Muncie M-21 4 Speed Transmission 3885010 Chevy Buick Pontiac Olds Close Ratio GM

General Motors Part No: Chevy Chevrolet Buick Olds Oldsmobile Pontiac four Manual gear, 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967, 1968 1969 1970 1971 1972 1973 1974 Wide Ratio M20 M-20 hurst Z/28, Z28 RS SS shifter hot rat rod traditional nhra scta trog drag, race muscle car SBC BBC Small Big Block 265 283 327 302 350 400, 396 427 454 326 400 428 455 430 389 401 425 nailhead tri power, camaro chevelle nova impala corvette cutlass 442 vista cruiser, skylark gs firebird tempest lemans gto grand gran prix gp, monte carlo el camino console am fm radio multiplex stereo, yenko copo tach tachometer l88 l-88 day 2 two vgate v gate verti, vertical ram rod competition plus bucket seats tach tachometer, m20 m21 m22 m 20 21 22 rockcrusher rock crusher 660 5660 case

Manufacturer: General Motors

Part Number: Chevy Chevrolet Buick Olds Oldsmobile Pontiac four Manual gear, 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967, 1968 1969 1970 1971 1972 1973 1974 Wide Ratio M20 M-20 hurst Z/28, Z28 RS SS shifter hot rat rod traditional nhra scta trog drag, race muscle car SBC BBC Small Big Block 265 283 327 302 350 400, 396 427 454 326 400 428 455 430 389 401 425 nailhead tri power, camaro chevelle nova impala corvette cutlass 442 vista cruiser, skylark gs firebird tempest lemans gto grand gran prix gp, monte carlo el camino console am fm radio multiplex stereo, yenko copo tach tachometer l88 l-88 day 2 two vgate v gate verti, vertical ram rod competition plus bucket seats tach tachometer, m20 m21 m22 m 20 21 22 rockcrusher rock crusher 660 5660 case

Interchange Part Number: Chevy Chevrolet Buick Olds Oldsmobile Pontiac four Manual gear, 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967, 1968 1969 1970 1971 1972 1973 1974 Wide Ratio M20 M-20 hurst Z/28, Z28 RS SS shifter hot rat rod traditional nhra scta trog drag, race muscle car SBC BBC Small Big Block 265 283 327 302 350 400, 396 427 454 326 400 428 455 430 389 401 425 nailhead tri power, camaro chevelle nova impala corvette cutlass 442 vista cruiser, skylark gs firebird tempest lemans gto grand gran prix gp, monte carlo el camino console am fm radio multiplex stereo, yenko copo tach tachometer l88 l-88 day 2 two vgate v gate verti, vertical ram rod competition plus bucket seats tach tachometer, m20 m21 m22 m 20 21 22 rockcrusher rock crusher 660 5660 case

This is an original 1967 Muncie 4 Speed M21 close ratio transmission.  These transmissions have a stellar reputation due to their tried and true performance and ease of use. The M-21 close ratio transmission has a 2.20 first gear. This transmission has the ratios between each gear closer for high performance use. If you have a 3.73 or numerically higher rearend gear, the M-21 close ratio transmission is a solid choice. These close ratio transmissions were farily rare when new and are very hard to find today.

This M-21 transmission looks to be in good original core condition. It was recently purchased from the estate of a long time hot rodder. All gears look very nice with no chipped teeth, pitting, etc.   I see no repairs, or modifications to this transmission. All 4 mounting ears are very nice.All threads are nice with no helicoils or thread inserts. The transmission spins through all 4 forward gears and reverse. The cluster gear has a good amount of play from the front to rear that will need to be looked at. I imagine there is a bushing missing or something. The forward slider moves freely like the locks have been removed or are not working properly  This is simply a very nice original M-21 transmission that should be rebuilt before use.

The casting number on the main case of this transmission is 3885010 as shown. The 3885010 case was used in the 1966 and 1967 model years. The assembly stamp reads P0824 which decodes as August 24th, 1966. The partial VIN of the car it was original installed in is stamped on the top of the maincase and reads "6Z101108" as shown. The tail housing has the casting number 3846429. The side cover is casting number 3831707 and the front bearing retaining carries the number 3851326 as shown. The case is bare aluminum and is free of paints and coatings with some a scatter grease/grime. This trans looks as sweet as cherry pie.

Below is a video of this transmission being shifted and spun through each gear. To watch the video on a desktop or laptop, simply click on the play icon in the photo below. To watch on a smart phone or tablet, copy and paste the link below the picture into your browser.

This is your chance to own a very hard to find Muncie M21 close ratio 4 speed transmission for your special car or collection at a GREAT PRICE! Don't Miss Out!

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