Wikipedia
The Hy-Drive was a Chrysler Corporation transmission introduced in August 1940 in Chryslers and DeSotos, Dodges in 1949, and Plymouths in 1953. It was a hybrid manual transmission with a torque converter like an automatic. Although Hy-Drive cars had a clutch pedal like a traditional manual transmission, it was only used put the car in gear. Once underway, the driver could upshift and downshift using the gear shift without using the clutch or even lifting off the accelerator.
The industry was caught by surprise by the advent of the automatic transmission in the late 1940s. General Motors' Dynaflow, introduced by Buick in 1948, was a smash hit with the public, very soon being fitted in over 80% of new Buicks. (GM's fully automatic Hydramatic, which debuted in 1939, was in 70% of Pontiacs that year.) Chrysler had previously offered a Fluid Drive fluid coupling (not a torque converter, as it did not multiply the torque) on their manual transmissions, and the Hy-Drive was an evolution of this. It was sold by Plymouth until the fully automatic PowerFlite was available in 1955. About 75,000 cars came equipped with this transmission.