<P> The automatic transmission was invented in 1921 by Alfred Horner Munro of Regina , Saskatchewan , Canada , and patented under Canadian patent CA 235757 in 1923 . ( Munro obtained UK patent GB215669 215,669 for his invention in 1924 and US patent 1,613,525 on 4 January 1927 ) . Being a steam engineer , Munro designed his device to use compressed air rather than hydraulic fluid , and so it lacked power and never found commercial application . The first automatic transmission using hydraulic fluid may have been developed in 1932 by two Brazilian engineers , José Braz Araripe and Fernando Lehly Lemos ; subsequently the prototype and plans were sold to General Motors who introduced it in the 1940 Oldsmobile as the `` Hydra - Matic '' transmission . They were incorporated into GM - built tanks during World War II and , after the war , GM marketed them as being `` battle - tested . '' However , a Wall Street Journal article credits ZF Friedrichshafen with the invention , occurring shortly after World War I. ZF 's origins were in manufacturing gears for airship engines beginning in 1915 ; the company was founded by Ferdinand von Zeppelin . </P>
<P> The automatic transmission was invented in 1921 by Alfred Horner Munro of Regina , Saskatchewan , Canada , and patented under Canadian patent CA 235757 in 1923 . ( Munro obtained UK patent GB215669 215,669 for his invention in 1924 and US patent 1,613,525 on 4 January 1927 ) . Being a steam engineer , Munro designed his device to use compressed air rather than hydraulic fluid , and so it lacked power and never found commercial application . The first automatic transmission using hydraulic fluid may have been developed in 1932 by two Brazilian engineers , José Braz Araripe and Fernando Lehly Lemos ; subsequently the prototype and plans were sold to General Motors who introduced it in the 1940 Oldsmobile as the `` Hydra - Matic '' transmission . They were incorporated into GM - built tanks during World War II and , after the war , GM marketed them as being `` battle - tested . '' However , a Wall Street Journal article credits ZF Friedrichshafen with the invention , occurring shortly after World War I. ZF 's origins were in manufacturing gears for airship engines beginning in 1915 ; the company was founded by Ferdinand von Zeppelin . </P>
when did the first automatic transmission come out
when did the first automatic transmission come out
1921
1921