Hubbry Logo
EMD GP40EMD GP40Main
Open search
EMD GP40
Community hub
EMD GP40
logo
8 pages, 0 posts
0 subscribers
Be the first to start a discussion here.
Be the first to start a discussion here.
EMD GP40
EMD GP40
EMD GP40
View on Wikipedia
from Wikipedia
EMD GP40
A Guilford Rail System GP40 in Wells, Maine.
Type and origin
Power typeDiesel-electric
BuilderU.S., General Motors, Electro-Motive Division (EMD)
Canada, General Motors Diesel (GMD)
ModelGP40, GP40P, GP40TC
Build dateNovember 1965 – December 1971
Total produced1,242
Specifications
Configuration:
​
 • AARB-B
 • UICBo'Bo'
Gauge4 ft 8+1⁄2 in (1,435 mm) standard gauge
Prime moverEMD 16-645E3
Engine typeV16 diesel
Cylinders16
Performance figures
Power output3,000 hp (2.24 MW)
Career
LocaleNorth America

The EMD GP40 is a 4-axle diesel-electric locomotive built by General Motors' Electro-Motive Division between November 1965 and December 1971. It has an EMD 645E3 16-cylinder engine generating 3,000 hp (2,240 kW).

The GP40 is 3 feet (0.914 m) longer than its EMD 567D3A-engined predecessor, the GP35, and distinguished visually by its three 48-inch radiator fans at the rear of the long hood, while the GP35 has two large fans and a smaller one in between. It was built on a 55 ft (16.76 m) frame; the GP35 was built on a 52 ft (15.85 m) frame - as was the GP7, 9, 18, and 30. The difference in length can be seen in the GP40's ten handrail stanchions compared to the GP35's nine.[1]

1,187 GP40s were built for 28 U.S. railroads; 16 were built for one Canadian carrier, Canadian National; and 18 were built for two Mexican carriers, Ferrocarril Chihuahua al Pacífico and Ferrocarriles Nacionales de México. 60 units were built with high-short-hoods and dual control stands for Norfolk & Western Railway. Two passenger versions, the GP40P and GP40TC, were also built, but on longer frames to accommodate steam generators and HEP equipment.

On January 1, 1972, the GP40 was discontinued and replaced by the GP40-2, which has a modular electrical system and a few minor exterior changes.

Images

[edit]

Original owners

[edit]
Railroad Quantity Road Numbers Notes
Atlanta and West Point Railroad 7 726-732
Atlantic Coast Line Railroad 15 915-929 To Seaboard Coast Line 1500-1514
Baltimore and Ohio Railroad 161 3684-3779, 4000-4064
Chesapeake and Ohio Railway 50 3780-3794, 4065-4099 3794 was the last GP40 built
Ferrocarril Chihuahua al Pacífico 8 1000-1007
Chicago, Burlington and Quincy Railroad 40 170-189, 620-639
Canadian National Railway 16 4002-4017 Built by General Motors Diesel (GMD) for use in Canada
De Queen and Eastern Railroad 1 D-7
Denver and Rio Grande Western Railroad 43 3051-3093
Detroit, Toledo and Ironton Railroad 6 400-405
Florida East Coast Railway 10 401-410
Georgia Railroad and Banking Company 4 751-754
Illinois Central Railroad 75 3000-3074
Louisville and Nashville Railroad 30 3000-3029
Milwaukee Road 72 153-199, 2047-2071 2068-2071 were EMD warranty loaners
Missouri–Kansas–Texas Railroad 61 170-230
Norfolk and Western Railway 60 1329-1388 High-nose
Ferrocarriles Nacionales de México 10 8400-8409
New York Central Railroad 105 3000-3104 3036 was the first GP40 built. To Penn Central.
Penn Central Transportation Company 170 3105-3274 3260-3274 were EMD warranty loaners 11-26
Richmond, Fredericksburg and Potomac Railroad 7 121-127
Chicago, Rock Island and Pacific Railroad 77 340-396, 4700-4719 Financed by Union Pacific, because of the proposed UP-RI merger
Seaboard Air Line Railroad 51 600-650 To Seaboard Coast Line 1515-1565
Seaboard Coast Line Railroad 70 1566-1635
Soo Line Railroad 4 732-735
St. Louis Southwestern Railway (Cotton Belt) 8 7600-7607 All were rebuilt into the model GP40R and renumbered 7960-7967.[2]
Texas, Oklahoma and Eastern Railroad 3 D-12 - D-14
Toledo, Peoria and Western Railway 1 1000 Ex-EMD warranty loaner
Western Railway of Alabama 7 701-707
Western Maryland Railway 5 3795-3799
Western Pacific Railroad 44 3501-3544 3501-3516 built with large Pyle single headlight
Totals 1,221

GP40P

Railroad Quantity Road numbers Notes
Central Railroad of New Jersey 13 3671-3683
Totals 13

GP40TC

Railroad Quantity Road numbers Notes
Canadian National Railway 8 600-607
Totals 8

Rebuilds

[edit]

GP40N

[edit]

Union Pacific has rebuilt 129 of their GP40's and GP40-2's into GP40N's at their Jenk's shop. These units received a microprocessor control system to increase adhesion, control options, and extend the life of the locomotive.[3][4]

GP40R

[edit]

The St. Louis Southwestern Railway (Cotton Belt) ordered eight locomotives from EMD but rebuilt all eight of them into GP40R's between January and June of 1982.[2]

GP22ECO

[edit]
Main article: EMD GP22ECO

The GP22ECO is a locomotive built from recycled GP40/GP40-2 parts. The frame, trucks, and carbody are refurbished, while the 16-645 engine is replaced with a new 8-710-ECO engine. The electrical system is replaced with a modern microprocessor-based system. Horsepower is reduced to 2,150 due to the smaller engine.

Preservation

[edit]
  • Penn Central #3118 (ex-Conrail, ex-DRGW) was purchased by the Austin Steam Train Association in 2024. The locomotive is currently in its Horizon Rail livery and numbered 3134. The engine has also been updated with a microprocessor, making it a GP40-3.

See also

[edit]

References

[edit]
[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

EMD GP40

View on Grokipedia
from Grokipedia
The EMD GP40 is a four-axle, 3,000-horsepower diesel-electric general-purpose locomotive produced by the Electro-Motive Division (EMD) of from November 1965 to December 1971. It features a turbocharged 16-cylinder EMD 645E engine, marking an upgrade in power and efficiency over earlier models like the GP35, and was designed primarily for freight service but also adapted for passenger use across North American railroads. Development of the GP40 began in the mid-1960s as EMD sought to meet growing demands for higher horsepower in road-switching duties, with the first unit delivered to the in November 1965. A total of 1,221 units were built, making it one of EMD's most successful four-axle locomotives, and it remained in production until the introduction of the dash-2 series in 1972. The model gained popularity for its reliability and versatility, serving major carriers such as the Southern Pacific, Union Pacific, and Canadian National, with many units still operational as of 2025 in freight, switching, and excursion roles after rebuilds and upgrades. Key specifications include a length of 59 feet 2 inches, a weight of 245,000 pounds, and a top speed of 65 mph, powered by the 645E with a 62:15 gear ratio for balanced performance in yard and mainline operations. It employs HTB high-adhesion trucks in a B-B configuration, Westinghouse 26L air brakes, and for enhanced control, contributing to its reputation as a rugged workhorse in the transition era of dieselization. Variants like the GP40-2, produced from 1972 to 1986, incorporated improvements such as an improved and electrical systems for better , extending the lineage's influence into modern railroading.

Design and Development

Background

The EMD GP40 emerged as an evolution of earlier four-axle General Purpose (GP) locomotives, such as the GP35, to meet the escalating demands for higher horsepower in North American freight service during the mid-1960s. The 16-645E3 engine was developed as an upgrade from the 567 series, with testing beginning in an SD40 demonstrator locomotive in July 1964. As railroads sought greater power to handle heavier trains and longer hauls amid post-World War II economic expansion, Electro-Motive Division (EMD) focused on enhancing output while maintaining the reliable B-B truck configuration favored for versatility on secondary lines and yard operations. In June 1965, EMD announced the GP40 as part of its ambitious "40 Series" lineup, a strategic response to intensifying competition from General Electric's Universal series, including the 3,000 hp U30C introduced shortly thereafter. This development positioned the GP40 as a direct competitor in the race for market dominance, emphasizing EMD's established engineering prowess against GE's rising challenge in the sector. A pivotal design choice was the integration of the turbocharged 16-645E3 prime mover, delivering 3,000 horsepower for superior freight performance without shifting to a six-axle design. Production began in November 1965 at EMD's LaGrange, Illinois facility and continued through December 1971, resulting in 1,221 standard units constructed. Special variants such as the GP40P and GP40TC were also produced during this period (see Production section). The GP40's production run concluded with the introduction of the GP40-2 in 1972, which incorporated the Dash-2 series' modular electrical controls for improved reliability and addressed evolving emissions standards through refined engine tuning.

Technical Specifications

The EMD GP40 is a four-axle (B-B) diesel-electric equipped with a turbocharged, two-stroke EMD 16-645E3 prime mover, a 16-cylinder V configuration with a bore of 9 1/16 inches and stroke of 10 inches, yielding a total displacement of 10,320 cubic inches. This delivers a rated power output of 3,000 horsepower (2,237 kW) for traction, operating at a maximum of 900 RPM and an idle minimum of 275 RPM. The locomotive's electrical transmission features an AR10 alternator as the main generator, powering four GM D77 series DC traction motors—one per axle—for efficient power delivery to the wheels. A 62:15 gear ratio enables a top speed of approximately 65 mph (105 km/h), while is standard for enhanced control during deceleration. The includes an eight-notch throttle for precise power modulation and multiple-unit (MU) capability, allowing operation of up to 12 units in consists for distributed power. Built on standard gauge track of 4 ft 8½ in (1,435 mm), the GP40 measures 59 ft 2 in (18.03 m) in length over the coupler pulling faces, 10 ft 2½ in (3.11 m) in width over grab irons, and 15 ft 2½ in (4.64 m) in height above the rail. It rides on two HTB four-wheel trucks with a 9 ft (2.74 m) wheelbase per truck and 40 in (1,016 mm) wheel diameter, contributing to a loaded operating weight of 255,000–260,000 lb (115,700–117,900 kg). Tractive effort is rated at 62,500 lbf (278 kN) for starting (at 25% ) and 54,700 lbf (243 kN) continuous at 11.1 mph (17.8 km/h), providing robust for freight hauling. Fuel capacity varies by configuration from 1,700 to 3,600 US gal (6,400 to 13,600 L) to support extended runs, complemented by a 56 cu ft (1.6 m³) sandbox for traction enhancement via sand delivery to the rails.
SpecificationDetails
Prime MoverEMD 16-645E3, turbocharged, 10,320 cu in displacement
Power Output3,000 hp (2,237 kW)
Wheel Arrangement (4 axles, 40 in diameter)
Dimensions (L × W × H)59 ft 2 in × 10 ft 2½ in × 15 ft 2½ in (18.03 × 3.11 × 4.64 m)
Weight255,000–260,000 lb (115,700–117,900 kg)
Tractive EffortStarting: 62,500 lbf (278 kN); Continuous: 54,700 lbf (243 kN) @ 11.1 mph
Electrical SystemAR10 ; 4 × D77 traction ; 62:15 gear ratio
Fuel/Sand Capacity1,700–3,600 gal (6,400–13,600 L); 56 cu ft (1.6 m³)
Control8-notch throttle; MU up to 12 units

Production

Original Production Run

The original production run of the EMD GP40 occurred at the Electro-Motive Division's manufacturing plant in LaGrange, Illinois, spanning from November 1965 to December 1971. This facility served as the primary site for assembling the locomotive's key components, including the turbocharged 16-645E3 engine. A total of 1,243 standard GP40 units were built during this period, primarily for domestic North American railroads. Serial numbers for these units generally ranged from 30937 to 73688, with production orders assigned sequential builder numbers reflecting the assembly sequence at LaGrange. The design emphasized reliability for freight service, incorporating a 3,000 horsepower rating that became a benchmark for four-axle road-switchers. Production peaked in the mid-1960s, with output tapering toward the end of the run as railroads shifted toward higher-horsepower six-axle models like the SD40. While exact annual figures varied by order demand, the locomotive's popularity led to steady manufacturing through 1967 before gradual decline. at the LaGrange plant included rigorous assembly inspections and performance testing, such as dynamometer runs to verify engine output, function, and overall electrical integrity prior to delivery. These procedures ensured compliance with railroad specifications and minimized field failures, contributing to the model's long-term operational success.

Special and Export Variants

The GP40P was a specialized variant of the , featuring modifications for commuter service including a and extended frame. Thirteen units were constructed in late 1968 for the , though ordered in connection with operations and later absorbed into Penn Central. These locomotives included a Vapor brand rated at 800 pounds per hour for train heating, a reduced capacity of 1,100 gallons to accommodate the equipment, and modified cabs with improved visibility for runs. The GP40TC represented a unique adaptation as unpowered control cab units, designed to provide cab control for push-pull passenger operations without a prime mover. Eight such units were built between 1966 and 1968 for in , utilizing GP40 mechanical components like trucks and electrical systems but omitting the 16-cylinder 645E3 engine to reduce weight and cost. These cabs allowed engineers to operate trains from the rear car, enhancing efficiency on commuter routes around . Export models of the GP40 incorporated adaptations for international operators, with 16 units delivered to Canadian National in 1967 and 14 to Mexican carriers between 1966 and 1967. The Canadian units, built by in , featured high short hoods for improved crew protection and visibility in cold weather conditions. Mexican exports included tropicalized cooling systems with enhanced radiators to handle high temperatures and humidity; these comprised 10 powered locomotives to (8400-8409) and 4 to Chihuahua Pacífico (1004-1007). These variants differed from the standard GP40 primarily in hood configuration and environmental adaptations, while retaining the core 3,000 horsepower EMD 645E3 turbocharged engine where powered. Including the GP40P and GP40TC variants, total GP40 production reached approximately 1,242 units.

Operational History

Original Operators

The EMD GP40 was acquired by numerous North American railroads during its production run from to , with the bulk of orders placed by major U.S. Class I carriers for high-speed road freight and helper duties on challenging grades. These locomotives were particularly valued for their reliable 3,000 horsepower 16-cylinder 645-series engine, which provided superior performance in general merchandise trains and over mountain divisions compared to earlier GP35 models. Initial deployments focused on mainline operations, with some units assigned to hump yard service for tasks. A total of 1,221 units were produced, distributed among 28 U.S. railroads (1,187 units), one Canadian carrier (16 units), and two Mexican carriers (18 units). The largest U.S. fleet belonged to the and its successor Penn Central, which collectively operated 300 GP40s, including 25 from the Pennsylvania Railroad (1966), 105 inherited from the New York Central (1965–1966), and 170 ordered post-merger (1968–1969); these were numbered in the 3000–3274 series and primarily handled freight on the dense Eastern network. Southern Pacific acquired 68 units from 1966 to 1967, numbered 6770–6837, deploying them in fast freight service across and the Southwest, often paired with SD40s for heavy tonnage. Other notable U.S. operators included the Baltimore & Ohio with 140 units (1966–1971, 3684–3779 and 4000–4064) for and merchandise trains, and the Illinois Central with 60 units (1966–1970, 3000–3059) focused on Midwestern freight routes. In Canada, Canadian National ordered 16 standard GP40s in 1967, numbered 4002–4017, for general freight on its transcontinental lines, with eight additional GP40TC variants (tonnage control-equipped, numbered 600–607) built in late 1966 for specialized hump yard operations at major facilities like MacMillan Yard. Mexican carriers received 18 standard GP40s total: (N de M) 10 units (8400–8409, 1967) and 8 units (1000–1007, 1971), for freight and yard service on their networks; these were adapted for metric-gauge operations. Deployment patterns across all operators emphasized the GP40's versatility in mixed freight consists, where its turbocharged power enabled sustained speeds on undulating terrain without frequent .
RailroadQuantityBuild YearsRoad Number RangesInitial Service Types
Southern Pacific681966–19676770–6837Road freight, general merchandise
300 (incl. inherited)1965–19693000–3274 (various)Road freight, hump yards
Baltimore & Ohio1401966–19713684–3779, 4000–4064Coal drags, merchandise
Illinois Central601966–19703000–3059Road freight
Canadian National1619674002–4017Road freight
1019678400–8409Freight, yard service
819711000–1007Freight, yard service

Rebuild Programs

During the mid-1980s through the , a surge in rebuild programs for aging EMD GP40 locomotives emerged, driven by the need to extend the operational life of these units amid rising maintenance costs and the desire for fleet modernization without the expense of entirely new purchases. Railroads and leasing companies pursued these initiatives to comply with emerging emissions standards, enhance , and improve overall reliability for continued service in freight and operations. This period saw increased focus on life-extension efforts as the original GP40s, built between 1965 and 1971, approached or exceeded 20-30 years of service, making outright replacement less economically viable given the robust design of the EMD 645-series prime mover. Common modifications in these programs included replacing or overhauling the 16-cylinder 645E3 engine with variants such as the 12-cylinder 645 or the fuel-efficient 16-645F3B, often derating output to 2,500-3,000 horsepower for better emissions control and lower operating costs. Upgrades frequently incorporated microprocessor-based control systems, such as EMD's EM2000 or Woodward governors, to optimize response and diagnostics; improved with enhanced resistor grids for better ; and the addition of (HEP) generators for passenger service compatibility. These changes prioritized reliability enhancements, reducing downtime and extending component life, while addressing regulatory pressures for cleaner operation without requiring full fleet turnover. Major rebuild efforts included Conrail's contributions through its CREX leasing arm in the , where former Penn Central GP40s were refurbished for continued freight use or sold for passenger conversions, such as those rebuilt by Morrison-Knudsen into GP40PH-2 units for Transit. In-house programs by the Atchison, Topeka and Santa Fe in the mid- focused on select units, like the derating and repainting of ex-Toledo, Peoria & Western GP40 1000 to ATSF 2964 for local and switching duties. The Burlington Northern conducted rebuilds in 1989, converting six ex-Chicago, Burlington & Quincy GP40s into GP40E models with updated electrical systems at its own shops. Helm Leasing emerged as a key player, converting dozens of GP40s into variants like the GP40-3 and GP40u starting in the late , often at third-party facilities like Boise Locomotive, emphasizing controls and emissions-compliant engines for lease to various operators. Across these and other initiatives, approximately 200-300 GP40s underwent significant rebuilds, transforming them into more versatile and efficient assets. Economically, these programs offered substantial savings, with rebuild costs typically ranging from $500,000 to $1 million per unit in dollars—often half or less than the $2-3 million price tag for a new four-axle EMD like the GP40-2—allowing railroads to allocate resources toward other infrastructure needs while maintaining fleet capacity. Specific variants such as the GP40N, GP40R, and GP22ECO represent specialized evolutions of these general rebuild efforts, tailored for commuter or eco-focused applications.

Rebuilds and Modernizations

GP40N

The GP40N is a rebuild variant of the EMD GP40 and GP40-2 diesel-electric locomotives, undertaken by the at its Jenks Locomotive Shop in . The program commenced in 2016 to extend the operational life of older units in the UP fleet, with the first GP40N—originally UP 9993, later renumbered UP 1337—completed in April of that year. These rebuilds focus on upgrading control and electrical systems while retaining the core mechanical components, enabling continued use in heavy freight service. A total of 129 units have been converted, drawn from UP's acquired fleet including former Southern Pacific, Western Pacific, and locomotives. Key modifications include the installation of the NEXSYS III-i microprocessor-based , which offers a compact design for enhanced reliability, improved adhesion control, and advanced throttle and options to optimize and performance. The original 16-cylinder EMD 645E3 prime mover is retained and derated slightly for longevity, producing 3,000 horsepower, paired with updated electrical systems such as new alternators and control wiring to reduce maintenance needs. Air brake systems receive 26L upgrades for better responsiveness and compliance with current (FRA) safety regulations. The standard cab from the donor units is preserved, providing crew comfort with improved visibility in some cases due to the extended hood configuration on select GP40-2 donors. These locomotives entered immediately following rebuild, primarily assigned to mid-distance freight assignments across UP's 32,000-mile network in the western and . Many units operate in helper service on grades like those in the Rockies or in yard and local duties, demonstrating the rebuild's success in cost-effective fleet renewal. As of 2025, the majority remain active, with some units featuring UP's standard gray and red livery and others retaining predecessor markings during transitional periods. Retirements have been minimal, underscoring the variant's durability in modern railroading. Unique to the GP40N is its integration of NEXSYS technology, originally developed for newer EMD models, adapted here to breathe new life into 50-year-old platforms while meeting FRA and standards without full structural overhauls. This approach contrasts with more extensive third-party rebuilds, emphasizing in-house efficiency and rapid return to service. Representative examples include UP 1341 (ex-SP 7135, rebuilt 2017) and UP 1487 (ex-SP 7125, rebuilt 2019), both exemplifying the variant's role in supporting UP's high-volume intermodal and bulk freight operations.

GP40R

The GP40R is a rebuild variant originally created by the Illinois Central Railroad (IC) in the 1980s from its own GP40 locomotives to enhance crew safety and meet regulatory standards. Following the 1998 merger with Canadian National (CN), several units were incorporated into the CN fleet, with some later transferred to other operators. Approximately 26 units were rebuilt by IC, featuring a full-width body design extending across the front of the locomotive for improved cab protection in collisions. Key features of the GP40R included a rebuilt 16-645E3 prime mover delivering 3,000 horsepower, a redesigned carbody with a high short hood for improved and protection, enhanced cooling systems for better thermal management, and MTU air filters to reduce intake contamination in harsh environments. The body was widened to support the broader cab structure while maintaining compatibility with standard track gauges. These modifications emphasized cold-weather reliability, with components selected for durability in sub-zero temperatures and heavy , making the variant well-suited for operations in northern networks. Renumbered into the 3100-series (ex-IC 3100-3125 series), the GP40R fleet entered service primarily for through-freight assignments, hauling bulk commodities and intermodal trains across and the U.S. until the early 2000s. As older power was phased out, several units were transferred to the for continued freight operations in the .

GP22ECO

The EMD GP22ECO represents a modern rebuild of GP40-series locomotives, introduced by (EMD, now under ) in 2009 to provide an emissions-compliant upgrade for aging fleets. This program targets core units from GP40 and similar models, repurposing them for continued service while addressing environmental regulations through comprehensive overhauls. Key features include replacement of the original 16-cylinder 645-series prime mover with an 8-cylinder EMD 710G3A-T2 ECO engine rated at 2,150 horsepower, which meets EPA Tier 2 emissions standards via electronic , aftercooling, and optimized combustion. Accompanying upgrades encompass the EM2000 , enhanced cooling, and improvements, resulting in approximately 25% lower fuel consumption and a 64% reduction in (NOx) emissions compared to unregulated pre-1973 locomotives. Some variants incorporate further modifications for Tier 4 compliance, achieving even greater emissions cuts. As of 2020, over 50 GP22ECO units have been completed, with notable series including Union Pacific's 2000-series low-emissions switchers deployed in yards. BNSF has also acquired units for hump yard operations. These rebuilds reflect ongoing demand driven by EPA mandates for emissions retrofits in switching service from 2020 onward. Primarily employed as yard switchers and light road power, the GP22ECO extends the operational life of donor units by 20–30 years, potentially into the 2040s, at a rebuild cost of $1.5–2 million per —offering substantial savings over new builds while reducing lifecycle fuel and maintenance expenses.

Preservation and Legacy

Preserved Units

Several EMD GP40 s have been preserved for static display or operational use, highlighting their role in mid-20th-century freight transportation across . As of 2025, at least two units remain preserved, often through efforts by railroad museums and heritage operations to maintain these 3,000-horsepower workhorses despite challenges like scarce parts for their 16-645E3 prime movers. One notable example is Baltimore and Ohio 3684, built in November 1966 (works no. 32644), which is operational at the Baltimore and Ohio Railroad Museum in , . Penn Central 3118 (built August 1968, works no. 34295), ex-Conrail and ex-DRGW, was purchased by the Austin Steam Train Association in 2024. The locomotive, now classified as a GP40-3 after upgrade, operates in Horizon Rail livery (numbered 3134) at , with plans for a Southern Pacific "Black Widow" paint scheme. Preservation efforts for GP40s often involve volunteer groups tackling issues like parts availability, with restorations relying on donor components from scrapped sisters or aftermarket suppliers to keep these 65-foot-long units functional or display-ready. These initiatives highlight the locomotive's lasting historical significance beyond active railroading.

Current and Former Operators

The EMD GP40 and its variants saw widespread use among major North American railroads following their initial deployment, with many operators transitioning them to secondary roles before eventual retirements. , which inherited a substantial fleet from predecessors like Penn Central and New York Central, utilized GP40s for freight service until the mid-1990s, retiring nearly all units by 1995 with only one exception preserved for special use. The Atchison, Topeka and Santa Fe Railway (later BNSF) phased out its original GP40s primarily in the late , with the last unrebuilt unit retired in 1989, though rebuilt versions persisted into the 2000s for yard and local service. Union Pacific acquired numerous GP40s through mergers, including from Southern Pacific and Rock Island, rebuilding many to GP40-2 and GP40N standards at its Jenks shop to extend service life for hump yard duties and locals. As of November 2025, over 200 GP40-based locomotives remain in active revenue service across , predominantly as rebuilds adapted for efficiency and emissions compliance. Union Pacific operates 129 GP40N units, rebuilt from former GP40 and GP40-2 donors with controls for improved and fuel economy, primarily in switching and short-haul assignments. BNSF maintains 66 units derived from GP40s, including 22 GP40M rebuilds, 2 GP40E conversions, and 42 GP38-2N units upgraded by , deployed on local freights and yard operations in the western U.S. Shortline and regional carriers, such as the & Railway with its GP40-2 No. 3043 and the Lake State Railway with GP40-3 Nos. 4303 and 4304, continue to employ these locomotives for versatile freight handling on lighter rail networks. Second-hand sales have sustained GP40 viability abroad, particularly in Mexico where Ferromex rosters about 27 GP40-2 units, acquired from predecessors like and rebuilt for mainline service. In Canada, Canadian National's retired GP40s, including GP40-2LW variants, have been resold to regional operators like the Huron Central Railway for continued use in resource-hauling operations. Retirements of original GP40s accelerated from the through the due to structural fatigue and the high costs of maintaining 50-year-old prime movers, further hastened by U.S. regulatory mandates for (PTC) implementation, which favored modernized or newer locomotives compatible with onboard signaling systems. Today, surviving units primarily serve in low-speed, non-mainline roles as switchers and locals, leveraging their robust 3,000-horsepower output for cost-effective operations where upgrades in rebuilds like the GP40N mitigate ongoing age-related challenges.

References

  1. https://www.thedieselshop.us/Data%20EMD%20GP40.HTML
  2. https://www.american-rails.com/30937.html
  3. https://www.american-rails.com/645.html
  4. https://trainiax.net/mephase-emdgp38-40.php
  5. https://rapidotrains.com/emd-gp40-masterclass
  6. https://utahrails.net/up/up-diesel-story-1934-1982.php
  7. https://vintagedieseldesign.com/2019/11/13/the-40-series-line-zenith-of-emd/
  8. https://www.sdrm.info/roster/diesel/emd/history/
  9. https://www.gatx.com/products/gp40/
  10. https://www.american-rails.com/gp40.html
  11. https://trainweb.us/emdloco/gp40.htm
  12. https://www.thedieselshop.us/Data%20EMD%20GP40P.HTML
  13. https://www.thedieselshop.us/Data%20EMD%20GP40TC.HTML
  14. https://www.trainorders.com/discussion/read.php?11,4865674
  15. http://rymalstation.blogspot.com/2022/02/cn-stuart-yard-gmd-gp40s.html
  16. http://www.trainweb.org/jaydeet/gp40.htm
  17. https://www.thedieselshop.us/NdeM.HTML
  18. https://railfan.com/why-buy-new-when-you-can-rebuild-again/
  19. https://www.alaskarails.org/pix/z-diesel-info/GP40.html
  20. https://conrailphotos.thecrhs.org/conrail-info/gp40-dispositions
  21. http://atsf.railfan.net/gp40/
  22. http://www.trainpix.com/bn/EMDRBLD/GP40E/INDEX.HTM
  23. https://www.thedieselshop.us/HELM.html
  24. https://forum.trains.com/t/cost-of-locomotives/55782
  25. https://www.trainorders.com/discussion/read.php?2,1698730
  26. https://www.thedieselshop.us/UP.HTML
  27. http://www.rrpicturearchives.net/locopicture.aspx?id=175074
  28. https://locomotive.fandom.com/wiki/EMD_GP40
  29. https://www.progressiverailroading.com/rail_industry_trends/news/EMD-delivers-first-two-repowered-locomotives-to-KCS--20706
  30. http://www.nsdash9.com/rosters/5900.html
  31. https://locomotive.fandom.com/wiki/EMD_GP22ECO
  32. https://www.up.com/aboutup/community/inside_track/low-emissions-loco-tech-211029.htm
  33. https://www.rrpicturearchives.net/locoList.aspx?mid=1167
  34. https://www.progressrail.com/en/Segments/Locomotive/Locomotives/RepoweredLocomotives.html
  35. https://web.archive.org/web/20240315231118/https://borail.pastperfectonline.com/webobject/FFB4A323-22E3-48DE-8239-491931155639
  36. http://crcyc.railfan.net/locos/emd/gpindex.html
  37. https://atlasrescueforum.proboards.com/thread/2879/looking-1980-diesel-mass-retirements
  38. https://dieselera.com/union-pacific-and-missouri-pacific-ex-rock-island-gp40s/
  39. https://www.up.com/aboutup/funstuff/locomotive-roster/index.htm
  40. https://www.thedieselshop.us/BNSF.HTML
  41. https://www.railpictures.net/viewphoto.php?id=780053&nseq=113308
  42. https://www.thedieselshop.us/LSRC.HTML
  43. https://www.thedieselshop.us/FXE.HTML
  44. https://www.rrpicturearchives.net/locolist.aspx?id=HCRY&mid=131
  45. https://www.facebook.com/nsdash9/posts/10157952572648843/
Add your contribution
Related Hubs
User Avatar
No comments yet.