This is a Very Rare and Completely Original M-22 Transmission with REAL GM Rock Crusher Gears for a 1970 70 1971 71 and 1972 72 GM Vehicles including, Chevy, Corvette, Camaro Z28, Pontiac Firebird and Chevelle M22, (M-22), Muncie Close Ratio Rock Crusher 4 Speed Transmission. 1972 VIN includes (?C12 50429 37660?).
Very Rare Part Tag code still on transmission (6271517WJ) cross references to 1971 and or 1972 Camaro and Firebird.
These first came out in the 1970 Chevelle with the fine spline input and they were then released in the 1971 and 1972 Corvettes and other GM Cars.
This has the fine spline input with no lines or grooves, the special GM original factory gears, (no aftermarket or imported gears), and the fine spline large output shaft. The 1970 Chevelle and 1971 and newer other cars use this fine 26 spline input. This transmission comes with a drain plug from the factory, like all M-22 transmissions.
The gears are straighter cut than the normal Muncie 4 speeds, so they make more whining noises and that is why the are called "Rock Crusher" transmissions. This is the only one we have left after owning many of them over the years. We used to use them in our SCCA and IMSA Road Racing Corvettes back in the mid to late 70's. We actually qualified in the fifth starting position in one of our old beater wide body Corvettes at the 1977 Sebring 12 Hour Race in Florida, which is still hard to believe to this day! I actually rebuilt the stock leaking Corvette brakes and the Rock Crusher Transmission between qualifying and the start of the race, believe it or not! We couldn't afford the Wilwood Brakes that our competitors had on their cars. But enough about that, this is the 2.20 first gear setup like all real M-22 transmissions. None of them were built as wide ratio transmissions. This deserves to be in a very special car!
Main Case: 3925661 Stamped P2C15C, March 15, 1972 Rock Crusher
Side Cover: 3952648 with Bolt-on Type Shift Shafts and 3-4th gear TCS switch which has been capped off.
Tailhousing: 3978764 with Right Hand, (Passenger Side), Speedo Gear Set
Original GM M-22 Rock Crusher Gear Set with No Rings on Input "Keep Your GM Car All GM!"
|Corvette Series:||Not Corvette|
|Part Brand:||GM, General Motors|
|GM Group Number:||4.000|
|Manufacturer Part #:||Various|
|Interchange Part #:||3925661|
|Placement Details:||M-22 Transmission Behind the engine assembly|
|Manufactured In:||United States|
|Shipping Price:||$116.00 (Continental US)|
Very Rare Completely Original Good Used 1970 70 1971 71 1972 72 GM Chevy Corvette Camaro Chevelle M22 M-22 Muncie Close Ratio Rock Crusher 4 Speed Transmission Chevy Chevrolet C1 C2 C3 C4 C5 C6 Corvette NCRS Top Flight Bloomington Gold Tracy Performance Corvette Parts Roseville Detroit Michigan 48066 Sting Ray 283 302 327 348 350 396 402 409 427 454 502 Engine Transmission