Following the war, Allison converted his company to peacetime activities. Annoyed to discover a lackluster main engine after a personal yacht purchase, he began the design and production of his own unit. His precision-produced marine mill included a steel-backed bronze crankshaft and connecting rod bearings.
Aircraft-component development also began. the company adapted Rolls-Royce high-speed reduction gear technology to Army and navy Liberty powerplants. these close-tolerance aircraft gearboxes drove the company's component machining leadership. Roots-type superchargers were also added to the production mix. the company changed its name to the Allison Experimental Co., which General Motors acquired a year after James Allison's death from pneumonia in 1928.
General Motors Purchases Allison
Dubbed Allison Division of General Motors in 1934, the company began work on the famed V-1710 12-cylinder, 750hp, liquidcooled aircraft engine. this massive mill first saw service in the Army's Curtis P-40 tomahawk. Improved versions later found in the P-51 and P-38 fighter aircraft developed 1,000 hp. After the War, these surplus mills were utilized in hydroplane boat racing, sled pulling, and Bonneville speed runs.
The First Allison Automatic Transmission
In the early '40s, the Allison division officially entered the transmission business with the development of the CD-850 tank transmission. Although broader transmission operations began in 1946, the company's trendsetter, CD-850, officially launched the division's family of off-highway transmission products. Then transmission V-drive units were introduced in 1947. the V-drive transmission made the development of the torque converter necessary, and the new torque-converterequipped transmissions were aimed directly at the transit industry. the automatic- transmission concept freed drivers from gearbox hassles, allowing the automatic transmission to do the work.
M551 And M109 Military Vehicles
Allison specialized in transmission products in a variety of established and profitable fields. In the '60s, the company broadened its activities with the production of complete military-vehicle platforms. Ammunition production was also added. the company initiated the design, development, and production of the Army's M551 and M109 armored vehicles, and 81mm shells were also added to the production agenda.
On the transmission side, Allison had accomplished a great deal in a short quarter century. Among the quiet development firsts: the first powershift marine gears, a powershift unit for highway trucks, the crossdrive unit for tracked vehicles, hydraulic retarders, a fully automatic truck transmission, a twin-turbine transmission, and a variable-input power torque converter for material-handling equipment.
Allison's transmission offerings covered a wide spectrum in the '70s. After all, Allison had the resources and the engineering expertise working in-house with other specialized GM divisions. Euclid OTR, EMDLocomotives, and Detroit Diesel all worked in conjunction with Allison on civilian and military projects.
Detroit Diesel And Allison
Allison entered the '80s with a mixed agenda, along with several uncertain marketing approaches. to begin with, several name combinations quietly appeared in the GM literature. Detroit Diesel and Allison teamed up to form Detroit Diesel Allison (DDA), only to be split into separate entities again in 1987 when Allison transmission appeared.