(1: Chevrolet, 8: 1968, L: Van Nuys, CA, 165790: last 6 digits of VIN). A=M20 B=M21, C=M22). 18L165790 Muncie (left) Saginaw A manual transmission requires the driver to switch gears manually. Many enthusiasts feel that for a car to be a true muscle car it must have a four-speed transmission. Jointly developed by Chevy and Buick, it is also known as the CBC (Chevrolet-Buick combined) 350. A typical Saginaw assembly date stamp would be S313 indicating Saginaw trans produced March 13. If a car came with an axle ratio of 3.73 (or numerically higher), it usually came with a close-ratio transmission. The code interpretation is (Cleaveland Powerglide, January 23rd, Night shift). Some exceptions include the 1970 with either the SS396 or SS454, the 1971 and 1972 SS with the 454 engine where the H.D. They are found primarily in GM and Chevrolet trucks, Blazers, Suburbans and many other models falling under the 1/4-ton to 1-1/2-ton platforms. On the THM700-R4 the VIN is either stamped onto a boss behind the bellhousing flange on the passenger side, just above the pan on the drivers side, or just behind the governor cover, stamped vertically where the case meets the tailshaft housing. Thank you Monster Transmission. Look at the floorboards, and if there are only two pedals, the car is automatic. Responding to market demand for a three-speed automatic, The Turbo-Hydramatic 350 was introduced in 1969 as a replacement to the Powerglide in Chevrolet cars and trucks with six-cylinder engines or low-horsepower V8 engines. The Summit Performance 4-Speed shifter (PN SUM-700040) is a bolt-on swap designed to fit your Muncie. Serif is a seasoned automotive enthusiast with a passion for cars. This list includes some GM transmissions. thoughts? The casting number 3925660 denotes this as a 1968 - 1970 Muncie with a 1-inch cluster shaft. Powered by UBB.threads PHP Forum Software 7.7.5. While the big-block vs. small-block variable is one that has two groups of passionatefollowers, the other reflects the way in which the driver selects transmission gears. 2.1Date codes 3GM transmissions, including Muncie M20, M21, M22 4Automatic transmissions 4.1AMC automatic transmissions, 1972-'06 4.2AMC automatic transmissions, 1955-'71 4.3Jeep automatic transmissions, 1971-back 4.4Transmission dimensions 4.4.1Ford 4.4.2MOPAR 4.5Ford automatic transmissions 4.5.13-speed identification 4.5.24-speed identification Chevy Hardcore NEWSLETTER - SIGN UP FREE! They created a standardized naming system across the product line and changed the name of the Turbo 400 to 3L80. The M22 Rock Crusher would come later to accommodate the heavy twist of Chevrolet's big-blocks in the mid-1960s. In order to correctly identify a Muncie four-speed transmission, several visual clues are needed, and those cues involve the casting numbers on the case, side cover, and tailshaft. 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 transmission pan is a wealth of knowledge because it has various inscriptions concerning the transmission. But the other numbers don't match the extension or sidecover casting numbers. This page covers automatic trannies. Also, there were some input shafts produced by the aftermarket and General Motors that have no identifying rings on them. 11. My question is will this direct swap to a '81 with the 3 speed saginaw? The source serial number is from the CAR the transmission originally went into, NOT the assembly plant. 19. These days, the tag looks like P8E17 (Powerglide= type, 8= 1988, E= month, 17th= day). When repairing or restoring your Chevrolet car or truck, identifying the transmission youre running is a key element to avoid the automotive version of quicksand. Did you know that there are various models that were used in various cars? FORD (336) BORG-WARNER T-10, GM AS-3 (410) *MUNCIE Shaft Identification:. This was used in A-body and F-body cars and Corvettes into the early 80s. From 1950-1973, most GM divisions used the iconic Powerglide transmission. All rights belong to the entity responsible for the trademark or copyright. Outside that, you can push in your clutch and hold the brake. Due to this, the box tends to The 400 transmission has a main case of cast-aluminum alloy with a length of 24-3/8-inches long. The easiest way is by knowing the construction of each unit, and the differences are obvious. If you do happen to stumble across Chevy four-speed at a swap meet, do you know what you are actually looking at? It is widely known as one of the best automatic transmissions ever built. a usually four digit letter/number combination separated like this: X XX X. Generally able to handle up to 400 foot pounds of torque. The number of bolts fastened to the pan is a way of being sure of the transmission system. Transmission block casting number R 7 T 28 GM number 3890564 Martinius. You can check online auto repair websites, as some have free decoders. General Motors has produced a myriad of versions of its fabled automatic transmissions over the years, although three models make up the bulk of pre-ECM GM slushboxes; the. Now, lets explore GM transmission identification, the different methods, and more. These grooves were cut into the input shaft so assembly line workers at the plant could easily identify which input shaft should be installed in a particular unit. 9. In the middle is the M21 countershaft and input shaft. The easiest method of GM automatic transmission identification is to examine the transmission pan. The Fora platform includes forum software by XenForo. 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. flashlight. Pre-67 Example: C213N (C = Cleveland Powerglide, February 13, Night Shift) Ford didnt offer its automatic transmission until 1951, and Mopar buyers had to wait until 1954. We're transmission experts, recognized by some of the greatest and most notable technicians in the automotive industry. possible Letters for the last ones are explained in the chart below. Another quick way to identify a Turbo 400 is to look at the kick-down mechanism. If youre unaware, the production sequence is the last six numbers of your VIN. Shown here is the M20 10-spline wide-ratio input shaft and counter gear. Use the following information to compare physical description of your Chevrolet or GMC manual transmission in order to identify what model transmission is, MySpace !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); Has the casting # of 3925656. and will have no numbers stamped on that deck. The length of the unit can also tell you a few things. . The M-20 wide ratio, the M-21 close ratio, and the "Extra heavy numbers here that I can prove, so this is a short list. Not a T10 (1304 series); If its iron and has all three shift levers on the side cover, its a Saginaw. Check the car flooring, and if theres a clutch pedal, the transmission is manual. Clean the area thoroughly and use a nice bright flashlight. 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. The Turbo 375 was a version of the transmission used from 1972 through 1976, in small displacement cars. V8 engines included 283 and 327. Main case casting numbers (when looking at the passenger side these numbers are upside down) 6273262, tail shaft housing casting numbers 3968035, Shifter cover casting numbers GM1 3952646. The Head Casting number is located outside of the Valve Cover in plain site on the Drivers Side. 2023 Power Automedia. GM Turbo 2004R (2004R Transmission) Overdrive Transmission. Notice: Any comments posted herein do not necessarily reflect the official position of the VCCA. All transmissions with a 26-spline input shaft used a 32-spline output shaft, and all those with a 10-spline input shaft were paired with a 27-spline output shaft. Depending on how you ordered your muscle car in the 60s and early 70s, you might have even benefitted from the famous Muncie transmission. Here's another view of the M22's input shaft and countershaft. Please click Accept Cookies to continue to use the site. Main cases manufactured prior to May 7, 1963, will say Patent Pending. They are notoriously If you dont know where to check, the transmission usually stays around the area of the rear tires. As long as you have the correct transmission shift levers, it should't be much to convert to the later trans, but I'd probably start with the Saginaw, given the choice. To add a little confusion to the mix, there were Borg-Warner Transmissions that feature aluminum cases and cast-iron side covers. When you have the two side-by-side it becomes obvious which is which. Transmission Identification & Decoding. When properly identifying a Saginaw transmission, the casting numbers are a surefire way to know for certain what youre looking at. There are no members with birthdays on this day. It was a matter of economics when Chevrolet needed a four-speed manual transmission for the Corvette in the mid-1950s. When you find a used four speed, a Saginaw and Borg Warner transmission will likely be flash rusted because of the cast-iron construction. case. This is what "The World's Best Chevrolet Club" is all about! if (theYear < 1900) By 1963, the General had developed and worked with the Saginaw Corporation to develop a proprietary Chevy four-speed (based on components used in the Borg-Warner transmission). 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. Transmissions available: 3 Speed manual, 3 Speed manual with overdrive on 1/2 ton only, 4 Speed manual and two automatics; Powerglide and Turbo Hydra-matic. Use the owners manual to find information such as the transmission pan length, shape, and more. This is the M21 10-spline input shaft with a single groove and the applicable 27/22/19/17-tooth countershaft. JavaScript is disabled. 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. These numbers can be found on the transmission case, and the first letter in this series of numbers is going to tell you exactly which Saginaw transmission you are looking at. You need to look . General Motors has variety when it comes to automatic transmissions, and some of them have different pan shapes. 3952645 shows up as the sidecover casting number for the 1972 Saginaw 3 speed. Need help to decode Saginaw 4 speed transmission. Images courtesy chevelles.com. However, finding one of these transmissions now at a swap meet or salvage yard is getting harder and harder. The constants in decoding the transmission ID number are the date the transmission was produced. Slide under the car and locate the transmission. Some transmissions will have a code stamped onto them while others have a tag riveted to the case. 1965 and Newer. Typical Turbo 350 fluid pan. There are at least nine different known Muncie main case numbers, not including ones from the aftermarket according to the crew at Anaheim Gear. If it is still attached, the ID can be found in several places on the transmission: If youre under a car trying to read this, it can be tough. Gm manual transmission identification numbers. CAUTION: This transmission closely resembles 343 Saginaw. This is an M21 with 10-spline input shaft and cast-iron bearing retainer. The Casting Numbers to the right are found just below and to the right of the Distributor on the passenger side. It functions correctly. S = Saginaw 3-speed A = 68/69 L6 Torque-Drive K = McKinnon 3-speed C = Cleveland Powerglide . THM250 - Used in small 4 cylinder cars (Vega, Sunbird, Monza) from 1973 to 1981 and some Nova/Camaro/Chevelle 6 cylinders in 1974 & 75. There is also a fine-tooth 26-spline input shaft employed from 1971-'74. Summit Racing Equipment inventories all kinds of cast-aluminum and steel bellhousings for the Muncie. The two transmission systems manual and automatic, have different working principles. 1991 and Newer very hard to read and often people make the mistake of thinking a '3' is an '8'. The 17-character number is a form of code that identifies the vehicle's specifications. The M-22 has "straight cut" gears. M38 Standard Turbo 350 manufactured from 1976 to 1981. Some of these methods are: All the above-listed methods are dependable ways of identifying a cars transmission. FIRST TRANSMISSION. It was phased out of use and superseded by GMs 700R4 starting in 1982. 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. When introduced in upper-level Chevrolet models in 1950, the Powerglide represented the first automatic transmission offered by the Big Three. Not only were they both popular transmissions in muscle cars and Corvettes, but many were even used after the muscle car era. With an old GM 4-speed manual, you have to observe the transmission system side profile. Do you know how to tell the difference between a Saginaw, a T10, and a Muncie four-speed? Also, the chances of older cars having an intact manual are slim. These classic GM models have different complex applications under manual transmission and automatic transmission. The Muncie has probably been the most popular transmission among the hot rodding set since its inception in 1963. Show More Show Less. If the car has high-performance upgrades that substantially raise the engines torque output above 300 to 350 lb./ft. Post-67 Example: P9E03 (P = TYPE, 9 = year (1969), E = Month, 03 = Day of Month), Month code: Please check your browser settings or contact your system administrator. Its case is essentially smooth. Identify the Transmission You Have. While the M21 and M22 did have the same gear ratios, the M22 did utilize a cluster gear with the gear teeth having different tooth angles. Apart from numbers, General Motors transmission ID tag has codes. - Date Casting Codes Vehicles leaving the factory with an axle ratio of 3.55 and numerically lower gears, typically incorporated a wide-ratio transmission. 4L60 - Early 1990's saw the 700R4 renamed to the 4L60, and "electronic" models were named 4L60E. box FWIW. Differentiating is easy, as the Muncie has seven bolts holding the side cover, and the Borg-Warner uses nine. Randy Bolig has been working on cars and has been involved in the hobby ever since he bought his first car when he was only 14 years old. The easiest way of knowing your GM transmission is by using a VIN decoder. Last edited: Dec 16, 2012. . It is easy to determine whether you have an early or later model Muncie four-speed transmission by the way the transmissions linkage arms are attached. It is a cast iron case tranny with either a 2.85 first gear or a 2.54 first gear. How to identify and decode chevrolet manual transmissions. Whether youre trying to repair your transmission or rebuilding a project car, its crucial to identify the transmission type. Used on large displacement, high torque engines and engines with towing packages. From complete engines, to torque converters to Monster in a Box, we've got all your HP needs covered. Input has 3 rings so it should have the 3.50 first gear. Pre-1969 Muncies use a stud and nut at the indicated attachment point, while 1969 and later boltPRE 69' MUNCIE & ALL 69' & LATER MUNCIEMuncies use a bolt as illustrated on the right.BORG-WARNER SHAFTSTRANS ID 452,453 MUNCIE M-22 (453)TRANS ID 451 3925656 is the casting number for the saginaw used in 68-75 at least. The Turbo 400 was GM's heavy-duty three-speed transmission used from 1964 to 1990. Chevy Automatic Transmission Description & Usage According to Cangialosi, two companies, Borg and Beck and Warner Gear, merged in 1928 to form BorgWarner. 14. This machined flat area has serial numbers The M20 and M21 used a gearset with a more angled tooth design on each gear (left). item 2 Restored GM Saginaw 3 Speed Manual Transmission 10 x 27 Select From 4 Ratios Restored GM Saginaw 3 Speed Manual Transmission 10 x 27 Select From 4 Ratios. (AODE & 4R70W). Clean the area thoroughly and use a nice bright There are a couple of different debates that typically occur when a bunch of car guys get together. X3845157 GM. This patent number, according to Cangialosi, can be found cast into most Muncie four-speed main cases. There are not too many gearboxes that can make that claim. It is identified easiest by its 375-THM designation cast in the underside of the tail housing. 2nd and 3rd row seats were optional. H = Muncie / 3-speed K = McKinnon / 3-speed M = Muncie / 3-speed N = Muncie / 4-speed O = Saginaw / Overdrive P = Muncie / 4-speed M20 . 691747 OR 591747. Build your own custom newsletter with the content you love from Chevy Hardcore, directly to your inbox, absolutely FREE! Each number in the 17-digit VIN represents specific information about a vehicle. Of course, that was many years ago. 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. Although the Muncie's bloodline goes way back, this legendary gearbox entered service for the Chevrolet Division in 1963. You can use things like the pan material, length, and shape to identify it. On the right is the M22 countershaft with 27-teeth. Next, carefully raise the vehicle with a jack. Muncie transmissions from 1971-'74 have the larger 32-spline output shaft. The SM465 is an outstanding, heavy-duty truck transmission designed and used in , 3/4 and 1+ ton trucks. Note partial VIN stamped at the bottom. 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 So now that we have given you some insight into identifying the Chevy four-speed transmission, the next time you are scouring the swap meets or local Craigslist ad, youll have a better understanding of what you are looking at, and youll get exactly what you want. $750.00 The best way to ID the transmission is to count teeth. While casting numbers are a definite guideline for identification, a quick, somewhat accurate way to quickly identify Muncie transmissions involves the input shafts. Effective October 21, 1968, an additional letter was added to the plant prefix number to help identify the gear ratios in Muncie transmissions. From 1967 on, the ID number contained the transmission type or plant prefix, Date (coded below), and a shift code. If the case, side cover, and tail housings are made solely of aluminum, well my friend, that would be a Muncie. You can find the exact transmission you have. Casting Number Year Notes, 3831704 1963 7/8-inch cluster, small bearing, 3839606 1963 1964 7/8-inch cluster, 3851325 1964 1965 7/8-inch cluster, 3864848 1965 7/8-inch cluster, 3885010 1965 1967 1-inch cluster, 3925660 1968 1970 1-inch cluster, 3925661 1970 1974 1-inch cluster, Casting Year Notes, 3831731 1963 Thin fin tailshaft, drivers side speedometer, 27 spline, 3846429 1963 Thin fin tailshaft, drivers side speedometer, 27 spline, 3846429 1963 1965 Thick fintailshaft, drivers side speedometer, 27 spline, 9779246 1964 1965 Pontiac Catalina long tailshaft, passengers side speedometer, 27 spline, 3857584 1966 1970 Passengers side speedometer, 27 spline, 3978764 1970 1974 Passengers side speedometer, 32 spline. For a better experience, please enable JavaScript in your browser before proceeding. The 4L80E would be the "electronic" model. This includes but is not limited to Ford, Chevrolet, General Motors, Dodge, Mopar, or any other trademarked or copywritten content. Looking for a Muncie shifter engineered to fit within your budget? severely powerful (high torque) big-block engines. In the early 90s, GM rebranded all of its transmissions. 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. //
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