User:Tuor~enwiki/Sandbox/Evolution of the Automatic Transmission

The automatic transmission began at the turn of the century, shortly after the automobile became a tool and not just a plaything of the rich and eccentric. It is credited for the spread of the automobile in America.

Planetary Manuals
The Ford Model T had essentially a clutchless manual.

First Full automatics
Oldsmobile's 1940 models featured Hydra-Matic drive, the first mass-production fully automatic transmissions. Initially an Olds exclusive, Hydra-Matic had a fluid coupling (not a torque converter) and three planetary gearsets providing four speeds plus reverse. Hydra-Matic was subsequently adopted by Cadillac and Pontiac, and was sold to various other automakers, including Bentley, Hudson, Kaiser, Nash, and Rolls-Royce. From 1950 to 1954 Lincoln cars were also available with GM Hydra-Matic. Mercedes-Benz subsequently devised a four-speed fluid coupling transmission that was similar in principle to Hydra-Matic, but did not share the same design.

The first torque converter automatic, Buick's Dynaflow, was introduced for the 1948 model year. It was followed by Chevrolet's Powerglide and Packard's Ultramatic for the 1950 model year. Each of these transmissions had only two forward speeds, relying on the torque converter for additional gear reduction.

In the early 1950s Borg-Warner developed a series of three-speed torque converter automatics for Ford Motor Company, Studebaker, and several foreign and independent makes.

Chrysler was late in developing its own true automatic, introducing the two-speed torque converter PowerFlite in 1953 and the three-speed TorqueFlite in 1956.