The GM Hydra-Matic was a success and installed in the majority of GM models by 1950. Through the 1950s, all makers were working on their own automatic transmission, with four more developed inside GM alone. All of GM's early automatic transmissions were replaced by variants of the
Turbo-Hydramatic by the 1970s.
1940–1967
Hydra-Matic —
Oldsmobile (now the trade name for all GM automatic transmissions)
1956-1964 4 speed Controlled coupling HydraMatic, also known as Cadillac 315 or P 315 HydraMatic, Oldsmobile Jetaway, Pontiac Super HydraMatic.
TempestTorque, ( Pontiac) a two speed based on Powerglide, but having the added feature of " Split Torque " dividing the engine power between mechanical connection and the torque converter in high gear.
The next-generation transmissions, introduced in the early 1990s, were the electronic
Hydra-Matics based on the
Turbo-Hydramatic design. Most early electronic transmissions use the "-E" designator to differentiate them from their non-electronic cousins, but this has been dropped on transmissions with no mechanical version like the new
GM 6L transmission.
Today, GM uses a simple naming scheme for their transmissions, with the "Hydra-Matic" name used on most automatics across all divisions.
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ab*This transmission is part of a joint-venture between
General Motors and
Ford Motor Company to split development of two transmissions, a longitudinal 10-speed and transverse 9-speed. Ford led the design of the 10-speed transmission, as well as filing the design patents for said transmission. According to an official report by the
SAE (Society of Automotive Engineers) the design of the 10-speed gearbox is essentially all Ford, while GM was responsible for designing the 9-speed 9T transverse automatic gearbox. As part of their joint-venture, Ford will let GM use the 10-speed transmission with rights to modify and manufacture it for their own applications. In-exchange for Ford's 10-speed transmission, General Motors will let Ford use its 9-speed transmission for front-wheel drive applications; Ford ultimately declined use of the 9T and instead, removed 1 gear and used the 9T as an 8-speed transmission.[2][3][4]
Muncie M20 — 4-speed longitudinal wide ratio manual transmission made by GM at their Muncie, Indiana factory
Muncie M21 — 4-speed longitudinal close ratio manual transmission made by GM at their Muncie, Indiana factory
Muncie M22 — 4-speed longitudinal heavy duty close ratio manual transmission made by GM at their Muncie, Indiana factory
Saginaw M26/27 transmission — 3 and 4-speed longitudinal light duty (less than 300 hp) wide ratio manual transmission made by GM at their Saginaw, Michigan factory
Muncie M62/M64 — 3-speed longitudinal transmission made by GM
Muncie SM420 transmission — 4-speed manual used up to 1967, very similar to sm 465 except small changes to gear ratios and location of reverse.
New Process Gear NP435 - 4-speed longitudinal transmission used in a select handful of 67-72 GM pickups
New Process Gear A833 RPO MY6 or MM7 — 4-speed longitudinal A833 overdrive transmission made by New Process Gear for early to mid 1980s General Motors Light Trucks
Muncie SM465 — 4-speed longitudinal manual used in 68- 91 Chevy 1/2 3/4 and 1 ton trucks
Borg-Warner R-11 overdrive - 3-speed manual transmission with electric overdrive Ford used them up until 1975 in trucks.
Borg-Warner T-50 transmission — 5-speed longitudinal manual - used by GM in its RWD H-Body cars and a few other limited light duty applications from 1976 to 1978;