You're probably thinking about the Chevy passenger cars in 1950 that came with the Powerglide transmission and a splash-oiler 235. Basically, they used the medium-duty truck engine in a car, and added hydraulic valve lifters.
The first 2-door hardtop Chevy Bel Air that came to Nashville in 1950 was due to go on display in the showroom of Jim Reed Chevrolet on a particular date- - - -235 engine, Powerglide, and all. About midnight before the big rollout, four salesmen managed to hand grenade the transmission when one of them pulled the shifter into Reverse at about 80 MPH. The car got towed back to the dealership and went on display as scheduled, with about a foot of newspaper under the transmission to soak up the drips!
Jim Reed fired all the guys who were on that joyride!
Jerry