History of Transmission in Motor Cars / Automobiles

6.14 Transmission

• See Part 1. The Early History, Section 10.3 (Transmission).

• In 1928 Cadillac/GM introduced a fully-synchronized manual transmission system called Syncro-Mesh.
  
  

• In 1932 Cadillac/GM began working on a shiftless transmission system. By 1934 they had developed a step-ratio gearbox that would shift automatically under full torque.
  
  

• By 1937 they had produced a semi-automatic transmission system called Automatic Safety Transmission (AST). It was fitted to Oldsmobile models from 1937 to 1939.
  
  

• In 1939 GM introduced an automatic transmission system called Hydra-Matic Drive. It was first installed in a 1940 Oldsmobile model