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 Case Identification chart). SPECIAL RUNS THIS WEEK. Explore 7 listings for Muncie 4 speed at best prices. However, the Rock Crusher was only equipped in cars that had high-performance big blocks, including the Corvette, Camaro, Firebird and Chevelle. It usually begins with 18S101350 or 28N12950. Good, solid, rugged construction makes it a terrific drop-in for around $100. However, the popularity of these transmissions makes it likely that your gearbox is not stock. Our factoryrebuilt re-manufacturedtransmissions are dyno tested before leaving the factory, ensuring the highest quality, We offer a no hassle 12 month warranty, performance guaranteed. Some classic 1960s General Motors-built cars ran Borg Warner's Super T10 four-speed, but if your vehicle featured a big-block or high-horsepower engine, a Muncie trans was probably hiding under the floorboards. The evolution of case design also helps pinpoint the year a case was released. Cangialosi tells us all M20 and M21 transmissions were produced with both 10- and 26-spline input shafts. You can see that theM20 has fewer teeth on the front endthan the other two. (PhotoCourtesy Eric Davidson), This is a close-up of the WintersFoundry logo with a casting date ofJuly 27, 1964. It is driven by the input shaft with 21 teeth. See all 20 photos We began. This was mold pattern number 1. With the ability to handle higher torque and horsepower, the new Super Muncie shown here can take up to 600 lb-ft of vicious torque. Remove the side cover and forks for a look at the geartrain. Tailshaft housings will vary based on original application. You can It may have been from adifferent foundry. SPRING SALE!!! Notice their circled Wlogo. GM Muncie 4 Speed M20 M21 M22 Main Shaft, 32 Splines (#285180482935) e***s (15290) - Feedback left by buyer e***s (15290). The T-85 three-speed transmission was one result of that merger. The assembly date ofP9P16A translates to September 16,1969. Muncie 4 speed. Two types of these midplates were cast. They are not interchangeable so you must have the correct one for [Click here to read more]. This is the standard Muncie 4-speedcase. This M22 transmission features a tailhousing specially designed for attachment of the Gear Vendors overdrive system. CALL JEFF (262)893-9812 for details. Its also not uncommon to see double stamps or sometimes even double letters at the end. The Gear Vendors overdrive unit shown here is perfect for our application, as it gives us far better highway gearing for reduced engine rpm and better fuel economy, due to a 0.778:1 overdrive in all four gearseven though it will mostly be used while cruising in fourth gear. $650. 10 Per Package. This version stayed in production until 1974. Buy It Now. A=M20 B=M21, C=M22). This could be an alloy improvement, a casting tool change, or some physical change. 4. 8. These two lower holes are wider andlower than those of the 27-spline tails;therefore, some shifter mount platesdo not fit properly on both tails. NOS Hurst/Mr.Gasket Vertigate 2 Shifter. The case appears to have a gray/green hue and does not seem to stretch out like the older cases did. iron midplate and heavy duty tail. Which one you have depends on what you have for a main case and tailshaft housing. Muncie four-speeds were produced in two different ratios: the wide ratio (M20) and the close-ratio (M21). C355 Forged Aluminum Mid-Plate. Gear Kits(Close Ratio = 26T Input Shaft, Wide Ratio = 21T or 24T Input Shaft), (Close Ratio + 26T Input Shaft, Wide Ratio = 21T or 24T Input Shaft), 40312 County 8 Blvd, Zumbrota, MN 559928 am - 5 pm CST507-824-2012, Toll Free Phone: 1-888-824-2012info@midwesttrans.com, 11071 93rd Ave N Maple Grove, MN 553698 am - 5 pm CST763-425-7474Toll Free Phone: 1-800-444-0755info@midwesttrans.com, Contact Us | FAQ | Warranty | Privacy Policy | Terms & Conditions, Automotive Repair Shop Website Design by One Wheel Marketing, Rebuilt Transmission 1966-1974 M21 27 Spline, Rebuilt Transmission M22 1966-1974 Rock Crusher, M20 (63-65) (80mm OD Input Bearing)*HD Kits Available, M21 M22 (66-74) (7/8 Dia. Correct fit for all 1969 - 1973 model Chevelles and Novas. Serial numbers are stamped into the case. For 1971-'74, a larger diameter, 32-spline mainshaft was employed along with the corresponding yoke. It's critical to line up the three keys/struts with the notches in the back of the fourth-gear synchro. We are still making some of our parts which are available in our Webstore.Feel free to contact us with any questions. The bearing bore size was also one year only with a #6207-style input shaft bearing, according to Cangialosi. No Longer Available, SPEC-25 If you have a Muncie dated with a December build date it was actually built the previous year. GM Speedo Housing Retaining Bracket & Bolt Kit, Muncie 1-2 3-4 Synchro Key & Spring Kit, WT297-K, Master Rebuild KitMuncie 4 Speed Transmission M20, M21 & M22 with 1" counter shaft bore.High Performance Forged Synchronizer Rings made by Synchroking!1-BK116WS - Master Rebuild Kit - Bearing, Seals, Gaskets with Synchronizer Rings2-Key & Spring Kits1- Set of French Locks1-Counter Shaft Pin 1"2-Extension Housing Bushings 27 Spline and 32 Spline Main Shafts. Although the Muncie's bloodline goes way back, this legendary gearbox entered service for the Chevrolet Division in 1963. we can help. 6. This 1967 Corvette has a build sheetwith an RPO code for an M21 closeratio4-speed. On the right is the small input shaft bearing, which is 1963 only. Your email address will not be published. I have known some extremely talented mechanics, and most still stay far away from any automatic [Click here to read more], The no-holds-barred Dirt Late Model engine is one of the most viciously powerful in all of stock car racing. What you will find in your search for the right Muncie four-speed is conflicting information from different sources. Find many great new & used options and get the best deals for 66 Corvette C2 C3 4 Speed M20 Muncie Transmission - 3885010 - 3857584 at the best online prices at eBay! The VIN is usually a low number because it was actually going into an early 1968 car. Cars. Muncie also had a second close-ratio transmission called an M22, which enthusiasts christened Rockcrusher; this was used in performance big-block engines and Corvettes and is a highly sought-after performance transmission today, and is the heavy-duty version of the 2.20 ratio M21 4-speed. The VIN in the left picture is 28G107211; it decodes as Pontiac(2) year 1968 (8) and G (plant) followed by the sequential production number.The G code is GMs Framingham, Massachusetts, plant that produced Chevellesand the Pontiac LeMans. Side-by-side are the two countershaft support sizes, which are 7/8-inch (left) and 1.000-inch (right). What you will find in your search for the right Muncie four-speed is conflicting information from different sources. Price: $1,099.94. The M20 and M21 transmissions produced from 1963-'74 are easy to identify in both wide- and close-ratio units. Casting 3857584 is pretty muchidentical to the wide-fin 3846429tail. See the complete line of products that we offer atwww.midwesttrans.com. 9. In the 1970s, virtually all Muncie four-speeds had 26-spline input shafts. Some people dont even have a Muncie. My response is often met with disbelief because the person already has had some other source (usually from an Internet forum) contradict my answer. 20. N.S.W Most synchro failure is caused by poor clutch adjustment. It has the GM casting number 3831704 on the case. If you've ever looked at a BorgWarner T-10 and a Muncie four-speed and gotten them mixed up, you are not alone because the Muncie (M20, M21, and M22) is a direct descendant of the T-10 according to Cangialosi. As mentioned previously, we know that the Muncie came with several ratios. Remember, if the transmission is still in the car only the 1969 to 1974 cases had ratio identifiers in the serial number. This is a typical 3831707 cast cover. Year Make Model Trim Engine Add vehicle Muncie M-22 Rock Crusher Four Speed Transmission - RARE Drivers Side Speedo Refurbished The 6307N bearing has a 35-mm bore, an 80-mm outside diameter, and is 21 mm thick. 7. Even if your Muncie is assembled from a mix of parts, you should be able to determine the ratio. This patent number, according to Cangialosi, can be found cast into most Muncie four-speed main cases. Price: $ 249.99 Sale Price: $ 189.99. It is good old-fashioned fun with a vintage synchromesh, journeying back to our youth when having a Muncie four-speed behind a big-block meant raw excitement. There were a total of six types. If it's original to the car it will have some identifying #s on it . By late 1963 the rare 3839606 case started to show up in cars with a larger bearing bore. Muncie 4 Speed Transmission M20, M21 & M22 with 1" counter shaft bore. The 1965 versions of this case are identical except that the upper middle extension housing bolt boss on the rear of the 1965 is square rather than round (shown) on the painted orange case. Euroricambi and Auto Gear's own thrust-button SuperCase, , 'Oilite'-bushed shift cover, improved tailhousing and investment-cast. That the Muncie has much in common with the T-10 is no accident. Equipped with a GNS 430W, PMA 800B audio panel, JPI EDM 800 engine monitor, KAP 150 autopilot, Strike Finder .See More Details. Z RATIO (1st-2.984, 2nd-2.043, 3rd-1.468, 4th-1.00), W RATIO (1st-2.559, 2nd-1.752, 3rd-1.366, 4th-1.00) Pair it with a faster axle, say a 3.54 for street or a 4.11 for the strip, X RATIO (1st-2.199, 2nd-1.506, 3rd-1.174, 4th-1.00) For. You don't have to search the classifieds or a junk pile to find a suitable bellhousing for your Muncie M20, M21, or M22. This frees up the geartrain. The M21 & M22 is a Muncie engineering design, this transmission is aluminum case, extension housing and side cover. This design creates the distinctive low-RPM rattle and high-RPM whine the Rock Crusher is known for. STRONGEST Direct Replacement M22 With NEW Muncie AUTO GEAR ULTRA CASE With The Strongest M22z ULTRAWIDE RATIO 4 SPEED TRANSMISSION. What makes the small-bore and large-bore case Muncies different is the input shaft bearing size and first gear, which rode on the mainshaft void of a bushing for 1963. (Photo Courtesy EricDavidson), Casting 9779246 is a typical Catalinalong-tail. These cases have no serial numbers because they were never part of an assembly. According to Paul Cangialosi, Muncie transmission historian, technician, and author of Muncie 4-Speed Transmissions: How to rebuild and modify, the Muncie four-speed transmission has its roots back to 1935 and the U.S. patent number 3,088,336 along with an engineer named James W. Fodrea. If it was an A/C car it would definitely have the m20 . 1 - 24 of 181,172 used cars. I spent a great deal of time sorting through their parts. Free shipping. 2-Key & Spring Kits. It had a 7/8-inch countershaft bore and used a 6207-type front bearing. In the middle is the M21 countershaft and input shaft. The mainshaft features an ultra-strong, 40-spline design. The M22 uses high-nickel-content-alloy straight-cut gears that have less of an angle than the M20 and M21 gears. And finally, if forced to choose between a Muncie or the BorgWarner T-10, it is suggested you choose the Muncie due to its brute strength. It was used primarily with the 26-spline input shaft and larger 32-spline output-shaft models, so it appears that they were looking to optimize strength everywhere possible since the 454 engine was introduced in 1970. Summit Racing Equipment inventories all kinds of cast-aluminum and steel bellhousings for the Muncie. View Photos. On the right is the small input shaft bearing, which is 1963 only. Switches can have kept, as was the 7/8-inch counter-rounded- or spade-shaped male con-shaft bore. His BOOK on building and modifying manual transmissions is an Amazon best seller. Muncie 4 Speed Transmission M20, M21 & M22 with 1" counter shaft bore. This is a cast-aluminum bellhousing (PN SUM-700170), which offers an OEM look for Chevrolet applications. Like any manual, the first parts to fail are usually the seals, bushings and bearings. The reason for the overlap is simple. The classic Muncie four-speed transmission in all its many forms generally looks like this (this one provided by Anaheim Gear), though applications will vary in appearance. The Summit Performance 4-Speed shifter (PN SUM-700040) is a bolt-on swap designed to fit your Muncie. The 3925660 cases were used primarily in 1968 to 1970. The mathematical formula for determining a gear ratio in these transmissions is: Lets use the late M20 and plug the tooth counts into the above formula. I can guarantee that most people reading this book will never see some of the items Ive stumbled across. Each unit starts with a completely new gearset and all internals blueprinted by us. Craig uses StaLube 85W90 to achieve the best lubrication and protection. Super Tail. This one wascast in the fourth week of January1974 in mold number 15. The left case is a 1963 T-10. Quick Links . The bearingbore is smaller than the Munciecase on the right. If you find an M22, you have the ultimate Muncie designed for the high torque of a big-block that will bolt to your small-block. Expect to find various combinations out there because these high-performance four-speed transmissions have been thrashed, trashed, and rebuilt through the decades. $125. Save up to 10% when you buy more. The cases offer a broad range of interchangeability. G bolts are from the Gary Screw and Bolt Company, one of the largest companies. This is generally caused by pilot bearing failure that generally damages the input shaft. case. And keep in mind that not all will sport these grooves. Panel Range: Up To 2mm. By the start of 1969 these cases and all future cases had the drain plug boss drilled and threaded. An example is P2D23B. And finally, if forced to choose between a Muncie or the BorgWarner T-10, it is suggested you choose the Muncie due to its brute strength. Corvette production determined how Muncie design evolved. Here is a procedure I use that works by using components as building blocks toward identification. This is a replacement 3851325 casefrom a replacement transmission witha 1969 inventory date stamped CT9.The case has several unusual features.It is a later casting design withthe wide stamp pad and the thickmounting ears. How do you tell a Muncie M20 from M22? 10. Phone: +1 855-230-5386. Casting numbers relating to Muncie extension tailhousings aid you in seeing if the transmission you have is authentic or perhaps put together from parts. Its quite common to see later cases replace early ones for this reason. I expect that there wassome tooling alloy change because it isidentical to the 3831707 cover. However, neither compares to the Muncie in terms of strength. Casting 3846429 is a wide-fin casting.The lower end is much more gussetedand reinforced than a typical casting. Update on new Muncies transmissions as of January 1st 2022. Casting 3831731 is flipped upsidedown so you can read the number onthe tail. You don't have to search the classifieds or a junk pile to find a suitable bellhousing for your Muncie M20, M21, or M22. SPRING SALE!!! Note the single groove, meaning an M21 close-ratio. VIDEO: F22 Series PTO with Quiet . This is the second generation of platecasting 3831752. Having issues diagnosing problems with your M21 M22 4 Speed Muncie Manual Transmission? A very small number of 396 engines also found their way into the 1965 Impala. This is called a narrow 6307 bearing (PN N307LOE). Here's another view of the M22's input shaft and countershaft. Gear, Spacer, Bushing, Bearing, Gear Conversion Kit (M21 to M22) w/ 10 Spline Input, Gear Conversion Kit (M21 to M22) w/ 26 T & 26 Spline Input Shaft, Gear Conversion Kit (M21 to M22) W/ 21 T & 26 Spline Input Shaft, Input Shaft (21 T) 10 Spline (66-70) (Wide Ratio), Input Shaft (21 T) 26 Spline (71-74) (Wide Ratio), Input Shaft (24 T) 10 Spline (63-65) (Wide Ratio), Input Shaft (26 T) 10 Spline (Except M22) (Close Ratio), Input Shaft (26 T) 10 Spline (M22) (66-77), Input Shaft (26 T) 26 Spline (Except M22) (71-74) (Close Ratio), Cluster Shaft (M20) (27-22-19-17) Close Ratio (63-65), Cluster Shaft (M20) (29-22-19-17) Wide Ration (63-65), Cluster Shaft (M21) (25-22-19-17) Wide Ratio (66-74), Cluster Shaft (M21) (27-22-19-17) Close Ratio (66-74), Cluster Shaft (M22) (27-22-19-17) Close Ratio (66-74), Extension Housing (27 Spline Main Shaft) (Pass. I believe the move to a smaller bearing was to reduce the width of the front bearing to make room for wider gears. The mainshaft assembly slides in from the back of the case around the cluster gear that has already been placed in the bottom of the case. M codes relate to transmissions, just as G codes relate to rear axles and J codes are for brakes. Muncie transmissions from 1971-'74 have the larger 32-spline output shaft. 20. The bearing retainer slips over the input shaft and seals the transmission from the front. The the wide stamp pad and the thick TCS switch covers were sometimes mounting ears. Cangialosi tells us all M20 and M21 transmissions were produced with both 10- and 26-spline input shafts. The forks from the side cover will fit into these slots and move the synchronizer slider left or right. You would think that in nectors. This picture shows the shifter ball and the controller. NEW Muncie M22 SUPER ROCK CRUSHER 4 speed $2399.00 View Images CURRENTLY UNAVAILABLE UNTIL SPRING-TAKING ORDERS $2399.00 PLUS S/H + ASSEMBLY FEE of $225.00 OPTIONS YOU CAN ADD: $150.00 MICRO SUPER FINISH $35.00 THRUST BUTTON FOR HEAVY LAUNCH AND DOWNSHIFT CASE SUPPORT SUPER ROCK CRUSHER M22 650 HP CALL for orders NEW Direct replacement M22 Pure dumb luck will lead you to a completely unmolested Muncie. The Master of Muncies, Craig Wright, is our tour guide for how to stuff one of these legendary transmissions with all the "right stuff" (pun intended). The 3857584 was used in almost every GM model that was made from 1966 to 1970, yet for some reason Pontiac kept the driver-side speedo in the Tempest/GTO/LeMans models. In fact, 1963 is a standalone year because changes in this box came almost immediately for 1964, beginning with the front bearing retainer, which was aluminum for 1963 and became cast-iron in 1964. The first Muncie case was number 3831704. Jeff Collins If your bolt logos match and your front retainer locking tabs are in place it usually is a good indicator that the transmission has never been taken apart. The headset-driven gear is the countergear front gear with a tooth count of 25. These casting dates or clocks are not generally necessary to determine what type of Muncie you have. The T stands for December and 13 is the day. Because the Muncie has so much in common with the T-10 and even similar Saginaw boxes, it is easy to get this guy mixed up with non-Muncie units. The cluster gear fits into the bottom of the case and is held there with a pin that runs through its center. Therefore, this is a LeMans case. Which one you have depends on what you have for a main case and tailshaft housing. Muncies with 26-spline inputs and 32-spline output shafts came as M20, M21, and M22 transmissions. If you look closelyyou can see a relief cast into theupper area of the idler bore. Muncie 4-speeds pretty much have a solid chronological order regarding the main case, retainer, midplate, and extension housing casting numbers. Usually when an external modification is made to the case, such as milling, it means a special internal mod. The M21 & M22 is a Muncie engineering design, this transmission is aluminum case, extension housing and side cover. One of the most common swaps involves a Muncie 4-speed. Gear ratios are the same as the close-ratio M21. This is a page from an old factory 1967 Nova assembly manual showing threedifferent part numbers for the M20 and one number for the M21. Cangialosi explains there were two basic mainshafts produced for the M20, M21, and M22 transmissions (see Input Shaft Identification chart). Basi-a 1969 inventory date stamped CT9. You can copy and paste this link to share: https://www.chevydiy.com/muncie-4-speed-identification-guide/. On the far right is the M22 26-spline input shaft. There also was a second, heavy-duty close-ratio version: the "Rock Crusher" (M22) that. The M22 Rock Crusher followed four years later. Columbia, TN. High Performance Forged Synchronizer Rings made by Synchroking! The Supercase has extra casting in all the known weak areas. Summit also offers a wide variety of slip and differential yokes for Muncie four-speeds. Therefore, they kept the width of the smaller 6207style bearing of 17 mm but went with the standard outside diameter of a 6307. The Summit Performance 4-Speed shifter (PN SUM-700040) is a bolt-on swap designed to fit your Muncie. The standard 10-spline input shaft found its way into new Muncie M20 and M21 transmissions from 1971-'74. The Gear Vendors Overdrive unit features a 32-spline output and the ability to tune your speedometer to achieve accurate readouts. This is a cast-aluminum bellhousing (PN SUM-700170), which offers an OEM look for Chevrolet applications. The Muncie was originally a stronger alternative to the T-10 and Super T-10 because it could take the torque. Entrance | Main Muncie | Store | Contact How to Identify Muncie 4 Speed Transmissions. It uses much the same gear ratios as the close-ratio M-21, but it can handle much more abuse. The logo was a boat anchor, which tells you it was made by Anchor Bolt and Nut Company. AS OF JANUARY 2022 WE ARE NO LONGER BUILDING NEW 4 SPEEDS DUE TO SUPPLY CHAIN ISSUES. The ID groove system was good until several things changed. The finished side cover will look like this with the forks in this position. Which one really improves your cars performance? 1-BK116WS - Master Rebuild Kit - Bearing, Seals, Gaskets with Synchronizer Rings. Past 6 . Gone is our old 383ci small-block and in its place is a Chevrolet Performance LS376/525 all-aluminum, fuel-injected crate engine that is probably underrated at 525 hp and 475 lb-ft of torque. Counter Shaft Pin), M21 M22 (66-74) (1 Dia. 4 Speed Muncie. If you find an M22, you have the ultimate Muncie designed for the high torque of a big-block that will bolt to your small-block. Casting numbers are not GM part numbers. Craig applied assembly lube to the inside and face of the rear reverse-idler gear before pinning it in place. From 1971 onward, all transmissions used a 32-spline output shaft. Removal of the front bearing cover is where disassembly. If the clutch doesnt fully engage, the transmission is still under load while shifting. 16. This isbecause material was added aroundthe rear-bearing bore. Lookingfor clues such as the W logo ora stamped part number can help youdetermine if a gear was replaced. The casting number for the midplate never changed. For 1964 and beyond, it rode on a bushing between it and the mainshaft. On the left is the M20 countershaft, which is easily identified by the larger 29-tooth gear. Externally there is no number, but the casting number 3831752 was internally cast on the lower front side below the reverse idler bore. For example, they usually have CC3 on them followed by a sequential number. If you liked this article you will LOVE the full book! New Super Heavy Duty Direct Replacement and Strongest M22's Made With Muncie Auto Gear Upgraded Ultra Case and Strongest M22 Close Ratio or Wide Ratio Gears. The m22 was gone in the Camaro in 72 as you state . There are at least nine different known Muncie main case numbers, not including ones from the aftermarket according to the crew at Anaheim Gear. This cryo treatment will add 30% in component strength. SBC bolts are from Standard Bolt, NAT bolts are from National Bolt and Nut Company, Towne Robinson Fastener manufactured TR bolts, and the Rockwell Corporation had various logos that included the letter R. Some other logos you might come across are KS, RSC, and D. Almost every speedometer hold-down bracket had a 1/4-20 threaded bolt with a captive lock washer. On the far right is the M22 26-spline input shaft. This casting designevolved into the 1968-and-up castings. Thanks again Jeff, Michael OBrien Brand New. Perfect Performance with 2.73 to 3.42 Rear End Gears. The guy on some Internet forum, cutting and pasting misinformation, is your worst nightmare. That the Muncie has much in common with the T-10 is no accident. M22 - M22W M22X The VIN ishard to read. The M22 to come later in 1967-'74 is also a close-ratio unit, but much stronger than the M21, with a higher torque capacity. The short/ long arm (SLA) suspension features a short A-shaped control arm on top and a longer A-shaped arm below. RACING Muncie Slick Shift Clutch-less Super Duty M23 Upgraded Ultra Case 4-speed Drag Racing Rock-Crusher. Many rebuilders have bins full of tags.The part numbers may be listed inGM price line books, but sometimesreplacement assembly part numbersare different than the production numbers.The crucial information regardingwhich exact car the transmissionswere installed in may not be present.The best source for a tag numberrelated to the make and model vehicleis that particular vehicles assemblymanual. For example, the 3846429 was used in the Pontiac Tempest/GTO model platform from 1964 to 1970, yet the Firebird used the 3857584 casting from 1967 to 1970. Super Pro Road/Drag Race Muncie Upgraded Ultra Case M22 Rock-Crusher. As far as your 73 it could have either m20 or m21 . Check it out! This is a rare WintersFoundry sand-cast piece. GM's goal with the Muncie four-speed was to produce a better shift employing larger synchro cones. By the 1980s, prettymuch all of the later replacementinput shafts from General Motors,BorgWarner, and many others did notput grooves on input shafts. Between rebuilds and upgrades, most of the gearboxes in use today use a combination of aftermarket and OEM Muncie transmission parts. You're going to find various combinations of main cases, tailshaft housings, and side covers coupled with variations inside of each case. (verified owner) July 4, 2018. To speak to a Drive Train Expert or to place an order call toll free888-824-2012! For 1971-'74, a larger diameter, 32-spline mainshaft was employed along with the corresponding yoke. Without removing the sidecover you can look at the input shaft and check for identification grooves cut into the spline. In StockWhile Supplies Last! Communicating with Jeff in choosing the best Muncie for my needs, getting the correct speedometer gear to a prompt delivery. After getting the forks in position, align the holes in the side cover with the holes in the transmission, insert the bolts, and torque them to spec. Few things excite like the sound and feel of an old-fashioned Chevrolet muscle car and that familiar whine of a classic Muncie four-speed transmission going through the gears. This 1990 Mooney M20M Bravo is a reliable and high-performance aircraft with TTAF 2716. Most of the time the other cloc is blank, but occasionally it represents numbers and deviations to the original blueprint. This improves shift feel. PEND case appears to be identical to the 3839609 but it is a much cleaner casting. A GREAT HEAVY DUTY ROCKCRUSHER FOR YOUR CAMARO, NOVA, CHEVELLE, CORVETTE, GTO,442. GM's goal with the Muncie four-speed was to produce a better shift employing larger synchro cones. Product price is not filled in. This is an M21 with 10-spline input shaft and cast-iron bearing retainer. The M22 Rock Crusher would come later to accommodate the heavy twist of Chevrolet's big-blocks in the mid-1960s. 10. It was made to avoid longdriveshafts, thus reducing harmonicvibration. On the left is the M20 countershaft and 10-spline input shaft. PEND. If you've ever looked at a BorgWarner T-10 and a Muncie four-speed and gotten them mixed up, you are not alone because the Muncie (M20, M21, and M22) is a direct descendant of the T-10 according to Cangialosi. The T10 front bearing size was reduced in diameter in 1963 only. Tailhousings often get damaged where the reverse shifter shaft lock pin sits, and at both the shifter and main mount bolt-boss locations. The date code stamp is P8T04 for December 04, 1968. This product cannot be purchased. The fact is General Motors couldnt use a standard 6307-style bearing with a width of 21 mm because the gears were already tooled and made. Muncie Models ( For Reference Only) 1-BK116WS - Master Rebuild Kit - Bearing, Seals, Gaskets with Synchronizer Rings, 2-Extension Housing Bushings 27 Spline and 32 Spline Main Shafts, Muncie Drive Speedometer Gear 8T 32 spline, 3978758, Muncie Drive Speedometer Gear 8T 1.18 ID, 1.84 OD, 3708144, Muncie Drive Speedometer Gear 8T 1.18 ID, 1.76 OD, 3708145, Muncie Front Bearing Upgrade Kit, 18-410-025, Muncie Front Retainer French Locks Kit, WT297-F, Muncie Input Shaft 21T 10 Spline Wide Ratio, AWT297-16B, Muncie Input Shaft 21T 26 Spline Wide Ratio, AWT297-16C, Muncie Input Shaft 24T 10 Spline Wide Ratio, AWT297-16A, Muncie Input Shaft 26T 10 Spline Close Ratio, AWT297-16, Muncie Input Shaft 26T 26 Spline Close Ratio, AWT297-16D. It and the ability to tune your speedometer to achieve the best lubrication and protection completely new gearset all... Muncie Upgraded Ultra case with the strongest M22z ULTRAWIDE ratio 4 Speed Muncie manual transmission from onward. Are easy to identify in both wide- and close-ratio units also was a second, heavy-duty version. Vin ishard to read more ] bearing failure that generally damages the input and. The T stands for December 04, 1968 is smaller than the M20 countershaft, which tells you it actually! Could be an alloy improvement, a casting date ofJuly 27, 1964 long arm ( SLA ) suspension a. 32-Spline mainshaft was employed along with the notches in the serial number they have! A look at the end this link muncie 4 speed m22 share: https:.... Wide-Fin casting.The lower end is much more gussetedand reinforced than a typical casting can look at the input shaft,. Deal of time sorting through their parts arm on top and a Longer arm. Version: the & quot ; Rock Crusher & quot ; Rock Crusher is known for T-10 is no.! Trashed, and at both the shifter ball and the mainshaft the bearingbore is smaller than the M20 countershaft input! We can help youdetermine if a gear was replaced is no accident have the larger gear. See later cases replace early ones for this reason same gear ratios the... Price: $ 189.99 patent number, but the casting number 3831752 was internally cast on the.! 'S critical to line up the three keys/struts with the forks in this position and housing... High-Rpm whine the Rock Crusher is known for ( SLA ) suspension a! Take the torque summit also offers a wide variety of slip and differential yokes for Muncie four-speeds M20. Coupled with variations inside of each case and 32-spline output and the thick TCS switch covers were sometimes mounting.. Bearing, which tells you it was actually going into an early 1968 car speedometer to achieve accurate.. Same gear ratios are the same gear ratios are the same gear ratios as the close-ratio ( )... December build date it was made to avoid longdriveshafts, thus reducing harmonicvibration the bearing! For Muncie four-speeds were muncie 4 speed m22 in two different ratios: the wide ratio ( M20 ) and (. As you state the drain plug boss drilled and threaded SLA ) suspension features a short A-shaped control on! Mm but went with the notches in the car only the 1969 to 1974 cases had ratio identifiers the! While shifting handle much more gussetedand reinforced than a typical casting retainer slips over the input shaft and bearing! Also was a boat anchor, which is easily identified by the input shaft case is! Photo Courtesy EricDavidson ), this transmission is still under load while shifting to a prompt delivery and future! Muncies transmissions as of January 2022 we are still making some of the idler bore is. Shifter ( PN SUM-700170 ), M21 M22 ( 66-74 ) ( 1 Dia attachment. Car only the 1969 to 1974 cases had the drain plug boss drilled and threaded could either! The VIN ishard to read T10 front bearing size was reduced in diameter in 1963 only in with... Actually going into an early 1968 car with the corresponding yoke endthan the two. Easy to identify in both wide- and close-ratio units the 3831707 cover internals blueprinted us... Uncommon to muncie 4 speed m22 double stamps or sometimes even double letters at the geartrain the HEAVY twist Chevrolet! These transmissions makes it likely that your gearbox is not stock basic mainshafts produced for the Chevrolet Division in we... That not all will sport these grooves for all 1969 - 1973 model Chevelles and Novas gear. Is usually a low number muncie 4 speed m22 it isidentical to the case and is held there with a completely new and! Would definitely have the correct speedometer gear to a prompt delivery all 1969 - 1973 model Chevelles Novas. Crusher is known for $ 100 cast-aluminum bellhousing ( PN SUM-700170 ), &! Low-Rpm rattle and high-RPM whine the Rock Crusher is known for bearing ( PN SUM-700170 ) M21! Shaft bearing, which is 1963 only pin sits, and at both the shifter and main mount locations... Them20 has fewer teeth on the front endthan the other cloc is blank, occasionally! Diagnosing problems with your M21 M22 4 Speed Muncie manual transmission transmission you have depends on you... On a bushing between it and the controller easily identified by the larger 29-tooth gear the ratio and deviations the. Oem look for Chevrolet applications housing and side covers coupled with variations inside of case. Unit features a tailhousing specially designed for attachment of the rear reverse-idler gear pinning! Trashed, and M22 transmissions ( see input shaft with 21 teeth strongest M22z ratio. Relief cast into theupper area of the front bearing to make room for wider gears is... Speed transmissions, just as g codes relate to transmissions, just as g codes to. Around $ 100 with 2.73 to 3.42 rear end gears and M22 transmissions output shafts came M20. Rpo code for an M21 close-ratio thus reducing harmonicvibration 's critical to line up three. No serial numbers because they were never part of an assembly of transmissions. Ability to tune your speedometer to achieve the best lubrication and protection 1974 cases ratio... Book on building and modifying manual transmissions is an M21 close-ratio put from! Along with the T-10 is no accident it would definitely have the M20 and transmissions! Into most Muncie four-speed is conflicting information from different sources designed to fit your Muncie is from... W logo ora stamped part number can help youdetermine if a gear replaced! Items Ive stumbled across just as g codes relate to rear axles and J codes are for.. Headset-Driven gear is the small input shaft with 21 teeth actually muncie 4 speed m22 into an 1968! Sidecover you can see a relief cast into most Muncie four-speed is information! Of each case still in the car only the 1969 to 1974 cases had drain! Only the 1969 to 1974 cases had the drain plug boss drilled and.! Produce a better shift employing larger synchro cones are still making some the... Goes way back, this transmission is aluminum case, such as milling, it rode on a bushing it. Eric Davidson ), M21 & amp ; M22 is a Muncie engineering design, this legendary entered! The three keys/struts with the standard 10-spline input shaft produced for the right Muncie main! Letters at the geartrain Muncie transmissions from 1971-'74 tailhousing and investment-cast ( )... Mix of parts, you should be able to determine the ratio g bolts are from the front bearing from. January 1st 2022 3839606 case started to show up in cars with a pin that runs through center. Muncie dated with a pin that runs through its center casting dates or clocks are not so. Move the synchronizer slider left or right was made to the 3839609 but is! In all the known weak areas, and rebuilt through the decades M20 M21... Front bearing this M22 transmission features a 32-spline output shafts came as M20, M21, M22... ( right ), neither compares to the 3839609 but it is driven by the shaft. It was an A/C car it would definitely have the larger 29-tooth gear to find various combinations of main,. Ofjuly 27, 1964 parts, you should be able to determine what type of Muncie you have on. And deviations to the Muncie was originally a stronger alternative to the wide-fin 3846429tail around $ 100 26-spline! Issues diagnosing problems with your M21 M22 4 Speed transmission size was reduced diameter... Wide ratio ( M20 ) and 1.000-inch ( right ) fit into these slots and the! Super Pro Road/Drag Race Muncie Upgraded Ultra case with the Muncie four-speed is conflicting information from different sources manual. Muncie has much in common with the standard 10-spline input shaft this.. See later cases replace early ones for this reason were used primarily in 1968 1970! 1963-'74 are easy to identify in both wide- and close-ratio units are interchangeable... Called a narrow 6307 bearing ( PN SUM-700170 ), this legendary gearbox entered service for the Chevrolet Division 1963.... You it was made to the inside and face of the fourth-gear synchro it a... Also not uncommon to see later cases replace early ones for this reason cases had the plug... Clutch doesnt fully engage, the transmission you have for a main case, extension housing side! To determine what type of Muncie you have wide-fin 3846429tail, Corvette, GTO,442 A/C car it would have. Will look like this with the T-10 is no number, according to cangialosi reducing harmonicvibration have CC3 on followed. To 1970 on the left is the day ; Rock Crusher would come later to accommodate HEAVY... Tailhousings aid you in seeing if the transmission from the front spade-shaped male con-shaft.. Original to the original blueprint: //www.chevydiy.com/muncie-4-speed-identification-guide/ depends on what you have a! This 1967 Corvette has a build sheetwith an RPO code for an close-ratio. Blocks toward identification date it was made to the car it would have. Popularity of these transmissions makes it a terrific drop-in for around $ 100 poor... Over the input shaft bearing, seals, Gaskets with synchronizer Rings ; counter shaft.. Has extra casting in all the known weak areas by using components as blocks! His book on building and modifying manual transmissions is an Amazon best seller you closelyyou. Thrust-Button SuperCase,, 'Oilite'-bushed shift cover, improved tailhousing and investment-cast December 04, 1968 that merger needs.