4 speed manual transmission muncie
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4 speed manual transmission munciePlease help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.The SM465 can be found in Chevrolet and GMC full-size trucks, Blazers, Suburbans, among other models. Some applications beyond one-ton pickup trucks came with larger input shafts. Favored by off-road drivers, the SM465 has a very low first gear suitable for rock-crawling. The SM465 has developed a reputation as a highly durable transmission. GM literature also often referred to this as a CH465, referencing Chevrolet.The 1988-91 versions have an aluminum top with improved shift feel. The 1985 and newer versions utilize a hydraulic clutch release, replacing a mechanical linkage in older versions. A common wear factor in the form of abuse leads to having to manually hold the gear selector in third. There have been three different output shafts for pickup trucks. Early four-wheel drive was a short 10 spline, late 4WD was long 32 spline, and all two-wheel drives were 35 spline. Early 4WDs came mated to New Process 205 transfer cases. New Process 241 was used behind the 465 starting in 1989 when it replaced the New Process 208 in the V-series trucks.You can help Wikipedia by expanding it. v t e By using this site, you agree to the Terms of Use and Privacy Policy. We apologize for this inconvenience and encourage you to visit www.motortrend.com for the latest on new cars, car reviews and news, concept cars and auto show coverage, awards and much more. MOTORTREND.COM 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.Fodrea’s legacy is far-reaching, extending into popular transmissions around to this day, yet most have no idea who he was. According to Cangialosi, two companies, Borg and Beck and Warner Gear, merged in 1928 to form BorgWarner. The T-85 three-speed transmission was one result of that merger.http://www.modamoda.nl/uploads/pic_lib/bosch-maxx-2260-manual.xml
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The T-10 four-speed was an evolution of the T-85 three-speed transmission, with both of these transmissions being quite similar in appearance. 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 Saginaw four-speed box is quite similar to both the T-10 and Muncie four-speed transmissions. However, neither compares to the Muncie in terms of strength. It was a matter of economics when Chevrolet needed a four-speed manual transmission for the Corvette in the mid-1950s. 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. He tells us both the M20 wide-ratio and M21 close-ratio transmissions were first offered in 1963. The M22 Rock Crusher would come later to accommodate the heavy twist of Chevrolet’s big-blocks in the mid-1960s. The M20 and M21 transmissions produced from 1963-’74 are easy to identify in both wide- and close-ratio units. 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. Although the Muncie’s bloodline goes way back, this legendary gearbox entered service for the Chevrolet Division in 1963. 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 large-bore Muncie came into production in 1964-’65 and became the standard from then on through the end of production in 1974. 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. For 1964 and beyond, it rode on a bushing between it and the mainshaft.http://www.sensas.com/UserFiles/bosch-maxx-2450-manual.xml Cangialosi explains there were two basic mainshafts produced for the M20, M21, and M22 transmissions (see Input Shaft Identification chart). From 1963-’70, the Muncie was fitted with a 27-spline mainshaft and must have the corresponding slip yoke. For 1971-’74, a larger diameter, 32-spline mainshaft was employed along with the corresponding yoke. Because this mainshaft is larger, you’re also going to need larger bushings and seals. Keep this in mind when you’re searching for a Muncie transmission. Cangialosi tells us all M20 and M21 transmissions were produced with both 10- and 26-spline input shafts. The 26-spline input shaft came into production later in the 1970s for the M20 and M21. What you will find in your search for the right Muncie four-speed is conflicting information from different sources. Before you here are the basics of Muncie M20, M21, and M22 four-speed transmissions. Glean the basics and use them in your research. Expect to find various combinations out there because these high-performance four-speed transmissions have been thrashed, trashed, and rebuilt through the decades. You’re going to find various combinations of main cases, tailshaft housings, and side covers coupled with variations inside of each case. Pure dumb luck will lead you to a completely unmolested Muncie. 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). According to Cangialosi, the date was based on model year, not necessarily the calendar year. Of course, restorers and rebuilders will tend to re-stamp the date code to suit a particular restoration. This can add confusion to what you’ve found. Muncie transmissions also tend to get performance improvements such as a gear ratio change and stronger internal parts. This is when you have to remove the side cover to see what’s inside. Examine the input and output shafts to see if you’ve found the box you want.https://labroclub.ru/blog/02-maxima-repair-manual 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. The Muncie was originally a stronger alternative to the T-10 and Super T-10 because it could take the torque. 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. Cases are either small-bearing (1963) or large-bearing (1964-’74). The cases offer a broad range of interchangeability. Muncie transmissions from 1971-’74 have the larger 32-spline output shaft. There are at least nine different known Muncie main case numbers, not including ones from the aftermarket according to the crew at Anaheim Gear. Author and technician Paul Cangialosi tells us the original U.S. patent for the Muncie four-speed was filed on November 29, 1957, and approved May 7, 1963. Main cases manufactured prior to May 7, 1963, will say Patent Pending. Anything after that time period will say US Patent No 3088336. Remove the side cover and forks for a look at the geartrain. Removal of the front bearing cover is where disassembly begins. This frees up the geartrain. Shown here is the M20 10-spline wide-ratio input shaft and counter gear. There is also a fine-tooth 26-spline input shaft employed from 1971-’74. The 1963-’65 M20 input shaft will not have grooves. And keep in mind that not all will sport these grooves. From 1971 through the end of production in 1974, the M20 got the 26-spline input shaft. In the middle is the M21 countershaft and input shaft. On the far right is the M22 26-spline input shaft. In the 1970s, virtually all Muncie four-speeds had 26-spline input shafts. Just because you’ve found a 26-spline input shaft does not mean you’ve found an M22 input shaft, which is made of a stronger alloy. The standard 10-spline input shaft found its way into new Muncie M20 and M21 transmissions from 1971-’74.https://diving-gbdf.com/images/4-speed-manual-transmission-gear-ratios.pdf The 26-spline input shaft yields greater torque capacity via the number of teeth and greater surface area. On the right is the M22 countershaft with 27-teeth. When you have the two side-by-side it becomes obvious which is which. Note the single groove, meaning an M21 close-ratio. There were a total of six types. You can use a variety of stock and aftermarket shifters on any of the Muncie tailshaft housings. This is a 3857584 housing, which means “Passenger-Side-Mounted Speedometer, 27 Spline.” Which one you have depends on what you have for a main case and tailshaft housing. Two are early style side covers. Four are late model. On the right is the small input shaft bearing, which is 1963 only. Summit Racing Equipment inventories all kinds of cast-aluminum and steel bellhousings for the Muncie. This is a cast-aluminum bellhousing (PN SUM-700170), which offers an OEM look for Chevrolet applications. Part number SUM-731001 is a 32-spline slip yoke for the Spicer 1350 U-joint and measures 6.250-inches long. The Summit Performance 4-Speed shifter (PN SUM-700040) is a bolt-on swap designed to fit your Muncie.Aluminum Front Bearing Retainer. Small Input Bearing. Cast-Iron Bearing Retainer toward the end of 1963. Large Input Bearing. Last 3 Digits Milled Off Of Case. Large Input Bearing Large Input Bearing Large Input Bearing Large Input Bearing. Larger 32-Spline Output Shaft Some early 1969 transmissions did not have this code.We’re at the wiring and plumbing stage and we also go about tackling a ton of small tasks in preparation for getting our Monte Carlo on the road. Overdrive is the first reason you are going to add the Gear Vendors. 28.6 faster cruising speeds than you have now. Your 4.10 gears will cruise like 3.20s and your 3.55 will cruise like 2.77s. If you are normally aspirated expect 28 better fuel economy. If you have forced induction expect 50 better mpg. Performance is what the Gear Vendors is all about. This product is a very high-tech planetary overdrive. With our Auto-Launch circuit on you will leave the line in 1st and as the engine gains revs it will automatically shift clutchless to 1st-overdrive. This means you are 28 farther down the track or street before you have to clutch the car. This is key to acceleration as otherwise any manual trans car gives up big hunks of time to an automatic on the 1-2shift. Gear Vendors 1st-over ratio is only 7 hundredths different than having shifted to 2nd (not discernable and actually closer in ratio). It is not just 1st-over where you can use this clutchless shift. You can be in 2nd just boulevard cruising and show off by stepping on the throttle and hitting the Gear Vendors button on your sifter for 2nd-over which is identical (exact same ratio) as having shifted to 3rd but only clutchless (and with a nice bark of the tires). Most street guys will just grab a clutchless gear at whatever moment they start accelerating and then progress up through the gear box leaving the overdrive on so that each gear is just now up a step. The bracket racers and serious street guys will flip the 3-4 side cover lever over so they can easily have two clutchless shifts in the A? mile with just one clutch depression. Flipping the 3-4 cover lever over lets them grab with a straight pull back because it moves 3rd to the 4th gear position on the pattern. Just awesome performance gains greater than a full second on the watch, increased mph and far more performance than any 5spd or 6spd tranny swap. So you get a 5th gear overdrive and at least one clutchless shiftto be used at any moment (we ship the kit with our 6speed car badges) and a huge performance gain plus get to retain your period correct transmission in the car and get the worlds strongest overdrive trans. Since your Muncie or BorgWarner is stronger than any non-race 5 or 6 speed, the Gear Vendors is just he right way to get overdrive in your GM manual performance car. For more details on this subject click here. If you take a few moments to study the gear chart for your transmission and rear end ratio combination you will see why this product is so popular. The Final Drive Ratio shows you how many times the engine turns for one complete turn of the tires. Gears are multiplier of torque. Close ratio gearing lets us work both the torque and rpm side of this equation for big gains in HP and performance. Our payment security system encrypts your information during transmission. We don’t share your credit card details with third-party sellers, and we don’t sell your information to others. Used: Like NewSitting on shelf.Something we hope you'll especially enjoy: FBA items qualify for FREE Shipping and Amazon Prime. Learn more about the program. Please try again.Please try again.Please try your request again later. The Muncie was the top high-performance manual transmission General Motors offered in its muscle cars of the 1960s and early 1970s. It was installed in the Camaro, Chevelle, Buick GS, Pontiac GTO, Olds Cutlass, and many other classic cars. Many owners want to retain the original transmission in their classic cars to maintain their value. Transmission expert and veteran author Paul Cangialosi has created an indispensable reference to Muncie 4-speeds that guides you through each crucial stage of the rebuild process. Comprehensive ID information is provided, so you can positively identify the cases, shafts, and related parts. It discusses available models, parts options, and gearbox cases. Most important, it shows how to completely disassemble the gearbox, identify wear and damage, select the best parts, and complete the rebuild. It also explains how to choose the ideal gear ratio for a particular application. Various high-performance and racing setups are also shown, including essential modifications, gun drilling the shafts, cutting down the gears to remove weight, and achieving race-specific clearances. Muncie 4-speeds need rebuilding after many miles of service and extreme use. In addition, when a muscle car owner builds a high-performance engine that far exceeds stock horsepower, a stronger high-performance transmission must be built to accommodate this torque and horsepower increase. No other book goes into this much detail on the identification of the Muncie 4-speed, available parts, selection of gear ratios, and the rebuild process. Then you can start reading Kindle books on your smartphone, tablet, or computer - no Kindle device required. In order to navigate out of this carousel please use your heading shortcut key to navigate to the next or previous heading. In order to navigate out of this carousel please use your heading shortcut key to navigate to the next or previous heading. Register a free business account Available models, parts options, and gearbox cases are thoroughly covered. Full color step-by-step photography shows how to completely disassemble the gearbox, identify wear and damage, select the best parts, and complete the rebuild. You learn how to choose the ideal gear ratio for a particular application. It also includes a complete parts guide with illustrations. No other book goes into this much detail on the identification of the Muncie 4-speed, available parts, selection of gear ratios, and the rebuild process. Add this book to your library today!He first started working on cars at the age of 12 and his automotive passions have burned bright ever since. He has pursued his passion for manual transmissions for nearly 30 years. Today, Cangialosi's businesses offer 12 different rebuild kits and 6 new transmissions, as well as rebuilding, fabricating, and design services for high-performance manual transmissions.If you are a seller for this product, would you like to suggest updates through seller support ? Amazon calculates a product’s star ratings based on a machine learned model instead of a raw data average. The model takes into account factors including the age of a rating, whether the ratings are from verified purchasers, and factors that establish reviewer trustworthiness. Please try again later. Navin R Johnson 5.0 out of 5 stars This book quite well written so that even a modestly skilled mechanic can get a grip on one of the most complicated tasks they may ever have to do. I had some problems with my M20 recently so I started to try and get some experienced info on the internet with very little help. Mostly incorrect and or bad info is out there and this book has already answered a couple of major questions on what parts to order. In my case just because what parts came out of the transmission aren't necessarily right parts in the first place. Earlier replacement parts were put in that were incorrect. I had a non thrust loaded max capacity front input bearing in my M20. The cage had separated which was chewed up and all the balls were loose and even the inner and outer race were cracked. I almost ordered and put in the same non-thrust loaded bearing that was incorrectly put in. This book explained the differences with the styles of bearings and which ones to use for your type of Muncie. And oh yeah, one more thing. It even has a great section on how to break down, clean and rebuild your Hurst shifter. I almost never write reviews but this book and guy deserves the good credit here. Can't thank you enough Paul for this great book!! CheersThe Muncie M-21. I have one stuck behind a 350 sitting in a 1970 Chevelle in the garage, sitting next to a 1969 El Camino with a 350 backed by an automatic. Everyone seems to think they can fix it, but nobody including myself is up to the task.They are still in business but you have to order parts on the phone. They delivered quality american and italian made parts for the same price as the chinese knockoffs on the net. Book has good quality photos and is clearly written. Didn't use the high performance sections but read through and they seemed like they were top notch!Great info on different generations as well. Must have book for anyone with a Muncie fitted car whether you work on it yourself or just want to know the details about the transmission. I highly recommend it.The book gives lots of good information on all kinds of stuff about Muncies, and the step by step disassembly and reassembly portion is great and has good pictures. If you buy a Muncie rebuild kit online it's plug and play with the help of this book.The only thing I wish it had. The only thing I wish it had was alternate descriptions options for reassembly. My front bearing would not just slip fit into the case. I had to use a press...and get creative with how to get it in without damaging the bearing.Paul has no problem pointing out some of the garbage information out there. Plus if you have any questions you can post to his Facebook page and the crazy guy will answer (Last time I posted at 10 pm Alaska time, he answered in 30 minutes which would be 3:30 am Jupiter Florida time. ANd the photos are very informative. I was able to rebuild the wifes M-21 in her 1970 Firebird in no time at all (first time even cracking a manual trans open.)Got it immediately and very handy to use. I checked each stel as I proceeded with the rebuild. If you need it, technical support is just an email or phone call away.A oot of clear pictures make it easy to understand. So far I have disassembled the gearbox but I'm confident that I can assemble it.Sorry, we failed to record your vote. Please try again Sorry, we failed to record your vote. Please try again I found the author on You Tube and liked what he had to say and how he presented the subject of rebuilding, so ordered the book to have it at my side while tearing it down. I was very pleased with the content of the book and the fact that it includes many extras such as how to identify your particular Munci, as there were a few. Pictures and explanations are excellent. Great book!Sorry, we failed to record your vote. Please try again Copre tutti i Muncie a 4 marce. Consigliato.Sorry, we failed to record your vote. Please try again So ein Buch ein mit in die Garage nehmen ist allerdings einfacher. Das Buch hat mir beim Entschlu?eln der Gehausenummern und bei dem einstellen vom Schaltgestange geholfen. Uberholen muss ich das Getriebe zum Gluck noch nicht.Sorry, we failed to record your vote. Please try again. The Muncie design has roots going back to 1935. I took the time to research the patent number that is cast into most Muncie main cases. It is U.S. Patent Number 3,088,336 (see Appendix). You will see that James W. Fodrea designed the patent; no other engineers are listed. If you look closely, you’ll see that the patent drawings look nothing like the Muncie 4-speed but rather like the BorgWarner T10. Therefore, the Muncie patent is basically a design for the layout of a 4-speed transmission. This “layout” is a 4-speed transmission with four forward gear ratios in the main case, a midplate bearing support, and a reverse gearset in the extension housing. For a comprehensive guide on this entire subject you can visit this link: It’s a standard M20 model. They designed a 3-speed transmission, the T85, which was originally used in the 1935 Chrysler Airflow. It was used right up to 1971 in the Ford Pickup F100 with an overdrive. The T10 shares the same case design, gear centers, and 3-4 synchronizer as the T85. The cases have a distinctive similar size, shape, and cover-bolt pattern. Fodrea was the GM engineer whose name is listed on the design patent for the Muncie. Although he is seen with a 1957 Corvette, which came with a T10 4-speed, the design of the T10 and Muncie share the same features. The center gear is from a BorgWarner T85 3-speed. The lower gear is the latest version of the early T10 and the upper is the Muncie M22. Note how the Muncie gear is physically longer than the T10. The reason for these design changes was simply to meet the demand for increased torque capacity His brilliant and well-thought-out idea was to make it into a 4-speed. It’s important to understand that in 1956 General Motors didn’t have the money for the Corvette program. Zora Arkus-Duntov wanted to use the design of General Motors’ employee James Fodrea. BorgWarner was probably the foremost manual transmission manufacturer at the time, and basically wrote the book on manual transmission design. (They are credited with hundreds of manual transmission patents.) It is therefore no surprise that a decision was made for BorgWarner to manufacture this 4-speed transmission based on the GM concept drawings and Fodrea’s patent. It was a very logical decision: Tooling costs would be minimal because hobs, castings, and certain components could be used from the T85 platform. This would be the fastest and most cost-effective way to put a 4-speed into a Corvette with very little risk. Many Corvette restoration books share the common misconception that the 4-speed T10 and Muncie are two separate entities. They are not; the Muncie evolved from the T10. Whether it was a series of lucky choices, or happy accidents, the 1957 design allowed for improvements. Other muscle car transmissions of that era, such as the Ford Toploader and Mopar A833, left no room for improvements because of the layout and initial design of their geartrains. The Super T10 was a later-version design of the T10. The center gear is from an early T10 and on the right is an M21 Muncie gear. All of these gears have the same number of clutch teeth: 36. Notice that the Muncie synchro cone is larger in diameter for improved stopping power. In 2012, Motive Gear acquired Richmond Gear and they are still manufacturing the Super T10 today. Several NASCAR transmissions, such as the G-Force T101, are also T10-based. The Muncie saw many improvements during its 10-year production run with General Motors. Auto Gear Equipment (AGE) currently produces Muncie replacement parts as well as new replacement transmissions. Auto Gear sells them directly and also through approved distributors. Auto Gear’s “Syracuse 4-speed” is a Muncie on steroids. It appears that BorgWarner had an exclusivity contract with General Motors until 1960. This was the first year that the T10 was used in the Ford Galaxie and Fairlane. Soon after, Chrysler and American Motors began using the T10. With the power levels increasing in GM muscle cars the power capacity of the T10 also needed to increase. Its concept and design are identical to the Muncie’s. Both were derived from the same U.S. patent. Your can see that the layout of the geartrain is identical to the ST10’s. All gears and synchronizers are in the same position. Notice how the angle of the M22 gears is much straighter than on the ST10. The noise level increased because of this angle, giving the M22 the nickname “RockCrusher.” First was to revamp the T10 to handle more power. Second was the direct benefit of the increased sales volume of the 4-speed GM muscle car market. The third reason was increased T10 royalty benefits. When designing transmissions you have to remember that as vehicles change dynamically (increased horsepower, weight, or gas mileage requirements) the transmission also has to change. Because the Muncie was well engineered, there was room for improvement to the base design. Modern automation gives companies the ability to store incredible amounts of data; it’s much easier to track changes. Today’s VINs (vehicle identification numbers) are even bar coded. A service technician can use a scanner to find a VIN, and any known service issues are easily found. I’m not a fan of these but I do understand their importance. I do not like them because, for the most part, they are admitting defects to a design. They fix it if there is a complaint but do not order a recall. Recalls are bad publicity, so it’s easier to fix the problem silently rather than risk sales. The problem is that some cars just aren’t driven very often. The service issues crop up after the warranty period has expired and the owner is left to pay for a repair on something that was defective in the first place. It had three major service issues affecting 1984 and 1985 models. I had the bulletins, but most of these service issues happened after the warranty period ended. These proved to be very weak and were replaced by a cast-iron retainer (604932). Both of these retainers are now extremely rare. You also need to remember that all record keeping was done manually and sometimes the changes were left undocumented. It is often very difficult to decipher what part numbers actually match the part you may need because the GM parts books have discrepancies. It had a small 6207-style front bearing and an aluminum front bearing retainer. This retainer was upgraded to cast iron by the end of the 1963 run. The 3831704 cast main case is unique because the front bore is smaller than it is on later Muncies. The first-speed gear rode directly on the mainshaft. A snap ring retained the first and second synchronizer assembly on the mainshaft. The first-speed gear had a smaller bore diameter as well as a recess in the bore to clear the synchronizer retaining snap ring. It had a thrust washer behind first gear that floated on the rear bearing inner race. It is from a Saginaw 3-speed, casting number 591620. It can be used as an adapter-bearing retainer. It was an old trick to enable small-retainer transmissions to correctly pilot to largeretainer-bore bellhousings. If you attach a small-retainer transmission to a large-bore bellhousing the transmission is not piloted correctly. Typically, the front bearings shatter and input shafts break teeth, usually at the end if this mistake is made. This adapter retainer can be used to attach a 1963 Muncie to a later bellhousing. You can also turn down the outside diameter on a lathe to replace the rare 3790278 or 604932 retainers. For some reason, the unique 1963-only items were still used in exploded-view illustrations, which confused many rebuilders into the early 1970s. An original 1963 shaft is shown at right while a rare BorgWarner replacement shaft is at left; it has an added oil cavity on the first-gear section. Notice that these shafts only have enough room for the speedometer drivegear to press onto them in one place. This means that they can only be used with extension housings that have a driver-side speedometer gear. Both the M20 wide-ratio and M21 close-ratio transmissions were offered. These were the only ratios ever offered from General Motors for the Muncie 4-speed: The far left gear is a 1963 type that has the recess for the 1-2 synchronizer snap ring and a smaller bore. The middle gear is the laterstyle original-equipment late-1964 to 1974 gear. On the right is an aftermarket gear made in Taiwan. The first was the introduction of a larger-diameter front bearing that meant a new case casting and larger-diameter front bearing retainer were necessary. The second was that the first-speed gear now rode on a bushing that was press-fit onto the mainshaft. It stopped against the first and second synchronizer assembly, thereby eliminating the need for the assembly to have a retaining snap ring. Because the bushing was subsequently retained by the rear bearing, the synchronizer could not go anywhere. The first-gear thrust washer was eliminated and the gear was designed to have a thrust surface that ran against the rear bearing’s inner race. The first was added strength. Whenever you have a snap-ring groove between a flow of power you have a potential stress riser on the shaft. Because the slider engages first gear across the snap-ring groove, a huge stress riser develops that leads to broken mainshafts. First gear also had a tendency to seize to the mainshaft.