These surface from time to time but are rare. Place detent ball on spring fig. Both coarse and fine pitch gears were used along with four different production ratios. All are helicoil cut except from the straight teeth reverse gear. This usually indicates that the gears used in the milled cases might be of a different steel alloy. The primary four-speed manual transmissions used by Chevrolet are the Saginaw, Muncie and Borg Warner models, with Saginaw and Muncie units being specifically made for Chevrolet.
The 3864848 case with the last 848 numbers milled off is in some full-size cars, such as the Impala. Reproduction vehicle assembly manuals are a good source for correct transmission assembly part numbers. The first letter in this number is going to tell you exactly which Saginaw transmission you have. Also, the reverse lever on the Muncie units is mounted in the extension housing, while the Saginaw reverse lever is mounted in the side cover Locate the serial number to differentiate 1969 and up Muncie transmissions. I created a Facebook page at www. Some have a boss for the switch that is cast but not machined on 1-2.
The easiest way to identify a Muncie transmission is by its side cover. External shift levers are secured with studs and nuts, others with bolts. The M-22 was generally installed behind severely powerful high torque big-block engines. Therefore, this is a LeMans case. It usually found its way into trucks and other heavy vehicles where weight was not at a premium. The basic Turbo-Hydramatic spawned two variants, the , and the. People often get confused about what a casting number is.
An extra heavy duty close-ratio version M-22 was also offered on many of the big-block high-performance models. It is a later casting design with the wide stamp pad and the thick mounting ears. Most of the books and articles I have seen, combined with some bits of Internet folklore, tend to have the same flaws because most information is copied and simply edited and resubmitted. Reliable sources to validate information regarding serial and casting numbers will get scarcer as time passes. The case has several unusual features.
Many rebuilders have bins full of tags. These cases were run in conjunction with the 3851325 case. This is a 4 speed, overdrive unit. I also had one of those 3-ring vega saginaw 4 speeds in a 50 chevy sedan delivery behind a healthy 406 small block and I was known to beat on it. A serial number is stamped into the case by hand, usually with numbered and lettered punches. In addition, due to engine and transmission swaps, and modifications that occur over the years many cars do not carry the original drivetrain that they were produced with.
The 6307N bearing has a 35-mm bore, an 80-mm outside diameter, and is 21 mm thick. We also recommend installation of all parts by trained professionals with the proper tools and equipment. There are also three drive pinion bearing retainer pilot sizes that serve as a basis for identifying transmissions. The Saginaw reverse shift lever is on the cover, and the cover has 7 bolts. I had about 10 of them, the most expensive was 80 bucks. If not, look up a small block 71 Nova to see if they list a kit for a Sag in that car. It is a date code for when the transmission was assembled based on the model year, not calendar year.
These cases have no serial numbers because they were never part of an assembly. Anyways, those old Hursts had a welded handle that you can't swap like a newer Hurst. Muncie identification Far and away the easiest way of telling them apart is what the transmission is made of. By late 1963 the rare 3839606 case started to show up in cars with a larger bearing bore. It is a later casting design with ers with bolt-on shifter shafts. The casting clock codes are at right above the fill plug. Remember, if the transmission is still in the car only the 1969 to 1974 cases had ratio identifiers in the serial number.
This could be an alloy improvement, a casting tool change, or some physical change. By 1963, wider gears improved the T10; this meant that the front bearing had to get narrow to compensate for the size difference of the front portion of the countergear. Others have a tag rivited to the case. The Turbo 375 was modified to accept the Turbo 350 driveshaft yoke. My 56 Sedan Delivery has a Muncie 4 speed; when the new engine goes in, a Borg Warner Super T-10 also goes in.
This was eliminated after 1963. This is a 1967 3885010 case dated June 2, 1967. These M22 units are highly sought-after for performance applications. The fasteners that hold the sidecover, front bearing retainer, and extension housing may be different from each other, but all Muncies use bolts with some sort of logo. I have a mount for a hurst shiter that mounts to the tail housing bolts and has a clamp that goes around the tail shaft by where the seal is. You would think that in nectors.
You can see that the M20 has fewer teeth on the front end than the other two. The number represents the month and the dots represent the week. The M-22 is distinguished from an M-21 by the angle of the gear teeth. Transmissions are marked and identified by: - Casting numbers on the case, extention housing and side cover on manual trans. It is unclear why there is the discrepancy. That would make me think that the original 4 speed in a factory built 71, must be a Saginaw, instead of the costlier Muncies. The Chrysler 4-speed was introduced during the fall of 1963 for the introduction of the 1964 models, and has since been produced in several different versions with various updates and modifications.