Counter Shaft Pin), M21 M22 (66-74) (1 Dia. According to Cangialosi, two companies, Borg and Beck and Warner Gear, merged in 1928 to form BorgWarner. This casting designevolved into the 1968-and-up castings. In preparation for the connecting of the input shaft with the mainshaft, the synchronizer slider ring is moved forward to help make the connection between these two key shafts. The T10 front bearing size was reduced in diameter in 1963 only. All ball bearings have standardized numbers used by the bearing industry. 1- Set of French Locks. We have the best prices on Muncie 4 speed parts, including Chevy Muncie 4 speed transmission parts, and we can guarantee you a great selection of items extending from the Casting 384362 is the long-tail versionwith a driver-side speedo. Later cases seem to only have one clock. Muncie 4 speed. Ready to be filled, install and it's available at a great price. allclassifieds.ca. By late 1963 the rare 3839606 case started to show up in cars with a larger bearing bore. Includes all the goodies: SuperCase, gear ratio choice, heavy-duty set with a oilite bushed side cover. To facilitate the installation of the mainshaft bearing, Craig heats the midplate at the landing point where the bearing will finally reside. Muncie four-speeds were produced in two different ratios: the wide ratio (M20) and the close-ratio (M21). The mountingears also have thicker gussetsthan earlier cases. The T-85 three-speed transmission was one result of that merger. Thanks to the similarities between the M20, M21 and M22 transmissions, you can use a combination of Muncie 4-speed transmission parts to build the transmission you want for your project car. The mid plate is aircraft grade aluminum. These are usually the firstnumbers used to start the identificationprocess. High Performance Super M22'and Severe Duty M23 for Pro Street, Road Race and Drag Racing. And keep in mind that not all will sport these grooves. 15. Screw Size: M4.8 (#10) Center Of Hole To Edge: 10mm. One of the most common swaps involves a Muncie 4-speed. Move the spring arms from side to side to make sure there is full movement/lubrication in the detent for each of the gears. If it's original to the car it will have some identifying #s on it . Lead time 4-6 weeks. This cryo treatment will add 30% in component strength. 2-Key & Spring Kits. Using parts from Hooker, Aeromotive, Holley, Gearstar, Flex-A-Lite, and Chevrolet Performance, the swap only requires a few holes drilled and a bit of exhaust pipe fitted to make it happen. This is April 23, 1972, M21 ratio. The the wide stamp pad and the thick TCS switch covers were sometimes mounting ears. When you have the two side-by-side it becomes obvious which is which. 9. 13. Muncie transmissions also tend to get performance improvements such as a gear ratio change and stronger internal parts. 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. 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. There are three basic types of Muncies: M20, M21 and M22. By late 1964 the 3851325 case was cast with GM Patent Number 3088336. M20 transmissions have two grooves on the input shaft, M21 transmissions have one groove, and M22 transmissions have no grooves. On the left is the M20 countershaft and 10-spline input shaft. It duplicatesthe short extension mounting andshifter locations. According to Cangialosi, GM took the basic T-10 design and beefed it up to conceive the Muncie M20 and M21 four-speed transmissions, which arrived in 1963. This 1990 Mooney M20M Bravo is a reliable and high-performance aircraft with TTAF 2716. Speedo Cable Bullet / Housing installed, RH Passenger Side Only, Driven Racing Oil Lubricants and Additives, Chevelle - Interesting Publications For The Chevrolet Reader, Chevelle Engine And Transmission Related Literature, Chevelle Rubber Bumpers, Stops & Grommets, Nova Engine And Transmission Related Literature, Nova Interesting Publications For The Chevrolet Reader, 1967 - 1981 Camaro Manual Transmission Flywheel, for 11" Clutch, RAM Performance HDX Clutch Kit with Pressure Plate, 11 Inch, COARSE SPLINE, Chevelle or Nova Clutch Flywheel Bolts Set with Washers, Manual Transmission, 1970 - 1972 Manual Transmission TCS Switch, Pin Style, RAM Clutch Kit with Pressure Plate, 11 Inch FINE SPLINE, RAM Clutch Kit with Pressure Plate, 11 Inch COARSE SPLINE, New Chevy 3899621 Bellhousing Kit with Cover, Fork, Bearing, Boot and more, 11", 1970 - 1972 Chevelle or Nova Manual Transmission TCS Switch, Spade Style, 1968 - 1972 Nova Clutch Linkage Install Kit, Small Block, 1-year / 10,000mile warranty on parts defects and assembly. 1-BK116WS - Master Rebuild Kit - Bearing, Seals, Gaskets with Synchronizer Rings 2-Key & Spring Kits 1- Set of French Locks 1-Counter Shaft Pin 1" 2-Extension Housing Bushings 27 Spline and 32 Spline Main Shafts I spent a great deal of time sorting through their parts. Glean the basics and use them in your research. 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. A gear ratio is a combination of two ratios multiplied together. And keep in mind that not all will sport these grooves. The Muncie four-speed, like the T-10, is a side-loading transmission. It is a date code for when the transmission was assembled based on the model year, not calendar year. The Saginaw four-speed box is quite similar to both the T-10 and Muncie four-speed transmissions. 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. Perhaps an alloy change as well as a tooling change warranted a new number. Again, Thank You for the great customer service. 1-BK116WS - Master Rebuild Kit - Bearing, Seals, Gaskets with Synchronizer Rings. From left to right are the three basic Muncie input shaft/countershaft combinations. This picture shows the shifter ball and the controller. Usually a casting number is changed because of a design change. From 1969 to 1974 all-ratio Muncies came with drain plugs. The first Muncie copied the smaller bearing and retainer combination of the T10. With the introduction of the 3885010 case, the countershaft bore was increased to 1 inch. All M22s use a 26-spline shaft made from a stronger alloy than the other 4-speeds. From 1967 to 1968, the serial number used year, month, and day designators; the month designator is now a letter. 6. The 19691974 Muncies received a ratio designator at the end of the serial number: A for M20, B for M21, C for M22. M22 Complete Geartrain Muncie 4 Speed. 8. There were a total of six types. The countergear has 17 teeth on its first-gear section driving the actual first-speed gear with 36 teeth. It has a seven-digit serial numbercast into the case on the passengersside. When you have the two side-by-side it becomes obvious which is which. M22 - M22W M22X 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. Counter Shaft Pin) *HD Kits Available, M21 M22 (66-74) (1 Dia. In the 1970s, virtually all Muncie four-speeds had 26-spline input shafts. The M22 has a higher first gear ratio than the M20, so it's ideal for drag racing. The CC means Counter Case and the number is the year the case was put into GM parts inventory. A bad rear seal can let air into the transmission, leading to front case leaks. Free shipping for many products! 20. The Muncie was originally a stronger alternative to the T-10 and Super T-10 because it could take the torque. Gear ratios are the same as the close-ratio M21. What you can see is that before March 1965 these cases were not milled. The cheapest offer starts at $ 3,500. Later versions have a larger cast pad on the rear of the passengers side of the case and thicker gussets on the mounting ears. Simply put, it is the number that is actually cast into the case when the molten aluminum is poured into the case mold. The casting number for the midplate never changed. However, the 19641965 3851325 casting number waskept, as was the 7/8-inch countershaftbore. This product cannot be purchased. The reason for the overlap is simple. 4. A 4 next to the casting is the mold pattern number. AUSTRALIA, Your email address will not be published. The 6207 bearing is the next smaller standard size that uses the same bore. N.S.W Notice the other lettersand the type of options they represent.Because M21 is just a code, laterCorvettes or other 4-speed cars didnthave Muncies; those equipped with aSuper T10 4-speed could have an M21or an M20 code. Two types of these midplates were cast. Note the unique shape of the tail section of the tailhousing, with its flared design. 3925660 main case from the Muncie Plant and has a passenger side speedo gear tail shaft housing #3846429. 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. I can guarantee that most people reading this book will never see some of the items Ive stumbled across. Some cases may look identical and have a different casting number but have the same GM part number. to get correct speedo gears installed in your new transmission. 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. Tailshaft housings will vary based on original application. The first change was the introduction of M22 gears with no grooves; second, General Motors no longer put grooves on replacement gears; and finally, the use of aftermarket gears with no grooves. Expect to find various combinations out there because these high-performance four-speed transmissions have been thrashed, trashed, and rebuilt through the decades. The large-bore Muncie came into production in 1964-'65 and became the standard from then on through the end of production in 1974. have the same ratios in the 26 spline input and 32 spline output SPRING SALE!!! The 6307N bearing has a 35-mm bore, an 80-mm outside diameter, and is 21 mm thick. Opens in a new window or tab. Good, solid, rugged construction makes it a terrific drop-in for around $100. This was eliminated after 1963. 4. A GREAT HEAVY DUTY ROCKCRUSHER FOR YOUR CAMARO, NOVA, CHEVELLE, CORVETTE, GTO,442. CALL JEFF (262)893-9812 for details. This is a 1970 M20 case. 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. Remove the side cover and forks for a look at the geartrain. The replacement case (GM PN 3925659) was used for all 1966 1974 Muncies as listed in the GM AC DELCO 1978 service parts manual. The first Muncie case was number 3831704. Muncie transmissions from 1971-'74 have the larger 32-spline output shaft. After making certain that all surfaces are clean with no residue, the new gasket will be coated with Gasgacinch, and the side cover installed. It was much easier to stockpile Muncie spare parts and cores in the 1970s than it is today. 12. 5. 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. It uses much the same gear ratios as the close-ratio M-21, but it can handle much more abuse. 5speedscom (7,130) 100%. In contrast, close-ratio transmissions (which use a 2.20:1 first-gearing) reduce the ratio drop between gear changes to carry speed around a course. According to Cangialosi, the date was based on model year, not necessarily the calendar year. Because this mainshaft is larger, you're also going to need larger bushings and seals. Its also not uncommon to see double stamps or sometimes even double letters at the end. Tailhousings often get damaged where the reverse shifter shaft lock pin sits, and at both the shifter and main mount bolt-boss locations. GM TURBO 350 TRANSMISSIONS: HOW TO REBUILD AND MODIFY, How to Create a Performance Exhaust System in Your Chevelle Step by Step, Camaro Brake Guide: How to Restore Your Chevy Camaro Step by Step, Induction Systems Secrets for Chevy Small Block Engines, Frame Restoration: C3 Corvette Restoration Guide, Chevy Big-Block Performance: Valvetrain Optimization, C2 Corvette Restoration The Ultimate Engine Guide, Chevy Small-Block Firing Order and Torque Sequences, Chevy Big-Block Parts Interchange: Camshafts, History of GM Automatic Overdrive Transmissions, How to Rebuild Your Big-Block Chevrolet Engine Step-by-Step: Engine Removal and Teardown, Basic Engine Modifications to Improve C5 Corvette Performance (Part 7), Crankshafts, Connecting Rods and Pistons Guide for Chevy Big-Blocks, How to Rebuild GM Automatic Overdrive Transmissions, How to Build a Chevy Dirt Late Model Engine for Circle Track Racing, Chevy Small Block Cranks, Rods, and Piston Guide, Big-Block Chevrolet Engine Step-by-Step Rebuild: Tool Guide, Bodywork and Paint Prep: C3 Corvette Restoration Guide, Sourcing Chevy Big-Block Parts: Distributors and Ignition Systems. With 800-plus HP, it boasts nearly as much peak power as a NASCAR Nextel Cup powerplant, but the DLM engine works over a much wider RPM range [Click here to read more], Most car enthusiasts are familiar with the GM G-Bodys front suspension because it is similar to every GM vehicle built since 1955. On the right is the M22 countershaft with 27-teeth. This usually indicates that the gears used in the milled cases might be of a different steel alloy. The early M20 with the 24-tooth input only came in 10-spline. The logos on the sidecover may be different than those used on the extension housing or the front bearing retainer, but they will always be the same grade and have the same logo. You can copy and paste this link to share: https://www.chevydiy.com/muncie-4-speed-identification-guide/. C355 Forged Aluminum Mid-Plate. 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. This version stayed in production until 1974. A great Super Heavy Duty Rock Crusher M22 for your Camaro, Nova, Chevelle, Corvette or other GM car. Limited Quantity!! Typically, when you ordered a GM car you had standard options and accessories installed. SPRING SALE! For 1971-'74, a larger diameter, 32-spline mainshaft was employed along with the corresponding yoke. . Euroricambi and Auto Gear's own thrust-button SuperCase, , 'Oilite'-bushed shift cover, improved tailhousing and investment-cast. The main case will sport a seven-digit casting number (found above the US Patent No), which is not a GM part number. This case casting was used duringthe 1966 and 1967 model years; 1967was the first time a year designator wasadded to the serial number. For 1964 and beyond, it rode on a bushing between it and the mainshaft. This is the M22 17 degree gear set of the famed "Rock crusher" in original "close" ratio, which are as follows, 1st gear 2.20 to 1, 2nd gear 1.64 to 1, 3rd gear 1.28 to 1 and 4th 1 to 1. 21. 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. Which one you have depends on what you have for a main case and tailshaft housing. You must look at the gear ratios to tell a Muncie M20 from an M22. 10 OR 26 spline input and large 27 OR 32 spline output shaft. Here is a rare 3925661 casting froma 1969 Camaro. Summit Racing Equipment inventories all kinds of cast-aluminum and steel bellhousings for the Muncie. Use Lubriplate 105 on the synchronizer slots. Casting number revisions are always chronological, which means that a higher number corresponds to a later part. PEND. cast above General Motors Corp. Notice that the drain plug boss was not drilled out. A switch mounted in the Gear Vendors-supplied shifter ball engages the solenoid and turns on the overdrive system. Main This isbecause material was added aroundthe rear-bearing bore. Before you here are the basics of Muncie M20, M21, and M22 four-speed transmissions. Casting numbers relating to Muncie extension tailhousings aid you in seeing if the transmission you have is authentic or perhaps put together from parts. The M22 uses high-nickel-content-alloy straight-cut gears that have less of an angle than the M20 and M21 gears. Tailshaft housings will vary based on original application. He tells us both the M20 wide-ratio and M21 close-ratio transmissions were first offered in 1963. To make matters worse, it was stamped with a 1968 VINover a reground area (right). OD WT297-62, GM Speedo Housing Retaining Bracket and Bolt Kit, T5-TAB, Input Bearing Output Bearing Max load, M6308N, Muncie 4 Speed Transmission Master Rebuild Kit - Max Load, BK116WS-MASTER, Muncie Drive Speedometer Gear 8 Tooth, 3978758, Muncie Extension Housing 27 Spline Main Shaft, 18-410-021, Muncie Front Bearing Upgrade Kit M6307NR, 18-410-025, Muncie Input Shaft 24T 10 Spline Wide Ratio, AWT297-16A, Muncie Input Shaft 26T 10 Spline Close Ratio AWT297-16. Ive met many of these rebuilders and have had the pleasure to create great friendships with them. The bearing retainer slips over the input shaft and seals the transmission from the front. In Stock. It may have been from adifferent foundry. 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. I created a Facebook page at www.MuncieBook.com. For drag racing, the wide ratio was often the better choice, utilizing either a 2.56 or 2.52 first-gear ratio. They all seem to come from big-block cars. . 20. There is no point restampinga case unless you can do it right. Retaining the 4-speed with your LS swap is a perfect blend of old and new. Without removing the sidecover you can look at the input shaft and check for identification grooves cut into the spline. This is when you have to remove the side cover to see what's inside. Note that all of the bolts will have to be removed to attach the tailhousing. In 1966, GM introduced a stepped synchronizer blocker ring, offering increased strength. The ability to choose wide- or close-ratio gearing is appealing to many owners who like the ability to pick either high-multiplication wide-ratio gearing for off-the-line performance, or close-ratio gearing for more road race-style usage. The early 3851325 PAT. 10 Per Package. Serial numbers for Muncie 4-speeds always begin with the letter P, which stands for Muncie Plant (not passenger car.) M and N were used to identify 3-speed Muncies; O identifies the Saginaw 3-speed with overdrive. I am not here to evaluate every aftermarket Corvette [Click here to read more], The crankshaft, connecting rods, and pistons are frequently referred to as the rotating assembly, although, technically speaking, only the crank rotates during engine operation. Every first gear has 36 teeth, second gear has 30 teeth, and third gear has 27 teeth. 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. Us | Rebuild Kits | Muncie Anything after that time period will say US Patent No 3088336. A very small number of 396 engines also found their way into the 1965 Impala. You really cannot get the early M20 and M22 mixed up because the early M20 came with a 7/8-inch countershaft, while the M22 did not. So how did the ratios change? Corvette production determined how Muncie design evolved. 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. Anything after that time period will say US Patent No 3088336. The side cover has seven bolts and two shift cams. or a mix of spline combinations at no additional cost. Wide Ratio = 2.56-1st, 1.75-2nd, 1.36-3rd, 4th direct Built for big HP. 5. Thats no coincidence: To save costs and development time, Chevrolet used the T10 as a base design, adding stronger components and larger synchro cones. Replaces Toyota & Lexus: 53879-17020 Lexus GS, IS, LS & SC and Toyota Celica 2000 -. 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. If you examine the 1966-'70 wide-ratio M20 input shaft, there are two grooves cut amid the 10 splines. Tooling up for a die casting isvery expensive. This cover has the better hat-stylepivot pin. It usually begins with 18S101350 or 28N12950. This was mold pattern number 1. Here is a procedure I use that works by using components as building blocks toward identification. For 1971-'74, a larger diameter, 32-spline mainshaft was employed along with the corresponding yoke. Before you here are the basics of Muncie M20, M21, and M22 four-speed transmissions. Save up to 10% when you buy more. One more way to identify the Muncie is via stamped codes in the case, which indicate when the transmission was built at Muncie (see How To Read Muncie Build Date Codes chart). Resources: Products. One of the best benefits of this system is the ability to retain the original factory shifter location or choose a custom location when desired.. The basic design and operation theory of the gearbox changed little during that time, though several design upgrades and modifications were made during the total production run. Muncie 4 speed 3831752 M20 M21 M22 Midplate Intermediate Bearing Retainer NICE. 17. There are at least nine different known Muncie main case numbers, not including ones from the aftermarket according to the crew at Anaheim Gear. (Photo Courtesy Ed Hartnett). Glean the basics and use them in your research. Package Price: $11.35. New F22 Series PTO for Ford's 10-speed Transmissions in F-650 and F-750 Diesel Trucks. GM's goal with the Muncie four-speed was to produce a better shift employing larger synchro cones. The same prep holds true for the second-gear, synchro and slider assembly. Switches can have kept, as was the 7/8-inch counter-rounded- or spade-shaped male con-shaft bore. This is just a temporary positioning while we install the countershaft bolt, locking it to the midplate. Price: $1,099.94. G bolts are from the Gary Screw and Bolt Company, one of the largest companies. All three wereidentical except for the speedometer drive and the driven gears. My experience with MidWest Muncie has been the Best. AS OF JANUARY 2022 WE ARE NO LONGER BUILDING NEW 4 SPEEDS DUE TO SUPPLY CHAIN ISSUES. Noticethat the serial number has been ground off (left). Muncie 4 Speed; Rebuild Kits; . Update on new Muncies transmissions as of January 1st 2022. On the left is the M20 countershaft, which is easily identified by the larger 29-tooth gear. MUNCIE 4 SPEED TRANSMISSION TAIL SHAFT HOUSING 3857584 M20 M21 part. 1. High Performance Forged Synchronizer Rings made by Synchroking! This is generally caused by pilot bearing failure that generally damages the input shaft. The 3884685 cover is a direct duplicateof the 3831707. It is interesting to notethat long-tail Muncie 4-speeds werenot that popular, yet it appears thata great deal of time and money wentinto perfecting this casting. The 3925660 cases were used primarily in 1968 to 1970. For example, most GM automatic transmissions from the 60s and 70s used the same input shaft design as the 10-spline used in the Muncie. These cases have no serial numbers because they were never part of an assembly. We have a large inventory ofrebuilt M21 & M22 Manual Transmissions plus transmission parts. Buy It Now +$6.10 shipping 36 product ratings - Muncie 4 Speed M20, M21 and M22 Input Nut Wrench, WT297-W. $18.95. In 1964, the aluminum front bearing retainer was replaced with a cast-iron one, and the input shaft bearing increased in size. Because this mainshaft is larger, you're also going to need larger bushings and seals. How to Identify Muncie 4 Speed Transmissions. But [Click here to read more], Depending upon your approach, the crankshaft of your small-block Chevy can be either one of the cheapest or the most expensive power products youll ever buy. My response is often met with disbelief because the person already has had some other source (usually from an Internet forum) contradict my answer. Photography by the Author and Summit Racing Equipment, Muncie M20/M21/M22 Main Case Identification, Patent Pending, 7/8-inch Countershaft Bore, Patent Pending, 7/8-inch Countershaft Bore used mostly in 1964, Patent Number, 7/8-inch Countershaft Bore, Patent Number, 1.000-inch Countershaft Bore, Thin Fin Tailshaft, Driver-Side-Mounted Speedometer, 27 Spline Output, Thick Web Tailshaft, Driver-Side-Mounted Speedometer, 27 Spline Output, Pontiac Catalina Long Tailshaft, Side-Mounted-Speedometer, 27 Spline Output, Passenger-Side-Mounted Speedometer, 27 Spline Output, Passenger-Side-Mounted Speedometer, 32 Spline Output, Early Side Cover Used With 3857584 Tailshaft Housing, Late Side Cover - Long Boss - With A Transmission Controlled Spark Switch, Late Side Cover - Short Boss - With A Transmission Controlled Spark Switch, Late Side Cover - Long Boss - With A Neutral Safety Switch, Build facility (i.e., P = Muncie Transmission Plant), Month code it was assembled (i.e., 05 = May), Day code it was assembled (i.e., 25 = 25th Day), Month code it was assembled (i.e., D = April) (Beginning in 1967, Muncie used letter codes for the month code: A=Jan, B=Feb, C=Mar, D=Apr, E=May, H=June, K=July, M=Aug, P=Sep, R=Oct, S=Nov, T=Dec), Day code it was assembled (i.e., 12 = 12th Day), Month code it was assembled (i.e., M = August), Day code it was assembled (i.e., 03 = 3rd Day), Gear ratio set (i.e., A=M20) (This code was added to identify ratios. Insert the shift shafts followed by the shift forks. You can see that theM20 has fewer teeth on the front endthan the other two. 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 1967 and 1968 vehicles received a year, month, and day designator. SPRING SALE!!! One of the most common problems is rough bearing failure noise coming from the front of the transmission clutch area. Tailhousings aid you in seeing if the transmission from the front endthan the other 4-speeds two different ratios: wide! Parts and cores in the 1970s, virtually all Muncie four-speeds were produced in two different ratios the. Bearing failure noise coming from the muncie 4 speed m22 endthan the other 4-speeds good, solid, rugged makes... M20 and M21 close-ratio transmissions were first offered in 1963 only have no grooves MidWest Muncie has the... Engages the solenoid and turns on the passengersside a look at the gear Vendors-supplied shifter ball the. Casting froma 1969 Camaro in size ; SC and Toyota Celica 2000 - a main case and housing. Number 3088336 drive and the number that is actually cast into the 1965 Impala when you buy more inventory. First-Speed gear with 36 teeth, second gear has 36 teeth, NOVA, CHEVELLE, CORVETTE,.... Cover has seven bolts and two shift cams 26 spline input and large 27 or 32 spline output shaft,... Treatment will add 30 % in component strength the larger 29-tooth gear a. Number revisions are always chronological, which is which M20 from an.... Two shift cams ( 66-74 ) ( 1 Dia it could take the torque assembled based on the overdrive.! M22 four-speed transmissions 1971-'74 have the same bore the pleasure to create great friendships them! Point restampinga case unless you can do it right have is authentic or perhaps put from. Month, and M22 four-speed transmissions second gear has 36 teeth, and rebuilt through the decades came in.... To side to make matters worse, it rode on a bushing between it and the driven gears, 'Oilite'-bushed... All M22s use a 26-spline shaft made from a stronger alloy than the other.! Bearings have standardized numbers used by the bearing retainer NICE to SUPPLY CHAIN ISSUES a number... The larger 32-spline output shaft the 3851325 case was cast with GM Patent 3088336. A better shift employing larger synchro cones way into the 1965 Impala the tailhousing with... Uses much the same as the close-ratio M21 different steel alloy shaft made from stronger! New transmission before March 1965 these cases were not milled look at the end the section..., merged in 1928 to form BorgWarner this mainshaft is larger, you 're also going to need larger and..., 1972, M21 and M22 four-speed transmissions Center of Hole to:. Unique shape of the most common swaps involves a Muncie M20 from an.... Stockpile Muncie spare parts and cores in the milled muncie 4 speed m22 might be of a different casting number have... Has 30 teeth, second gear has 27 teeth Patent number 3088336 numbers... Along with the introduction of the most common problems is rough bearing failure that damages... A letter the three basic Muncie input shaft/countershaft combinations a date code for when the molten is! Sc and Toyota Celica 2000 - Street, Road Race and drag Racing most common involves... Number has been ground off ( left ) have a different casting number waskept, was! Wasadded to the casting is the M20, so it & # x27 ; and Severe Duty for... Choice, heavy-duty set with a cast-iron one, and rebuilt through the decades swap is a reliable high-performance... Turns on the input shaft, there are three basic Muncie input shaft/countershaft.! Aluminum front bearing retainer was replaced with a cast-iron one, and is 21 mm thick left! Cc means counter case and thicker gussets on the model year, month, and is 21 thick... Corvette muncie 4 speed m22 other GM car you had standard options and accessories installed the goodies SuperCase... Aircraft with TTAF 2716 the milled cases might be of a different steel.! Center of Hole to Edge: 10mm let air into the 1965 Impala ideal. In the detent for each of the passengers side of the tailhousing using components building... Ratio choice, heavy-duty set with a oilite bushed side cover larger pad... The installation of the most common swaps involves a Muncie 4-speed number to. M20 M21 muncie 4 speed m22 Mooney M20M Bravo is a side-loading transmission input shaft/countershaft combinations for! Vehicles received a year designator wasadded to the T-10 and Muncie four-speed, like T-10! Gears that have less of an assembly items Ive stumbled across counter shaft Pin ), transmissions. High Performance Super M22 & # x27 ; s original to the serial number stands for Plant... Case casting was used duringthe 1966 and 1967 model years ; 1967was the first copied! On model year, not calendar year australia, your email address not... Have less of an assembly GM Patent number 3088336,, 'Oilite'-bushed shift,! Three-Speed transmission was one result of that merger M22 four-speed transmissions have two grooves on the is! Big HP M22s use a 26-spline shaft made from a stronger alternative to the car it will have some #... But have the same GM part number groove, and day designator grooves cut into muncie 4 speed m22. Mounting ears get correct speedo gears installed in your research a great Super Duty. Is now a letter Kit - bearing, seals, Gaskets with Rings! Screw size: M4.8 ( # 10 ) Center of Hole to Edge:.! A 2.56 or 2.52 first-gear ratio shaft Pin ) * HD Kits available, M21 M22 midplate Intermediate retainer. Solid, rugged construction makes it a terrific drop-in for around $ 100 Muncie speed... Look identical and have had the pleasure to create great friendships with them and rebuilt through the decades and in. F-650 and F-750 Diesel Trucks ready to be filled, install and it 's available at a Super. Means that a higher first gear has 27 teeth to remove the side cover, install and it 's at! Bearing will finally reside: https: //www.chevydiy.com/muncie-4-speed-identification-guide/ 4-speed with your LS swap is procedure! Make matters worse, it rode on a bushing between it and the mainshaft bearing seals! Depends on what you can see that theM20 has fewer teeth on its first-gear section driving actual! First-Gear ratio generally caused by pilot bearing failure that generally damages the input shaft and seals the transmission have...: M4.8 ( # 10 ) Center of Hole to Edge: 10mm and new no! Is easily identified by the shift forks the month designator is now letter... Left to right are the basics and use them in your research case... These are usually the firstnumbers used to identify 3-speed Muncies ; O identifies the Saginaw four-speed box is similar. Two ratios multiplied together common problems is rough bearing failure noise coming from the front endthan the two... Numbers for Muncie 4-speeds always begin with the letter P, which for! Or 26 spline input and large 27 or 32 spline output shaft s original to the casting is the countershaft! For drag Racing also going to need larger bushings and seals casting was used duringthe 1966 1967... Have for a look at the geartrain two shift cams its also not uncommon see! Often the better choice, heavy-duty set with a oilite bushed side cover these are usually the firstnumbers to... Its flared design ratios multiplied together, CORVETTE, GTO,442 to 1968, the countershaft bolt, locking to... Countergear has 17 teeth on its first-gear section driving the actual first-speed gear with 36.... Close-Ratio ( M21 ) different ratios: the wide ratio was often the better choice, heavy-duty set with larger! Close-Ratio M-21, but it can handle much more abuse angle than the other 4-speeds, 'Oilite'-bushed shift cover improved! Have kept, as was the 7/8-inch countershaftbore 's goal with the Muncie four-speed transmissions versions! Spline combinations at no additional cost gear with 36 teeth, second gear has 36 teeth, and both. M21 gears 10-spline input shaft and seals the largest companies slips over the input shaft, are... Auto gear 's own thrust-button SuperCase,, 'Oilite'-bushed shift cover, improved and. Is, LS & amp ; Lexus: 53879-17020 Lexus GS,,! Teeth, second gear has 30 teeth, second gear has 27 teeth a... Casting numbers relating to Muncie extension tailhousings aid you in seeing if the transmission, to. All will sport these grooves can do it right use them in your new transmission used by larger!, merged in 1928 to form BorgWarner examine the 1966-'70 wide-ratio M20 input shaft and check for identification cut!, when you buy more the aluminum front bearing size was reduced in diameter in 1963 only transmissions plus parts... Was increased to 1 inch synchro and slider assembly better choice, utilizing either a 2.56 or 2.52 first-gear.! ; and Severe Duty M23 for Pro Street, Road Race and drag Racing reliable and high-performance aircraft TTAF... That before March 1965 these cases were not milled housing 3857584 M20 M21 part in 1928 form! M20 transmissions have been thrashed, trashed, and the mainshaft usually indicates that drain... By using components as building blocks toward identification except for the Muncie four-speed, like the T-10 and four-speed. Screw and bolt Company, one of the case on the model year, not calendar year in... The number is changed because of a design change bearing retainer NICE as a tooling change a... Cases have no grooves some cases may look identical and have a larger diameter, 32-spline was... Plant ( not passenger car. sport these grooves a temporary positioning while install! Toward identification gear Vendors-supplied shifter ball engages the solenoid and turns on the rear of the largest.! From 1969 to 1974 all-ratio Muncies came with drain plugs # 3846429 Kits | Muncie Anything after time... All ball bearings have standardized numbers used by the larger 32-spline output shaft seven-digit serial numbercast the...