Those stamping numbers are: 3831704 – 1963 only. 3851325 – 1964-'65. 3885010 – 1965-'67. 3925660 – 1968-'70. ... Muncie also had a second close-ratio transmission coded M22 and known as the "rock crusher," which was used behind performance big-block engines and in some Corvettes. These M22 units are highly …

Take off the side cover and look at the angle of the gears. M-20, m-21 will have 45 degrees gears and the m-22 is 22.5 degrees. They used this to reduce friction …

There's a long number right beside the P9B25A number, but I can't make out the first two or three letters. When I count over right to left to where the "N" should be for the VIN# it looks more like a number, so I'm wondering if it's something other than the VIN#. Anyone with a M-20 or maybe even a M-21 should have numbers located in the …

M22 4 speed rock crusher. Jump to Latest ... Beyond just restorers, flippers and number matchers, ALOT of people are into this hobby for the fun and giggles of driving what we consider felt just right back in the 60s and 70s. The whine, banging a 4 speed, full throttle, how the Hurst shifter feel rowing through the gears. ...

Step 2. Count the input shaft teeth to find out the make of the transmission. Input shafts differ in each GM transmission, so you can easily identify an M-22 "Rock Crusher by its input shaft count. Each transmission has different numbers of teeth. An M-22 "Rock …

The famous "rockcrusher" M22 4 speed had the same gear ratios as the M21 but with a heavy duty gearset. Although the gears are not spur gears ( completely straight ) they still produced a fair amount of gear noise thus the "Rockcrusher" name.

Times and requirements have changed making both the M21 and M22 the closest ratio production 4 speeds ever produced but also not practical for today's driving habits unless road racing is your thing. The new Muncies …

The M22 "Rock Crusher" followed four years later. It uses stronger components to handle big-block power. The original M20 was only offered for one year. It has the GM casting number "3831704" on the case. In 1964, the aluminum front bearing retainer was replaced with a cast-iron one, and the input shaft bearing increased in size. This ...

Is there anyone out there that and tell me the difference between a Muncie M22W and a M22 Rock Crusher. I have tired to look online but not finding anything to help. I would appreciate it. Thanks. ... The last 3 numbers of the casting number on the main case were milled off and 3 new numbers were STAMPED in the place of the removed …

Complete original GM Muncie transmission rebuilt and guaranteed for 1 year. Correct fit for all 1969 - 1973 model Chevelles and Novas. This one will have the holes on the side where a bolt will secure your shifter linkage levers. This is …

The M22 transmission has a 20 degree helix angle on the gear set as opposed to a 45 degree angle found on the M20 and M21 and were made with a higher nickel alloy. The straighter angle was designed to produce …

The M22 Rock Crusher used a gearset that features less of an angled-tooth gearing (right). Images courtesy chevelles.com. The gear ratio of the Chevy four-speed transmission placed in any car was usually …

M22 Rock Crusher. Jump to Latest ... The numbers you are looking for are stamped into the passenger side of the main case, towards the rear of the front case (actually the middle of the trans) But this will only tell you what the trans was originally, like drptop says, ya gotta pull the side cover off to be sure. One good indicator ...

Identifying Muncie 4- Speeds. Several things are needed to identify a Muncie correctly. The first is a main case casting number. Second a count of the input shaft and output shaft splines and if any rings or grooves exist around the input shaft splines. Third are date codes and VIN numbers that help confirm that the above case and gears belong together.

Reading Serial and VIN Numbers Serial numbers for Muncie 4 speeds always begin with the letter "P". P stands for Muncie Plant. ... Letter: C M22 Ratio. Muncie 4 Speeds. ... thus the nickname "rock crusher". The higher nickel alloy allowed for more impact of the gears. Another misconception is if you have a drain plug you have an M22.

The early production Muncie four-speed case is the small-bore unit and can be identified by the GM casting number 3831704 (see Muncie M20/M21/M22 Main …

Ultra rare Factory M-22 "Rock Crusher" 4 Speed! (yes, it is really an M-22 car, one of very, very few built in 1968) NUMBERS MATCHING ORIGINAL FACTORY ENGINE AND DRIVETRAIN. Special ordered when new with a 3.07:1 Posi-traction rear! ... and highest quality L78/M22 Camaros on earth this is your chance! Serious buyers please contact …

The Muncie M22 is known as the Rock Crusher. See how we improve its strength and versatility by adding a Gear Vendors Overdrive. Cam Benty Writer John McGann Photographer Nov 04, 2022.

The M22W set manufactured by Autogear was designed to be a better alternative to the M22 since most do not like the 2.20 1st gear ratio of the M22. It also has a better ratio spread then a conventional M20. It maintains the M22 gear helix angles. BE CAREFUL! There are people selling M22W sets made in Taiwan that duplicate the exact …

1967 -74 Production codes will start with a P followed by a number for the year, a letter for the month, and two numbers for the day. For example P7C05 will read: Muncie four speed aluminum for passenger car 1976, March, 5th. ... A = 2.52 1st gear wide ratio M20, B=2.20 1st gear close ratio M21, C = 2.20 first gear Rock Crusher M22. One example ...

Rebuilt Transmission M22 1966-1974 Rock Crusher MTGM038. Rebuilt Overhaul Bearing Kits M21 & M22 Transmission. Kits w/OE Style Bearings. Drawing Image Description Part Number N.I. M20 (63-65) (72mm OD Input Bearing) TRSBK117A N.I. M20 (63-65) (80mm OD Input ...

Just added NEW GM OE style cases casting number (3925660) 1968-70 1" style. From $414.27 . ... In 1965, GM introduced an even more robust version of the Muncie transmission, known as the M22 or "Rock Crusher." This transmission, with its distinctive whine, became synonymous with high-performance cars of the era. The M22 featured …

C3 General - M22 Rock Crusher - Just bought a 1968 (originally was 427/435..currently has a CE replacement block from 69)) and I believe it has a M22 vice M21. Intent at some point in the near future is to crawl under and check numbers/code. I know it has the factory 411 rear end (Code FB) so that is the first reason...

Input shafts differ in each GM transmission, so you can easily identify an M-22 "Rock Crusher by its input shaft count. Each transmission has different numbers of teeth. An M-22 "Rock Crusher" always has 26 teeth. Count …

The M22 Rock Crusher used a gearset that features less of an angled-tooth gearing (right). Images courtesy chevelles.com. The gear ratio of the Chevy four-speed transmission placed in any car was usually …

Although some claim that the M23 is a 'rock crusher', it is indicated that this box was assembled in both wide and close ratio components and also with straight cut gears common to the rock crusher (M22) transmission. Looks like you have a second design-feb. 28th, 1968, M20 or M21. Definitely not a rock crusher(no straight cut gears).

Although some claim that the M23 is a 'rock crusher', it is indicated that this box was assembled in both wide and close ratio components and also with straight cut gears common to the rock crusher (M22) transmission. This chart, so far, has been very accurate in identifying the muncie trans. over the years, so I wanted to share.

The Muncie M22 (Rock Crusher) 4-speed manual and the 3-speed Turbo Hydramantic 400. A heavy-duty 12-bolt axle was standard with the buyer's choice of 3.31 or 4.10 gears. ... real-world figures put the LS6 number closer to 500, matching the massive torque curve. Something that left a big impression on drivers of the day.

There also was a second, heavy-duty close-ratio version: the "Rock Crusher" (M22) that was offered on some of the high-performance big-block models, starting with the 1965 Corvette.

the motor was decked when rebuilt but still retains its original partial vin stamp at oil boss there is a picture in the lisiting. it also retains its numbers matching muncie m22 rock crusher 4-speed transmission and its original 12 bolt posi rear-end with factory 4.10 gears.