wear and lower low-speed torque compared to AC alternatives. Later variants, including the SD70MAC and SD70ACe, incorporate AC traction motors like the EMD AC4800, offering superior adhesion (up to 40% coefficient) and torque curves that maintain high tractive effort at starting speeds below 10 mph without overheating risks associated with DC systems. This shift enhances overall efficiency by reducing wheel slip and enabling sustained low-speed pulling power. Cooling systems in the SD70 series utilize a high-capacity water circuit with approximately 250 gallons of , circulated through radiators and an aftercooler to manage the engine's output, often featuring flared intakes in later builds for improved . Exhaust systems incorporate , with the 16-710G3C employing a single-stage turbocharger in base models and progressing to two-stage setups in advanced versions, where a high-pressure primary turbo boosts low-to-mid RPM performance while secondary units handle higher loads for better combustion efficiency. Power generation for traction is handled by the main , such as the AR20 series in DC-equipped locomotives or the TA17/CA7A in AC models, which converts mechanical energy from into electrical power at up to 4,300 horsepower for the traction . Basic performance estimation uses the relation for continuous (TE in pounds), approximated as: TE=HP×375vTE = \frac{HP \times 375}{v} where HPHP is horsepower and vv is speed in mph, illustrating how power translates to pulling force at varying speeds.

Cab and safety enhancements

The EMD SD70 series introduced significant advancements in cab design, particularly with the adoption of the wide-nose "safety cab" on models such as the SD70M, which enhanced to comply with (AAR) Standard S-580 and (FRA) requirements under 49 CFR Part 229, Subpart D. This design featured reinforced collision posts, anti-climbing mechanisms, and a broader front structure to better protect crew during collisions, marking a shift from earlier narrow-nose configurations in response to industry safety mandates effective from 1990. The safety cab provided improved , including better visibility through larger windshields and padded interiors to reduce injury risk in impacts. Control systems in the SD70 series utilized the EM2000 microprocessor-based platform, which managed throttle response, , and for enhanced operational precision and reliability. Integrated with the , this allowed for real-time monitoring and fault detection, minimizing downtime through alerts. The EM2000's 32-bit processing supported seamless interaction with auxiliary systems, contributing to smoother handling in heavy-haul applications. Standard dimensions for SD70 series locomotives included an overall length of approximately 72 feet 4 inches and a weight range of 384,000 to 432,000 pounds, varying by model configuration and load. These specifications accommodated the safety cab while maintaining compatibility with North American rail infrastructure. Additional safety enhancements encompassed mandatory event recorders to log operational data for accident investigations, vigilant alerters to prevent crew incapacitation, and later integrations for (PTC) compatibility on models produced after 2010 to enable automated speed enforcement and collision avoidance. PTC adaptations involved onboard interfaces and antennas, ensuring compliance with FRA mandates for high-risk corridors by the mid-2010s.

Production variants

SD70

The EMD SD70 is the foundational model of the SD70 series, a six-axle, DC-powered diesel-electric locomotive developed by (EMD) as a direct response to General Electric's Dash 9-44CW. Introduced in late 1992, it represented an evolution of the earlier SD60, incorporating an uprated 16-cylinder 710-series prime mover for enhanced reliability and performance in heavy-haul freight applications. Production of the standard-cab SD70 spanned from 1992 to 1999, resulting in 1,282 units built exclusively for North American operators, with major orders from Canadian National (100 units), Norfolk Southern (103 units), Illinois Central (25 units), and (24 units). Key features of the SD70 include direct-current (DC) traction motors and a standard cab design, delivering an initial rating of 4,000 horsepower from the EMD 16-710G3B diesel engine. Later production examples, starting around 1995, received an upgrade to 4,300 horsepower through refinements in engine tuning and cooling systems, improving fuel efficiency and tractive effort for demanding operations. A distinguishing characteristic is the high short hood forward of the cab, which enhances crew visibility during switching and forward movements compared to lower-hood predecessors. The locomotive's overall length measures 72 feet 4 inches, with a weight of approximately 394,000 pounds, optimized for stability on mainline tracks. The SD70 was primarily deployed in yard service for hump-yard operations and drag freight duties on low-speed, heavy-tonnage routes, where its robust DC drive system provided reliable low-speed control and starting of up to 175,500 pounds. It shares the same 16-710G3B platform with later SD70 variants, facilitating parts commonality across the series. By 2025, a significant portion of the original SD70 fleet has entered retirement due to age and emissions regulations, with many units rebuilt into AC-traction configurations such as the SD70ACC to extend . As of November 2025, retirements have accelerated, with Norfolk Southern retiring over 50 early units amid fleet modernization.

SD70M

The EMD SD70M is a DC-powered variant of the SD70 series, distinguished by its wide-body cab and adaptations for and mixed freight- service. Produced from 1992 to 2007, a total of 1,609 units were built, making it the most numerous model in the SD70 family. The design emphasized crew comfort with a full-width cab that provided better visibility and compared to standard-cab locomotives, while maintaining the core 4,000 horsepower 16-710G3B and DC electrical transmission system common to early SD70 models. A defining feature of the SD70M is its integrated 500 kW (HEP) generator, which supplies electricity to passenger for lighting, , and other onboard systems. To accommodate this equipment, the features a longer frame—measuring 73 feet 2 inches overall—extending the carbody beyond the standard SD70 configuration. This setup enabled the SD70M to serve in both heavy freight duties and commuter operations, where reliable power for trailing was essential. The majority of SD70M production went to , which ordered 1,414 units primarily for freight service across its extensive network, though the HEP capability supported occasional passenger assignments. Other operators, including commuter railroads such as Metrolink in and in , incorporated SD70Ms into their fleets for mixed-service roles, leveraging the locomotive's versatility in regional passenger and light freight tasks. By 2025, the SD70M's age—approaching or exceeding 30 years for most units—has led to widespread retirement or rebuilding programs, particularly among Class I railroads seeking compliance with updated emissions standards and improved efficiency through newer variants like the SD70ACe. As of November 2025, Union Pacific has retired over 200 units, with many repurposed for short-line service or rebuilt. Many surviving examples have been upgraded with modern components or repurposed for short-line service, marking the end of their frontline era.

SD70I

The SD70I is a specialized variant of the EMD SD70 series, developed for freight service in and featuring enhancements tailored to the operational demands of the Canadian National Railway (). Built exclusively for , this model incorporates an isolated cab design, known as the "Whisper Cab," which uses rubber gaskets to separate the cab from the locomotive frame, thereby reducing noise and vibration transmission to the crew compartment. This isolation extends to the engine compartment as well, further minimizing disturbances during operation. Like the base SD70, the SD70I employs DC traction motors for propulsion, powered by the standard 16-cylinder EMD 710G3A rated at 4,000 horsepower. Production of the SD70I totaled 26 units, all delivered to between July and November 1995, with road numbers 5600 through 5625 and builder's numbers 946523-1 through 946523-26. These locomotives were constructed at EMD's LaGrange, facility to meet the needs of CN's extensive freight network across Canada's diverse terrain and . The design prioritized durability for heavy-haul applications, with the isolated compartments providing a more comfortable working environment in prolonged service. As of 2025, all 26 SD70I units remain in active service with , reflecting a low retirement rate and the model's proven reliability in demanding conditions. Recent observations confirm their continued use in mainline freight operations, underscoring their nearly three decades after introduction.

SD70MAC

The SD70MAC was the first (AC)-powered variant in the EMD SD70 series, introduced in as a response to the growing demand for locomotives with superior in heavy-haul applications. Developed following prototypes based on the earlier SD60MAC, it represented EMD's production entry into wide-scale AC traction technology, offering improved adhesion and efficiency over (DC) predecessors. The model shared the series' 16-cylinder EMD 710G3B prime mover, rated at 4,000 horsepower. Production of the SD70MAC spanned from to , with 1,109 units built, making it one of the most numerous variants in the series and a staple for unit and heavy freight trains. Major customers included the Burlington Northern Santa Fe (BNSF), which deployed large fleets for service in the , leveraging the locomotive's robust design for operations. Key features included AC traction motors that enhanced starting , delivering a starting of 175,500 pounds at 33% , along with a transverse spanning the underframe for improved and capacity of up to 5,500 gallons. The SD70MAC's design innovations, such as its isolated cab and radial steering (HTES), contributed to better ride quality and reduced in high-mileage heavy-haul environments. Internally at EMD, the DC-powered SD70 was referred to as the "Mother" and the AC-powered SD70MAC as the "Child," reflecting the evolutionary relationship between the models. The sandbox placement on the sideframes optimized sand delivery while aiding overall across the six axles. By 2025, many SD70MAC units had undergone extensive rebuilds to extend their service life, including conversions by for commuter applications on railroads like and comprehensive overhauls by CSX to upgrade components and improve efficiency. These efforts underscore the model's enduring legacy in North American railroading, with rebuilt examples continuing in both freight and passenger roles. As of November 2025, BNSF continues to use rebuilt SD70MACs in coal service, with no major retirements reported this year.

SD70ACe

The EMD SD70ACe is a six-axle, AC-traction diesel-electric freight locomotive developed by (EMD) as the flagship wide-cab model in the SD70 series, debuting in 2005 as an evolution from the SD70MAC with refinements for emissions compliance and crew ergonomics. It integrates the proven 16-cylinder EMD 710G3C-T2 prime mover, delivering 4,300 horsepower for heavy-haul applications, paired with an AC traction system that enhances , , and overall reliability in demanding service. The design emphasizes operational efficiency, with the engine tuned for optimized fuel consumption through advanced combustion management, achieving up to 6% better efficiency than comparable predecessors in field tests. Key features include a wide safety cab with improved , ergonomic controls via the EM2000 system, and a robust frame supporting up to 432,000 pounds, enabling versatile use in intermodal, , and manifest trains. The AC offers continuous of 155,000 pounds and starting effort up to 200,000 pounds, making it ideal for steep grades and high-tonnage operations. Fuel capacity stands at 4,900 gallons, supporting extended runs while the lean-burn characteristics of the 710 reduce lifecycle use by an estimated 250,000 gallons per unit compared to Tier 0/1 models. Production of the base SD70ACe ran from 2005 to 2015, with 1,946 units constructed primarily for North American Class I railroads, including (660 units), (788 units), and (245 units). Early Phase 1 models (2005–2014) featured standard radiator sizing, while Phase 2 units introduced from 2015 incorporate body refinements such as a larger section for enhanced cooling and in high-load environments. The model has seen international adoption, with exports to operators like in adding 116 units to support cross-border freight. As of 2025, the SD70ACe continues in active service across fleets, reflecting its enduring reliability and adaptability, with approximately 1,200 units still operational in various configurations, including rebuilds. This sustained use underscores its role as a benchmark for modern heavy-haul locomotives, balancing power, , and in an evolving rail industry. As of November 2025, BNSF has initiated a rebuild program for 100 early units to Tier 3 compliance.

SD70M-2

The SD70M-2 is a DC-traction variant of the EMD SD70 series, introduced as a redesign to comply with the U.S. Environmental Protection Agency's Tier 2 emissions standards that took effect in 2005. It builds on the SD70M platform by incorporating updated electronic controls and engine modifications for reduced emissions, while retaining the six-axle configuration and wide-nose cab for enhanced crew visibility and comfort. Production of the SD70M-2 spanned from 2005 to 2011, with a total of 331 units built at EMD's facilities in , and . These locomotives were ordered primarily by freight carriers, including 171 units for (numbered 8800–8899 and additional), 75 units for , 30 units for (8800–8829), 20 units for (1800–1819), and 10 units for CIT Rail (100–109), among others. Key features of the SD70M-2 include a 4,300 horsepower 16-cylinder EMD 710G3C-T2 prime mover, DC traction motors providing 163,000 pounds of starting , and the EP2000 microprocessor-based for optimized throttle response and diagnostics. The design emphasizes lower emissions through advanced turbocharging and aftertreatment systems, achieving significant reductions in nitrogen oxides and particulate matter compared to earlier SD70M models. While primarily intended for freight service, the wide cab design offers improved suitable for extended operations, including potential urban or mixed-use applications. As of 2025, the SD70M-2 remains in active service across North American fleets, particularly with Norfolk Southern and Canadian National, where units continue to handle heavy-haul freight duties. Due to their relatively recent and compliance with modern standards, fewer SD70M-2 locomotives have undergone major rebuilds compared to older variants in the series. As of November 2025, all units are active with no reported retirements.

SD70ACe-T4

The SD70ACe-T4 is a six-axle AC-traction diesel-electric developed by (EMD) to comply with the U.S. Agency's (EPA) Tier 4 Final emissions standards, which took effect for locomotives on January 1, 2015. It represents an evolution of the SD70ACe platform, retaining the wide-nose cab and overall body design while incorporating a new four-stroke prime mover to achieve significant emissions reductions without relying on aftertreatment systems like (SCR). Production began in 2015, with the model debuting at the Railway Interchange exhibition that year. The locomotive is powered by EMD's 12-1010J four-stroke , a 12-cylinder unit rated at 4,400 horsepower (3,300 kW), which replaced the two-stroke 16-710 series used in prior SD70 variants. This engine design enables compliance with Tier 4 standards by reducing nitrogen oxides () emissions by over 80 percent and particulate matter by 70 percent compared to Tier 3 levels, primarily through advanced combustion and techniques rather than urea-based additives. The SD70ACe-T4 maintains similar performance metrics to its predecessor, including a starting of 200,000 lbf (890 kN) and continuous of 175,000 lbf (780 kN), while supporting up to 108,000 lbf (480 kN). By November 2025, approximately 179 units of the SD70ACe-T4 had been produced, with major orders placed by Union Pacific Railroad (UP) and BNSF Railway. UP classified its units as SD70AH, numbering them from 3000 to 3099 (100 units) and assigning many to heavy-haul coal service, while BNSF operates a fleet of 65 units for similar freight applications. Smaller orders went to operators like CSX Transportation, which acquired 10 units in 2019 for phosphate transport, and two demonstrators. The model offers quieter cab operation due to the four-stroke engine's lower vibration and noise profile, enhancing crew comfort during long-haul runs. However, early units faced challenges including higher maintenance costs from the novel engine design and reported reliability issues, such as increased fuel consumption and enroute failures, which limited broader adoption. As of November 2025, UP has addressed some issues through software updates, with the fleet operating reliably in coal service.

SD70ACe/LCi

The SD70ACe/LCi is a low-clearance variant of the SD70ACe, designed specifically for heavy-haul operations in regions with restricted vertical profiles and high ambient temperatures. It incorporates the wide cab configuration of the base SD70ACe model for improved crew comfort and visibility. Powered by a turbocharged 16-cylinder EMD 710G3C-T2 prime mover rated at 4,300 horsepower, the employs AC traction motors for efficient power delivery to its six axles, enabling robust performance in demanding freight service. Key to its adaptability are emissions control features, including a liquid-cooled (EGR) system that ensures compliance with EPA Tier 2 and Tier 3 standards, as well as equivalent international regulations for non-U.S. markets. The cooling system has been specifically optimized with enhanced radiators and airflow management to maintain performance in extreme hot climates, such as those encountered in arid mining districts. This variant's EM2000 further enhances and reliability, supporting extended maintenance intervals of up to 184 days between overhauls. Production of the SD70ACe/LCi commenced in 2005 and remains ongoing as of 2025, with approximately 150 units delivered primarily to Australian iron ore operators for use in the region. Notable deployments include fleets for , where over 100 low-clearance units haul massive ore trains, demonstrating the model's suitability for high-tonnage mining rail networks. Additional units have served export markets in and , tailored to local and environmental requirements. In 2025, continues assembly of related SD70ACe variants at its Sete Lagoas facility in , supporting ongoing demand from South American heavy-haul operators. As of November 2025, 's fleet operates without major issues, contributing to record ore exports.

SD70ACS

The SD70ACS is an export variant of the SD70 series, derived from the SD70ACe and optimized for heavy-haul freight operations in harsh environmental conditions. It features AC traction and the prime mover, delivering 4,300 horsepower for demanding applications. The incorporates the EM2000 for enhanced reliability and an isolated cab for crew comfort. Production of the SD70ACS began in 2009, with the initial order of 25 units for the Saudi Railway Company to support freight services in desert regions. Additional units have been supplied to operators in the (30 units for ) and (19 units for SNIM), bringing the total to over 80 in service by 2025. These locomotives are designed with robust cooling systems and dust filtration to withstand high temperatures and abrasive conditions. The model stands out in the SD70 series for its adaptations to extreme climates, including Tier 3 emissions compliance and a top speed of approximately 112 km/h. All units remain active as of 2025, contributing to regional freight networks where they provide efficient power for and . As of November 2025, Saudi Arabia's fleet has been expanded with maintenance upgrades for extended life.

SD70ACe-BB

The SD70ACe-BB is a meter-gauge variant of the EMD SD70ACe diesel-electric , specifically engineered for Brazilian rail networks with infrastructure constraints such as limited capacities. It employs an eight-axle (B-B-B-B) rather than the standard six-axle C-C configuration, distributing the locomotive's weight across more axles to comply with limits typically around 24.5 metric tons while maintaining high for heavy freight . This model incorporates the same proven as the standard SD70ACe, featuring a 16-cylinder EMD 710G3B-T2 rated at 4,300 horsepower and AC traction motors for efficient power delivery. The design prioritizes reliability in challenging environments, including a microprocessor-controlled EM2000 system for optimized performance and , along with an isolated cab for crew comfort. It achieves a maximum speed of 80 km/h (50 mph) and delivers starting of approximately 724 kN, enabling it to handle demanding loads on curves up to 45 meters radius. Production of the SD70ACe-BB commenced in at EMD's facility in Sete Lagoas, , , tailored for narrow-gauge operations on lighter rail infrastructure. The locomotives are primarily deployed by VLI Logística, a major Brazilian freight operator partially affiliated with Vale, for transporting commodities including along the Southeast corridor of the Ferrogrão Centro-Atlântica railway, where axle load restrictions necessitate the multi-axle setup to maximize payload without exceeding track limits. Initial deliveries included 5 units in , with additional batches following. As of 2025, production remains limited and concentrated in , with VLI placing an order for eight additional units in 2024 as part of a broader 20-locomotive agreement to expand its fleet for enhanced cargo capacity on meter-gauge lines, delivered by November 2025. This ongoing focus underscores the variant's role in modernizing Brazilian rail freight for resource-intensive sectors like , where the eight-axle design allows greater hauling power compared to traditional four-axle locomotives while adhering to regional standards. Total built: approximately 30 units.

SD70ACe/45

The SD70ACe/45 is a specialized variant of the EMD SD70ACe , engineered for heavy-haul freight operations with an uprated power rating of 4,500 horsepower to meet the demands of high-tonnage trains. It employs the 16-710G3C-T2 , a turbocharged 16-cylinder prime mover that delivers enhanced performance over the standard model's 4,300 horsepower output, while maintaining the AC traction system for improved and on steep grades and heavy loads. This configuration allows for greater starting , typically around 600 kN, making it suitable for arrangements in long consists. Production of the SD70ACe/45 commenced in 2004 and has continued intermittently to the present day, with approximately 50 units built exclusively for Australian operators, including , to support the nation's extensive export network. These locomotives are tailored for the rigorous conditions of Queensland's long-haul routes, where they haul unit trains from inland mines to coastal ports over distances exceeding 1,000 kilometers; key adaptations include extended-range fuel tanks with capacities up to 10,000 liters to minimize downtime during remote operations. The design incorporates robust cooling systems and dust filtration to withstand the dusty, high-temperature environments of open-cut regions. As of 2025, the SD70ACe/45 fleet remains fully active in revenue service, primarily with on lines, and has undergone minor retrofits for enhanced , such as optimized and auxiliary systems compliant with evolving Tier 3 emissions standards. Ongoing focuses on extending component life in high-cycle operations, ensuring continued reliability for Australia's vital export commodity transport. As of November 2025, announced plans for hybrid conversions of 10 units to reduce emissions.

SD70IAC

The SD70IAC is a specialized variant of the EMD SD70 series with a fully isolated cab to significantly reduce noise and vibration levels for crew comfort, drawing from designs like the SD70I but updated for modern standards. Introduced in 2018, it features AC traction as standard and is powered by the series engine tuned to 4,500 horsepower for mainline freight efficiency. The isolated cab minimizes transmission of engine vibrations and noise, beneficial for extended operations. Production of the SD70IAC totaled 60 units from November 2018 to November 2019, all for (road numbers 1175–1234) for heavy freight service across their network. Units 1225–1234 were originally built as demonstrators and acquired by NS in 2022. These locomotives are deployed in general freight, including intermodal and coal trains, where the quiet cab enhances crew . The model complies with EPA Tier 3 standards through optimized engine controls. As of 2025, all 60 SD70IAC units are in active service with Norfolk Southern, with two (1230 and 1231) painted in special schemes released in November 2025. The variant supports NS's fleet modernization, with low reported and potential for emissions upgrades. Seven units are in storage for routine checks as of November 2025.

SD70ACe/LW

The SD70ACe/LW is a specialized of the EMD SD70ACe diesel-electric , engineered for rail networks with stringent weight limits, particularly on bridges and tunnels in European and Asian infrastructure. Introduced to address load restrictions on 1,520 mm gauge lines, it maintains the core AC traction system and 4,300 horsepower output of the standard model while prioritizing reduced mass for operational compatibility in sensitive environments. Production commenced in 2007 for initial exports to Russian markets, with renewed manufacturing from 2021 onward focused on Asian applications, resulting in approximately 30 units tailored for light-rail freight service. Key features include a nominal weight of 150 metric tons (approximately 331,000 pounds), achieved through construction that lowers the maximum to 25 metric tons, enabling safe passage over restricted structures without compromising or reliability. Powered by the proven 16-710G3C-T2 turbocharged , the integrates EM2000 controls for efficient heavy-haul performance on routes where standard models exceed tolerances. This design supports broad-gauge operations in regions with aging or capacity-constrained viaducts and tunnels, enhancing freight capacity without requiring costly upgrades. Exports have primarily targeted Eurasian operators, with units delivered to in the initial 2007 batch for testing and deployment on weight-limited corridors. Subsequent production emphasized Asian markets, exemplified by a 2021 order for 16 locomotives to support Mongolia's Tavan Tolgoi-Gashuunsukhait line, where the lightweight configuration facilitates higher train frequencies on the 234 km heavy-haul route. In 2025, completed delivery of the 16-unit order to Bodi International for Mongolia's Gobi railway operations, bolstering the network's ability to transport exports amid growing demand; these units entered in October 2025, operating alongside compatible broad-gauge equipment to optimize throughput on with axle load caps. As of November 2025, all units are active with positive performance reports in cold climates.

2TE3250

The 2TE3250 is a twin-unit diesel-electric freight developed by as an export variant of the EMD SD70ACe platform, specifically tailored for heavy-haul operations on (RZD). It consists of two permanently coupled SD70ACe power units sharing a common , delivering a combined output of 8,600 hp from 16-cylinder engines. Designed for demanding Siberian routes, the locomotive employs AC traction motors to enhance efficiency and traction in heavy freight service. Key adaptations include reconfiguration for the 1,520 mm broad gauge track standard in Russia, along with cold-weather hardening features such as engine block heaters and cab air intake heaters to ensure reliable performance in extreme sub-zero temperatures. The units incorporate the EM2000 microprocessor-based digital control system for optimized operation, monitoring, and diagnostics. With a Co'Co' + Co'Co' wheel arrangement, the design prioritizes durability and power density for long-haul coal and mineral transport in remote regions. Production of the 2TE3250 began in at Progress Rail's facility in , with the first twin-unit (designated 2TE3250-001/002) shipped in February and delivered to Yakutia Railway—a of RZD—for testing in . This prototype underwent trials on the Baikal-Amur Mainline and other non-electrified sections to evaluate its suitability for harsh Arctic conditions. Initial plans called for potential joint production at Yakutia's Aldan depot if tests succeeded, but by 2022, negotiations stalled over pricing, limiting deliveries to the single test unit. As of November 2025, the prototype remains in testing with no further production announced.

Rebuild variants

SD70ACU

The SD70ACU represents a key component of Norfolk Southern's locomotive rebuild initiative, undertaken in collaboration with , a subsidiary that owns (EMD). This program transforms former SD90MAC locomotives—originally built with AC traction—into updated SD70-class units by overhauling major systems, including the replacement of the original widenose cab and electronics with modern EMD SD70ACe-style components such as a standard cab compliant with (FRA) crashworthiness standards, revised electrical cabinets, and enhanced control systems. The resulting locomotives maintain AC traction motors but are derated to 4,300 horsepower for improved reliability and fuel efficiency in heavy-haul applications. Launched in 2016 at Norfolk Southern's Juniata Locomotive Shop in , the program initially processed units there before transferring final assembly to Progress Rail's facility. The inaugural SD70ACUs, numbered 7248 and 7283, entered service in January 2016, marking the start of a multi-year effort to modernize aging fleet assets. By May 2019, all 110 planned units for Southern—numbered 7229–7339 and sourced primarily from ex-Union Pacific SD9043MAC cores acquired in 2014—had been completed and released to revenue service. As of November 2025, Norfolk Southern maintains 45 active SD70ACU units in its roster, with 18 in storage, reflecting ongoing amid retirements and sales of excess units to other operators. These locomotives are predominantly assigned to intermodal operations, including double-stack trains, where their robust and updated controls provide superior and reduced maintenance needs compared to pre-rebuild predecessors. The rebuild approach proves highly cost-effective, with each unit estimated at around $1.03 million—roughly half the cost of a comparable new —allowing for extended operational viability without full replacement.

SD70ACC

The SD70ACC is a series of rebuilt locomotives developed by Norfolk Southern Railway in partnership with Progress Rail, converting early DC-traction SD70 units into modernized AC-traction machines while retaining the core 4,300 horsepower EMD 16-710G3B prime mover. Announced in early 2017, the program targeted 52 high-mileage SD70s built between 1993 and 1995, which had accumulated extensive service on Norfolk Southern's freight network, to extend their operational life through targeted upgrades focused on safety, efficiency, and crew accommodations. The first units, NS 1800 and 1801, entered revenue service in late 2018 after rebuilds at Progress Rail's Muncie, Indiana facility, with the full fleet completed by 2019. Key modifications in the SD70ACC rebuild emphasized cab and control enhancements without a full propulsion overhaul, distinguishing it from more extensive AC conversions. Each unit received a new wide-nose safety cab designed to meet current standards, replacing the original narrow "Spartan" cab to significantly improve comfort, , and protection during operations. The program integrated (PTC) systems for enhanced safety compliance, along with an upgraded EM2000 and CCB II computer-controlled air brakes for better performance and reliability. Existing HT-C trucks were refurbished with new AC traction motors (model D87BTR), enabling smoother acceleration, higher , and reduced maintenance compared to the original DC setup, while the overall DC-to-AC transition boosted and . These rebuilds were specifically selected from Norfolk Southern's fleet of standard-cab SD70s, which lacked the passenger-oriented wide cab of the related SD70M model, allowing the SD70ACC to address fatigue issues in long-haul freight service through ergonomic improvements like better seating, noise isolation, and climate control. As of November 2025, all 52 SD70ACC units remain on the active roster, with approximately 33 in operational service and 19 in storage, supporting general freight duties across the railroad's 19,500-mile network, though fleet planning discussions have begun amid broader locomotive retirement strategies to modernize the roster further.

SD70MACe

The SD70MACe is a rebuild variant of the EMD SD70MAC locomotive, developed by in collaboration with the to modernize older AC-traction units for continued heavy-haul service. The program began in the mid-2010s, with the first units emerging from 's Tacoma, Washington facility around 2016, focusing on electrical and cooling system upgrades to address reliability issues in the original components and enhance performance in high-temperature environments like the coal routes. Key features of the SD70MACe include the replacement of the outdated inverters and traction motors with more efficient electronics and motors sourced from the SD70ACe , improving traction control and reducing failure rates associated with the legacy equipment. The locomotives retain the original SD70MAC frame and 16-cylinder 710G3B but receive a refreshed Phase 2 SD70ACe-style carbody for better and larger radiators to boost , particularly suited for and hot-climate operations where overheating was a common issue with unmodified SD70MACs. These changes extend the units' service life by 10-15 years while bridging the technological gap between early AC locomotives and modern emissions-compliant models, without requiring a full engine repower. BNSF has rebuilt approximately 24 SD70MACe units, primarily from the 9700-series ex-Burlington Northern locomotives, as of 2025, using them in helper and roles on and intermodal trains. The rebuild process recycles up to 90% of the original components, offering significant cost savings—upward of $2 million per unit compared to purchasing new locomotives—making it an economical option for fleet renewal amid evolving EPA emissions standards. This program allows BNSF to leverage the proven durability of the SD70MAC platform while incorporating ACe-era efficiencies, such as better controls for optimized fuel use and reduced downtime.

SD70MACH

The SD70MACH represents a heavy rebuild program initiated by Progress Rail (a Caterpillar subsidiary and successor to Electro-Motive Diesel) to extend the service life of aging SD70MAC freight locomotives for passenger applications. Approved by the Metra board in February 2019, the initial contract covered the remanufacture of 15 units at a cost of $70.9 million, sourced primarily from former Kansas City Southern and Transportación Ferroviaria Mexicana (TFM) SD70MACs built between 1993 and 2004. These rebuilds incorporate comprehensive engine and frame overhauls, transforming wide-cab, six-axle AC-traction freight units into efficient commuter locomotives capable of speeds up to 85 mph. All 15 initial units had been delivered by late 2024, with an additional nine ordered in 2024 under the original contract options for up to 27 more (exercised for these nine, with potential for 18 additional), for a total of 24 units as of November 2025 and potential maximum of 42. Key features of the SD70MACH include new or remanufactured EMD 16-710G3B engine cores rated at 4,000 horsepower, which undergo full disassembly, inspection, and upgrades to enhance reliability and . Suspension systems are upgraded to a B1-1B , with the outer four axles powered for traction and the inner two unpowered to support (HEP) generation without compromising performance. The original AC traction system is retained, including upgraded inverters that divert power for 480 kW HEP to supply passenger cars, while controls and electronic braking ensure compatibility with (PTC) and cab signaling. All components—ranging from alternators to cooling systems—are either refurbished to original specifications or replaced with new equivalents, resulting in units that meet EPA Tier 3 emissions standards and operate as the cleanest-burning locomotives in Metra's fleet. This rebuild adheres to rigorous industry standards for a major overhaul, effectively resetting the mechanical life of the base units for an additional 20 to 30 years of service, avoiding the need for complete new-build acquisitions amid fluctuating s. The program emphasizes by repurposing existing 1,109 SD70MACs originally produced, reducing waste and emissions compared to from scratch. In , demand for similar heavy rebuilds has grown due to ongoing global disruptions affecting new production, prompting railroads like to accelerate timelines and extend options for further units, with remaining deliveries projected through 2026–2027.

SD70ICC

The SD70ICC is a specialized rebuild variant of the EMD SD70 series, produced by Progress Rail starting in 2023, with two units completed for Norfolk Southern (NS 1250–1251) from former SD70M-2 locomotives incorporating AC traction conversion for improved efficiency and performance in freight operations. Additional units include two for Canadian National (CN 8900–8901), for a total of approximately four known units as of 2025. Key features include customized control systems such as the EM2000 for precise handling, low-emission retrofit kits compliant with EPA standards to reduce environmental impact, and integrated remote diagnostics for proactive . The design emphasizes durability with an isolated that minimizes noise and vibration, enhancing crew safety and comfort during extended shifts. Unique to the SD70ICC are adaptations for heavy-duty freight applications, including enhanced for precise control.

Operators

North American operators

Burlington Northern Santa Fe (BNSF) operates the largest fleet of SD70 series locomotives in , with approximately 1,000 units as of 2024, primarily consisting of SD70MAC and SD70ACe variants used for heavy-haul services such as trains and intermodal operations across its western U.S. network. These locomotives are integral to BNSF's high-volume freight movements, leveraging their 4,000 horsepower and AC traction for efficient power in distributed configurations on long-haul routes. Union Pacific (UP) maintains around 700 SD70 series units as of 2025, mainly SD70M and SD70ACe models, deployed in intermodal and general merchandise traffic to support its extensive transcontinental operations. Under precision scheduled railroading (PSR) initiatives, UP has accelerated retirements of older units while rebuilding SD70s to extend their service life, aiming for operational efficiency amid fluctuating volumes as of 2025. Norfolk Southern (NS) rosters about 400 SD70 variants as of 2025, including rebuilt SD70ACe and SD70M-2 units, focused on mixed freight and transport in the eastern U.S. NS emphasizes rebuild programs, converting DC-traction SD70s to AC for improved reliability and performance on hump yards and unit trains. Canadian National (CN) utilizes roughly 300 SD70 series locomotives as of 2025, such as SD70M-2 and SD70ACe models, for diverse applications including bulk commodities and intermodal in and the northern U.S. Following post-2020 mergers and network expansions, CN integrates these units into streamlined operations, prioritizing fuel efficiency and emissions compliance. Canadian Pacific Kansas City (CPKC), formed by the 2023 merger, combines fleets from CP and KCS, incorporating over 200 SD70 variants as of 2025 like SD70ACU rebuilds for cross-border freight and energy transport. The integration has optimized SD70 usage for longer trains under PSR-like models, enhancing connectivity from Canada to Mexico by 2025. Regional and short-line operators, such as those under Genesee & Wyoming (G&W), collectively manage about 50 SD70 series units as of 2024, often leased or acquired second-hand for switching and local service on secondary lines. These locomotives provide versatile power for lighter traffic, supporting industrial and agricultural shipments while complying with emissions upgrades.

International operators

In , operates a fleet of approximately 182 EMD SD70ACe locomotives in the region for heavy-haul service, including specialized SD70ACe/LC and SD70ACe/LCi variants adapted for local track conditions, higher loads, and stricter emissions requirements. These locomotives, many built between 2008 and 2014, provide 4,300 horsepower and are configured for operations on trains exceeding 30,000 tons. In , mining operator Vale deploys SD70 series locomotives on its Estrada de Ferro Carajás and Estrada de Ferro Vitória a Minas lines for transport, with adaptations for meter-gauge (1,000 ) tracks. The fleet includes over 100 units as of 2025, such as the SD70ACe and the eight-axle SD70ACe-BB model introduced in 2015, which distributes weight across additional axles to meet limits while delivering 4,300 horsepower for up to 20,000 tons. These locomotives feature EMD's 710G3B engine and AC traction for reliability in tropical conditions. In , maintains one of the largest international fleets of SD70ACe locomotives, totaling 132 units as of , used for intermodal and bulk freight across its 8,000-mile network. These 4,300-horsepower AC-traction units, many delivered between 2005 and 2015, support high-volume traffic including automotive parts and minerals, with ongoing maintenance to ensure compliance with emissions standards. In , exports include the SD70ACe/LW variant for wide-gauge (1,520 ) operations; for example, Mongolia's Tavantolgoi-Gashuunsukhait Railway received 16 units in 2024 for coal transport in harsh environments. These locomotives incorporate low-water cooling systems and extended tanks for extended runs. In , supplied a 2TE3250 (based on the SD70ACe platform) to Yakutia Railway in for testing in subarctic conditions, though no large-scale deployment followed.

Preservation

Preserved SD70MAC units

The EMD SD70MAC, introduced in as one of the first production locomotives to feature AC traction motors for freight service, has seen limited preservation efforts due to the model's relatively recent production and ongoing operational use by many railroads. By late , at least one notable example has been preserved, highlighting the model's role in the industry's shift from DC to AC traction technology, which improved , , and maintenance efficiency. Burlington Northern Santa Fe (BNSF) Railway SD70MAC No. 9400, built in 1993 as the original Burlington Northern No. 9400, holds particular historical significance as the first production American freight diesel equipped with AC traction motors. Dedicated in January 1994 in , alongside other historic locomotives, it demonstrated the viability of AC drive systems, paving the way for their dominance in heavy-haul railroading by the early 2000s. After years of service, including time in storage at BNSF's Ravenna, Nebraska yard, the locomotive was donated to the Illinois Railway Museum (IRM) in Union, Illinois, in July 2025. At IRM, No. 9400 arrived unrestored and non-operational, weighing 415,000 pounds and measuring 74 feet in length with its original 4,000-horsepower 16-710G3B . The plans to restore it to operating condition and return it to its as-built maroon-and-black Burlington Northern livery, emphasizing its pioneering status among EMD's wide-cab SD series. Donations are being solicited to fund the multi-year restoration , which will allow public operation on IRM's mainline. This preservation effort underscores the SD70MAC's transitional importance in locomotive design, bridging earlier DC-powered models like the SD60MAC prototype with later AC-dominant fleets.

Preserved SD70ACe units

A notable SD70ACe has been preserved for its historical and educational value, particularly exemplifying advancements in diesel-electric technology and special commemorative liveries. One prominent example is Union Pacific No. 4141, an SD70ACe built in 2005 and specially painted in 2018 to resemble the colors of in honor of former President . This unit led the presidential funeral train from Spring to , in December 2018 and was donated to the George H.W. Bush Presidential Library & Museum, where it was placed on permanent static display following a formal unveiling on May 2, 2024. The preservation of No. 4141 highlights the SD70ACe's role in modern freight operations while serving as an exhibit on presidential history and railroading's cultural impact. As of 2025, preserved SD70ACe units remain limited in number, with efforts focused on those that demonstrate key engineering features or unique historical contexts rather than widespread retirement examples. Export preservations of SD70ACe variants are rare, with most examples remaining in active service abroad.

Variant images

The variant images below illustrate the design progression across key models in the EMD SD70 series, emphasizing changes in cab configuration and radiator placement that reflect advancements in traction technology and safety standards. SD70 (DC-powered, introduced ): This model typically features a standard EMD safety cab with a sloped nose and two-piece windshield, paired with longitudinal radiator intakes along the sides of the long hood for DC traction motor cooling. The design prioritizes simplicity and compatibility with earlier EMD six-axle locomotives. SD70MAC (AC-powered, introduced 1993): Building on the SD70, this variant adopts a wide-nose cab for improved visibility and , while introducing a prominent transverse section at the rear with larger, centralized cooling fans to support AC traction motors. The wide cab includes flared corners and a more angular profile compared to the standard cab. SD70ACe (AC-powered, introduced 2005): The SD70ACe refines the wide cab with rectangular window glazing and a more streamlined nose derived from late SD90MAC designs, alongside flared housings that extend forward for enhanced airflow in high-horsepower AC applications. This iteration marks a shift toward modern aesthetics and emissions compliance. These visuals demonstrate how cab width and radiator configurations evolved to accommodate AC traction demands and regulatory updates without altering the core 4,000–4,300 hp 16-710 engine platform.

Operational photographs

A SD70MAC locomotive, numbered 9597 in the legacy Burlington Northern scheme, leads a loaded ascending Crawford Hill west of Belmont, , on May 20, 2006, illustrating the model's prowess in heavy-haul coal service across the . Another operational scene features BNSF SD70MAC No. 9939 powering a westbound through , on June 10, 2006, with SD70MAC No. 9650 providing additional , highlighting the locomotives' integration into long-distance unit trains. Union Pacific SD70ACe No. 1989, the & Western heritage unit, is displayed at its unveiling event near , Colorado, on June 17, 2006, highlighting the variant's role in commemorative paint schemes. In a heritage formation, UP SD70ACe No. 8444 leads a consist of six Union Pacific heritage locomotives for the first time, captured during a special photo shoot event, underscoring the model's role in commemorative gatherings. A pair of SD70ACe-T4 locomotives leads a Union Pacific through , as documented in early operations, exemplifying the Tier 4 compliant variant's emissions-reduced performance in contemporary heavy freight service. BNSF SD70MAC No. 9604 trails in a mixed freight consist at New Hope, , on March 27, 2023, showing the enduring utility of rebuilt and original SD70 units in cross-country hauls.

References

  1. https://www.trains.com/trn/railroads/locomotives/the-evolution-of-emds-sd70-series-locomotives/
  2. https://www.american-rails.com/926307.html
  3. https://www.progressrail.com/en/Segments/Locomotive/Locomotives/FreightLocomotives/SD70ACe.html
  4. https://www.railroadjunction.net/locomotives-detail.php?locoID=emd-sd70-diesel-electric-locomotive
  5. https://www.progressrail.com/en/Company/AboutUs/EMD100/1990s.html
  6. https://ww2.arb.ca.gov/sites/default/files/classic/research/apr/past/a032-169&92-917a.pdf
  7. https://www.american-rails.com/710.html
  8. https://www.progressrail.com/en/Segments/Locomotive/Locomotives/FreightLocomotives/SD70ACS.html
  9. https://www.thedieselshop.us/Data%20EMD%20SD70.HTML
  10. https://www.federalregister.gov/documents/2006/06/28/06-5667/locomotive-crashworthiness
  11. https://www.ecfr.gov/current/title-49/subtitle-B/chapter-II/part-229/subpart-D
  12. https://railroads.dot.gov/sites/fra.dot.gov/files/fra_net/3990/DOT-FRA-ORD-03-05.pdf
  13. https://rosap.ntl.bts.gov/view/dot/15100/dot_15100_DS1.pdf
  14. https://www.progressrail.com/en/Segments/Locomotive/Locomotives/FreightLocomotives/SD70ACe-T4.html
  15. https://forum.trains.com/t/more-dc-to-ac-for-ns/324104
  16. https://www.trains.com/trn/railroads/locomotives/north-americas-endangered-class-i-locomotives-in-2024/
  17. https://www.thedieselshop.us/CN.HTML
  18. https://www.railroadfan.com/phpbb/viewtopic.php?t=40359&start=380
  19. https://www.trains.com/trn/railroads/locomotives/emd-sd70mac-profile/
  20. https://trainiax.net/mephase-emdsd70mac.php
  21. https://www.railwayage.com/mechanical/locomotives/metras-macs-from-freight-haulers-to-commuter-service/
  22. https://www.alaskarails.org/glance/sd70mac/gm-features.html
  23. https://www.railwayage.com/mechanical/locomotives/progress-rail-completes-sd70-mach-deliveries-to-metra/
  24. https://www.csx.com/index.cfm/about-us/csx-advances-freight-efficiency-with-sd-70-locomotive-rebuild-program/
  25. https://www.american-rails.com/20106364.html
  26. https://www.railwayage.com/mechanical/locomotives/engines-of-change/
  27. https://www.progressiverailroading.com/mechanical/article/Locomotive-Manufacturers-Offer-Information-on-their-Fuel-Saving-Models--21139
  28. https://trainiax.net/mephase-emdsd70ace.php
  29. https://www.railwayage.com/mechanical/locomotives/ferromex-ferrosur-add-to-sd70ace-fleet/
  30. http://www.nsdash9.com/rosters/1000.html
  31. https://www.athearn.com/on/demandware.static/Sites-athearn-us-Site/Sites-athearn-us-Library/default/blog-pdfs/01_GEN_SD70M-2_012921.pdf
  32. https://www.railwayage.com/news/take-a-tour-of-emds-sd70ace-t4/
  33. http://s7d2.scene7.com/is/content/Caterpillar/C10678841
  34. https://www.thedieselshop.us/UP.HTML
  35. https://trains-and-locomotives.fandom.com/wiki/EMD_SD70ACe
  36. https://www.reddit.com/r/railroading/comments/1e7p8uk/engineers_opinions_on_the_sd70ace_series_good_to/
  37. https://www.trains.com/trn/railroads/locomotives/the-future-of-the-locomotive/
  38. https://www.progressrail.com/en/Segments/Locomotive/Locomotives/FreightLocomotives/SD70ACe-LCi.html
  39. https://www.railexpress.com.au/emd-technology-highlights/
  40. https://www.railwaygazette.com/freight/bhp-billiton-places-large-heavy-haul-locomotive-order/36726.article
  41. https://www.pilbararailways.com.au/bhp/sd70ace.php
  42. https://www.progressrail.com/en/Company/Locations/SouthAmerica.html
  43. https://www.railwaygazette.com/freight/desert-locomotives-delivered-to-saudi-arabia/35236.article
  44. https://www.railwayage.com/news/emd-wins-new-order-from-mauritania/
  45. http://s7d2.scene7.com/is/content/Caterpillar/C10669493
  46. https://www.gccrailway.com/sd70acs-locomotives-for-uae-oman-railway-project/
  47. https://www.progressrail.com/en/Segments/Locomotive/Locomotives/FreightLocomotives/SD70ACe-BB.html
  48. https://s7d2.scene7.com/is/content/Caterpillar/CM20170915-63120-44370
  49. https://trainspo.com/model/5383/
  50. https://www.progressrail.com/en/Company/News/PressReleases/VLItoAcquireEightEMDLocomotivesfromProgressRailtoTransportCargoontheCentroAtlanticaRailway.html
  51. https://www.railwayage.com/news/supply-side-wabtec-cummins-vli-progress-rail-parsons-alstom/
  52. https://www.progressiverailroading.com/rail_industry_trends/news/Australian-mining-firm-orders-13-SD70ACe-locomotives-from-EMD--7645
  53. https://www.aurizon.com.au/news/2024/aurizon-secures-funding-to-develop-next-generation-freight-trains-using-renewable-energy
  54. http://www.nsdash9.com/rosters/1175.html
  55. https://www.ecfr.gov/current/title-40/chapter-I/subchapter-U/part-1033
  56. https://www.railwayage.com/regulatory/carb-passes-new-in-use-locomotive-regulation/
  57. https://www.railwayage.com/mechanical/locomotives/new-emd-power-for-mongolia/
  58. https://rollingstockworld.com/lrv/latest-rolling-stock-procurements-and-supplies-progress-rail-ltg-cargo-electrotrans/
  59. https://www.conquerornetwork.com/news-conqueror/2025/10/03/conqueror-ulaanbaatar-successfully-delivers-16-new-locomotives/
  60. https://www.railwaygazette.com/traction-and-rolling-stock/progress-rail-locomotive-on-test-in-russia/59027.article
  61. https://www.railvolution.net/news/emd-locomotive-at-yakutian-railways
  62. https://rollingstockworld.com/locomotives/progress-rail-was-unable-to-offer-yakutia-railways-locomotives-at-the-required-price/
  63. https://www.pwrs.ca/announcements/view.php?ID=17435
  64. http://www.nsdash9.com/NSJuniata2016/nsjls2.html
  65. https://www.trains.com/pro/mechanical/locomotives/10-altoona-sd70acu/
  66. https://modelrailroadnews.com/canadian-national-and-norfolk-southern-sd70acu/
  67. http://www.nsdash9.com/roster.html
  68. https://www.youtube.com/watch?v=pDO3DOlsN5k
  69. https://www.trainorders.com/discussion/read.php?2,4635646
  70. https://www.trainorders.com/discussion/read.php?2,4223213
  71. http://www.nsdash9.com/rosters/1800.html
  72. https://www.trains.com/pro/mechanical/locomotives/12-norfolk-southern-sd70acc-leads-train-into-chicago-for-first-time/
  73. https://www.trainorders.com/discussion/read.php?2,4519622
  74. http://www.nsdash9.com/atroster.html
  75. https://www.progressrail.com/en/Segments/Locomotive/Locomotives/RepoweredLocomotives.html
  76. https://www.trainorders.com/discussion/read.php?1,3952691
  77. https://www.thedieselshop.us/BNSF.HTML
  78. https://www.railwayage.com/mechanical/locomotives/first-look-metras-sd70mach/
  79. http://www.nsdash9.com/rosters/1250.html
  80. https://www.facebook.com/nsdash9/posts/sd70icc-rebuildsprogress-rail-has-completed-a-pair-of-ns-sd70icc-rebuilds-from-a/752126043588298/
  81. https://www.instagram.com/p/C-gNVa_xdFw/
  82. https://www.railwayage.com/freight/class-i/up3q25-continued-improvements-in-pursuit-of-whats-possible/
  83. https://www.railwayage.com/mechanical/locomotives/ac-dc-dynamics/
  84. https://www.progressiverailroading.com/news/?m=3&y=2025
  85. https://railroadfan.com/wiki/index.php/CPKC_Locomotive_Roster
  86. https://www.railwayage.com/freight/class-i/class-i-briefs-bnsf-csx-ns-3/
  87. https://www.trains.com/trn/railroads/locomotives/genesee-wyoming-upgrades-fleet/
  88. https://www.railcan.ca/wp-content/uploads/2022/11/SPARK-RAC-LEM-REPORT-2022-EN8-1.pdf
  89. https://www.thedieselshop.us/FXE.HTML
  90. https://railmarket.com/news/rolling-stock/20204-first-new-progress-rail-locomotives-delivered-for-mongolia-s-tavan-tolgoi-railway
  91. https://www.irm.org/in-the-news/sd70mac-acquired-by-irm/
  92. https://www.irm.org/player/bn9400/
  93. https://www.trains.com/trn/railroads/heritage-rail/railroad-museums/first-production-ac-traction-diesel-donated-to-illinois-railway-museum/
  94. https://railfan.com/bnsf-donates-historic-sd70mac-to-irm/
  95. https://www.up.com/about-us/history/heritage-fleet/commemorative/ghw-bush-4141
  96. https://georgeandbarbarabush.org/news/george-bush-presidential-library-museum-unveils-4141-locomotive-in-new-addition
  97. https://www.up.com/news/heritage/4141-permanent-display-it-240612
  98. http://www.rrpicturearchives.net/locopicture.aspx?id=4015
  99. http://www.rrpicturearchives.net/locopicture.aspx?id=84290
  100. https://www.railpictures.net/photo/827983/
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