|GMC - Old Look|
|GMC - Old Look|
|Years of manufacture||1940-1969|
|Length||various, see below|
The Old Look transit bus was introduced in 1940 by Yellow Coach beginning with the production of the model TG-3201 bus. Yellow Coach was an early bus builder that was partially owned by General Motors Corporation (GM) before being purchased outright in 1943 and folded into the GM Truck Division to form the GM Truck & Coach Division. The Yellow Coach badge gave way to the GM nameplate in 1944. Approximately 38,000 "old-look" buses were built during the 29-year production run. The 'Old Look' name is an unofficial term that was applied to this series of GM buses after the release of the GM New Look, this being an official term used by GM to describe their new line of buses.
Unlike most earlier buses, the GM 'Old Look' bus was built using a monocoque design, rather than a body-on-frame design, and it helped shepherd the change from gasoline to diesel-powered buses. Most 'Old Look' buses were powered with the Detroit Diesel 6-71 inline six-cylinder diesel engine, the exceptions being the shorter models that were powered by the four-cylinder version of the same diesel engine, and buses that were equipped with gasoline engines. Manual and automatic transmissions were available, with the Spicer angle-drive 2-speed transmission being used on automatic-equipped buses built prior to 1948. After 1948, the 2-speed Allison V-drive transmission was used on automatic-equipped buses. In 1940 and 1942, a small number of buses were built with electric propulsion systems instead of a transmission. The 'Old Look' was available in several lengths ranging from 25 to 41½ feet, though the most common models were 35 and 40 feet long. Most Old Look' buses were 96 inches wide, but 102-inch wide models were available beginning in 1948. In 1946 GM began offering its Thermo-matic heating and ventilation system, and in 1952 started making suburban models (buses with larger passenger windows, high-backed forward-facing seats, and optional luggage racks). Beginning in 1953, air-ride suspension became standard on all but the smallest model buses, and in 1958, air conditioning was added as an available option.
In 1959, GM introduced its New Look bus and production stopped on the majority of 'Old Look'. The 28-foot models were built until 1963 and the 30-foot models were built until 1969.
The model designations used for Old-look buses consisted of a series of two or three letters followed by a series of four numbers (for example, TDH-4512). The letters and numbers gave a basic description of the type of bus as follows:
- (T) denoting a transit bus
- (D) denoting a diesel engine,
- (G) denoting a gasoline engine.
- (H) denoting a hydraulic (automatic) transmission
- (M) denoting a manual transmission
- (E) denoting electric propulsion
First two numbers
- (##) first two numbers denoted the nominal seating capacity and length of the bus:
- (27) for 25-foot buses
- (31) or (32) for 28-foot buses
- (35) or (36) for 30-foot buses
- (40) for 33-foot buses
- (45) for 35-foot buses
- (48) for 37¾-foot buses
- (51) for 40-foot buses
- (54) or (55) for 41½-foot buses.
Last two numbers
- (##) last two numbers denoting the model number.