What was the first car to have a true automatic transmission?

The 1948 Oldsmobile was the first model to use a true automatic transmission. The introduction of the automatic transmission offered “no-muss, no-fuss” form of shifting.

The earliest automobiles offered only manual transmissions, which were similar in principle to stick-shift vehicles of the 21st century. These cars sported two forward gears and one reverse, coupled to the engine via a series of pedals. But as cars grew larger and traffic got worse, engineers began searching for a way to have the car automatically shift from one gear to another. Designers spent many decades perfecting the modern automatic transmission.

The first automatic transmission was invented in 1921 by a Canadian steam engineer, Alfred Horner Munro. Munro designed his device to use compressed air rather than hydraulic fluid so it lacked power and never became sold commercially. General Motors then developed the first automatic transmission using hydraulic fluid in the 1930’s; it introduced the “Hydra-Matic” transmission in 1940.

The 1948 Oldsmobile used the Hydra-Matic transmission. This transmission, developed by GM engineer, Earl Thompson, was advertised as: “The greatest advance since the self-starter”. The Hydra-Matic went through continual upgrading and refinements through 1955; its basic design and theory were used consistently for a remarkably long time. In 1956, the Hydra-Matic was replaced with the Jetaway. The “Jet” was not great; it quickly gave way to the Turbo Hydra-Matic in 1969.