Most transmissions in modern automobiles use synchromesh to synchronise the speeds of the enter and output shafts. Having said that, just before the 1950s, most automobiles utilized non-synchronous transmissions. It was initially launched in 1939 for cars. It is made up of the fluid coupling and three planetary gears. https://gearbox53085.blogvivi.com/34405274/top-gearbox-secrets