Ford B series

The Ford B series is a bus chassis that was manufactured by Ford Motor Company from 1948 to 1998. A variant of the medium-duty Ford F-Series, the B-series was developed for bus use. Alongside its sales in the United States and Canada, the chassis was exported worldwide for various manufacturers.

In contrast to the F-Series chassis-cab truck, the B-Series was a cowled-chassis vehicle: a bare chassis aft of the firewall, with all other bodywork supplied from a second-stage manufacturer. While primarily adopted for yellow school bus applications, the B series also saw various specialty uses.

Coinciding with the late 1996 sale of the Louisville/AeroMax heavy-truck line to Freightliner (which led to the introduction of Sterling Trucks), Ford ended cowled-chassis vehicle production after 1998. Though Ford has remained in the medium-duty segment (introducing the F-650/F-750 Super Duty for 2000), the company has not since developed a cowled-chassis derivative of the model line, instead concentrating on cutaway chassis vehicles. The role and market share of the B-series in the cowled-chassis segment was largely superseded by the Freightliner FS-65 and the Blue Bird Vision (a proprietary chassis paired with a body from its manufacturer).

For 1948, Ford released the F-series truck line, moving all truck production to a dedicated model family. The B series (B= Bus) was introduced as a cowled-chassis variant of the medium-duty F-5 and F-6 (1 ½ and 2-ton), slotted between pickup trucks and "Big Job" heavy conventionals.

For 1953, the second generation F-Series shifted to a three-digit model nomenclature (which remains in use by Ford today), with the B-series following suit. In 1968, Ford introduced diesel-fuel engines as an option, denoting such vehicles with a four-digit model number (this nomenclature ended for 1991).

Prior to 1969, Ford of Canada marketed the B-Series through both Ford and its Lincoln-Mercury dealer networks, with the latter selling it as part of the Mercury M-series truck line. At the time, rural Canadian communities had access to either a Ford or a Lincoln-Mercury dealership, but not both concurrently.

For its entire 50-year production run, the B-series paralleled the medium-duty F series in its development. Until 1966, medium-duty F-Series trucks differed from their lighter-duty counterparts primarily in their frame and front suspension design, retaining front bodywork commonality. For 1967, Ford medium-duty trucks were given wider front axles and their own front bodywork, with the B-Series using this design entirely. For 1980, a final generation was produced (undergoing a model revision in 1995).

For 1948, as Ford introduced the Ford F-series as its first dedicated truck platform, the B-series made its debut. Based on the medium-duty F-5 and F-6 (1½ and 2-ton), the B series was slotted between the pickup trucks and the "Big Job" conventionals. In 1951, the grille trim was redesigned, with the horizontal grille bars replaced by wider-spread vertical ones.