Chevy Transmissions: Muncie 4 Speed M22 Rockcrusher ...
Chevy Transmissions: Muncie M22 "Rock Crusher 4 Speeds were made From 1965 TO 1974: The most popular transmission of it's time for high performance cars built for Chevrolet and all performance oriented cars. They have the same gear ratios as the legendary M21 but with a heavy duty gearset.