Czechman, the 1939 Olds Hydramatic had a clutch. It was used for starting and stopping, but the shifts were automatic. By 1940, GM had figured out how to incorporate a fluid coupling that allowed the engine to idle in gear.
The Dodge "Gyro-Matic" and the Chrysler "M-6" transmission was an electrically-shifted 4-speed, with 2 speeds in Low range, and 2 speeds in High. It was clutched to engage either low or high, and the next ratio was selected electrically by releasing the throttle back to idle. It could be shifted 1-2-4, or 1-3-4, depending on when the low/high manual shift was made. I found I could let my 1951 Chrysler do the 1-2 shift, manually shift to high range, and hit the electric kickdown switch by going to full throttle, and make it use all 4 gears. I'm amazed that old flathead 6 survived as long as it did!
Jerry
