People think all Muncie four-speeds are Rock Crushers, but they're not. They take on a duller chrome appearance, similar to something they'd use in the manufacturing of chrome. If you walk away from the job for long periods, cover all parts on the bench with clean, clear plastic sheets. West works chiefly by mail order. He can bore the cluster pin and put in a one-inch pin.
On the right, a reverse gear before being cleaned up. A lot of people call him looking for a correct transmission. An M22 retains less heat due to its straight-cut gears and the lack of thrust that helical-cut gears create. The synthetics leak out of them more easily than natural gear lubes. Upper row from left starts with three different shift shafts used over the years. He rebuilds them using all new gears and internal components.
Identification begins by visually identifying the units as Saginaw, Muncie or Borg Warner models and then by differentiating the three Muncie units visually and by decoding the serial number. Keep all parts and your hands free of dirt and even dust. Having the proper geometry is a necessity. The speed gears are independent of the main shaft. Next to it is a regular and less expensive brass synchronizer ring. Bottom left is an improved purged brass synchro ring.
The lever is engine power. The splines are on the shaft going into the engine and the input gear goes into the transmission. The top row shows a synchro ring on left and a cleaned up reverse gear on the right. Each shifter is specific to its application. The cluster is mated to all the speed gears, first, second third and fourth. West doesn't get involved in manufacturing parts.
Grit that gets into the grease in the shifter mechanism can cause real problems. Identify Muncie 1963 to 1967 transmissions. The 1986 pickup truck versions utilize a hydraulic clutch release, replacing a mechanical linkage in older versions. A later style cover with the clevis pin in the middle. Unsourced material may be challenged and. A serial number is stamped on all Muncie transmission cases. West will build it for him or her.
This can be important, especially on the top side, when the gearshift has to clear a console, a custom dashboard, a bench seat or even too hard a shifter boot. The status marker was used at the Muncie, Ind. Muncie transmissions are known for both high-performance and heavy-duty applications, with three different variations available: the M20, M21 and M22. These Muncies have the same serial number format, minus the gear ratio designation, so a spline and gear tooth count must be done. Saginaw and Borg Warner models are normally used on general purpose applications. The Muncie M20 is basically a wide-ratio transmission and was intended for normal street driving use. With a close-ratio box a driver can run through the gears and keep the engine in its power band so it performs in street racing or drag racing.
The 1988-91 versions have an aluminum top with improved shift feel. Much of the West's transmission work involves guys wanting something specific for their car. The M22 is called the Rock Crusher. The serial number provides the date of manufacture, however, on 1969 and later transmissions there is a letter code at the end which identifies the gear-ratio, which is different on all three Muncie models. Due to the values of these cars, the owners usually want an original appearance. According to West, synthetic oils shouldn't be used in Muncie four-speed transmissions, no matter what type of car they are in. Three synchro rings are stacked vertically.
The later 1966-1974 units had a 2. There have been three different output shafts for pickup trucks. You can pretty much get what you want. It will rattle at low rpms and whine at high rpms. Nowadays there are custom gear ratios and set ups, including M21 wide-ratio and M22 wide-ratio units. I enjoy what I am doing. The Muncie M21 is a close-ratio unit originally designed to be matched with 4.