The first mass-produced fully-automatic transmission developed for passenger automobile use was the GM Hydramatic introduced in 1940.
Throughout the 1950s, all GM Marques continued developing automatic transmission designs, both jointly and independently.
Early models included: Introduced in 1964, Turbo-Hydramatic use quickly spread across all GM divisions, and they became referred to simply as Hydramatics (like GM's original automatic of totally different design), except for the Super Turbine 400 model.
By the 1970s, Turbo-Hydramatic variants had replaced all of GM's early automatic transmission designs.
Starting in the early 1980s, the Turbo-Hydramatic was gradually supplanted by four-speed automatics, some of which continue to use the "Hydramatic" trade name.