Automatic transmission
type of motor vehicle transmission that automatically changes gear ratio as the vehicle moves
An automatic transmission (AT) or automatic gearbox is a multi-speed transmission used in motor vehicles.
The 1904 Sturtevant "horseless carriage gearbox" is often considered to be the first true automatic transmission. The first mass-produced automatic transmission was General Motors' Hydra-Matic, introduced in Oldsmobile models for the 1940 model year.
Automatic transmissions are especially prevalent in vehicular drivetrains, particularly those subject to intense mechanical acceleration and frequent idle/transient operating conditions; commonly commercial/passenger/utility vehicles, such as buses and waste collection vehicles.
Prevalence
Vehicles with internal combustion engines, unlike electric vehicles, require the engine to operate in a narrow range of rates of rotation, requiring a gearbox, operated manually or automatically, to drive the wheels over a wide range of speeds.
Globally, 43% of new cars produced in 2015 were manual transmissions, falling to 37% by 2020. Automatic transmissions have long been prevalent in the United States, but only started to become common in Europe much later. In Europe in 1997, only 10–12% of cars had automatic transmissions.
In 1957 over 80% of new cars in the United States had automatic transmissions. Automatic transmissions have been standard in large cars since at least 1974.
Begin with the source’s own compact description: “Automatic transmission” is type of motor vehicle transmission that automatically changes gear ratio as the vehicle moves. The dossier treats that line as a proposition to test through Automatic, transmission and type, not as a finished interpretation.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 23, 2026. The linked authority identifier is Q843592. The Library of Congress control number is sh85010407. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1904, 1940, 2015 and 2020.
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This entry incorporates text from “Automatic transmission” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.