Need some info on this transmission. I tried google but info is scant and ambiguous. Not sure if sag or Muncie. 3 speed with universal 3 or 4 speed shifter ( Tail #-326558, GM 58, A144) (Case # GM22, 6278245, L186)(Serial # C4f 392544) (Cover # GM 395 2646, L113) (Shifter # 5030024) 10 splines in & 27 out, 5 hole bellhousing mounting, 4 5/8" bearing retainer, Case length 9 11/16', Ratio 2.85-1.49-1.00?
Saginaw 3 and 4 speed both have a 7 bolt side cover. Another quick spotting feature is the breather on the top of tail shaft housing, that gives Saginaw 3 and 4 speeds away every time.
That info would be incorrect, the trans you pictured is a Saginaw although the Muncie SM330 also has a seven bolt side cover. The difference is the Saginaw has one bolt centered on the top of the side cover while the Muncie has two bolts in-line at the top. I never had a SM330 but I just noticed online that it also has a breather on the tail shaft housing like the Saginaw so that is not an accurate spotting feature.
The 5 bolt version was used in trucks, 1970s-80s. I expect it has the large bearing retainer up front, which fits the larger hole in 68-newer truck bellhousings. The car and older truck bellhousings have a smaller hole. Muncies are aluminum, btw. I'd have to go out to the shop to look in a book to see what Chevy called it.
The HD Muncie, with a 7 bolt side cover also, as already noted above, is a cast iron transmission, as are the Saginaw's; both are also full synchro transmissions. Then there's the 55-65 Muncie 318/319 transmissions, that had a non-synchro first gear, and a 4 bolt side cover, and are generally very weak transmissions. The HD Muncie 3 speed and Saginaw 3 speeds often get confused, as they both have a 7 bolt side cover, but the bolts are arranged differently, and the HD Muncie is heavier than the Saginaw's. Both are cast iron case/extension housings. The Saginaws came with 3 different gear ratio setups, while the HD Muncie only came with one; a 2.42:1 first gear, 1.58:1 second gear, and 1:1 final drive third. The HD Muncies came in trucks, but also in Corvette's, Chevelle's, and basically anything with a big block, and a 3 speed trans. Some of the Saginaw's also came with a BW R-10 overdrive attached (the same OD that can be used to make a saginaw 4-speed with overdrive transmission). On the OP's Saginaw, with the 5 bolt bellhousing mount, unless I had the truck bellhousing also, I'd probably swap to the passenger car throwout bearing collar, and cut the 5th/top mounting bolt hole flange completely off the trans. I "thought" the 5th, top bolt mounting, was only used in the bigger trucks and in vans, but who knows for sure? I see you seem to have the gear ratios of your trans figured out. That's all I've got. I am Butch/56sedandelivery.
Here is an old thread on that trans that Jim answered back in 2010. https://www.jalopyjournal.com/forum/threads/saginaw-3-speed-help-please.531231/ I have the earlier version with 4 bolt to bellhousing and smaller od bearing retainer in my 48 and have had it in there since 1989. They are rugged and shift smooth. One thing, if you got the matching bellhousing with the trans you don't have to change the bearing retainer but that may be a tad heavy and bulky for what ever application you have.
So just had some more feedback on another website saying this is a M-16 Muncie which had a 5 bolt mount? The guy goes on to say it is also the same as an aluminum M-18 that doesnt have the 5th both hole. Fact or fiction?
Over the years, there have been MANY different 3 speed manual transmissions used by G.M.; Borg Warner 3 speeds in Buicks, HD Muncies in trucks and high horsepower cars, spindly little Muncie 318/319 in 55-65 cars/trucks (later in "some" trucks), Saginaw's in everything from Vega's to Vette's, and even a Ford made 3 speed, and a MOPAR made 3 speed with manual overdrive, have also been used in G.M. cars and trucks. Your transmission is a SAGINAW, 100%, and NO chance it's anything else. Several guys have said that it's a Saginaw; what do you want it to be? Look this up: drivetrain.com/parts-catalog/manual-transmission-rebuild-kits-and-parts/how-to-identify-chevrolet-gmc-manual-transmissions-v24. You can also do a google search for: "images of G.M. manual 3 speed transmissions" (some of these are mislabeled however). As far as your, "fact or fiction" question relates, based on that I have no real idea what this other person is talking about, I have to say FICTION. Why not just take your transmission into a transmission shop, and see what they say. If they know anything at all, they'll tell you it's a Saginaw, originally from a truck/van. There are a few transmission experts over on HotRodders.Com if you'd care to try there. I am Butch/56sedandelivery.
Butch thanks for your input...In answer to your question the only thing i want it to be is accurate. Regards
View attachment 4892592 View attachment 4892592 View attachment 4892592 74 Chevy C10 Suburban Muncie bearing retainer (GM 1 3925634) 7 bolt side cover (GM 1 3952646) main case inverted casting (GM 1 6273262) tailhousing (3968035) Build date code of a GM made Muncie is under right side of 7 bolt side cover My example of a Muncie HD (330) code is M4520A' GM used letter M so Muncie used the letter P. The letter A stands for GM shift or shifter car or truck (column or floor?) in this instance my code shows? build date of May 20th,1974 or maybe Muncie 4 speed 1975 M20? It was interesting that letter 'M' codes (M20/M21/M22) I heard alot about were the RPO (Regular Production Option) codes they don't mean Muncie they refer to the GM made gear ratio's. The last year you would get GM made Muncie's was 1974 0r 75? good info musclecardiy.com/transmissions/introduction-to-rebuilding-gmmuncie-4-speed-transmissions/
Usually the “Z” bar is held to the frame on a bolt on bracket. Unbolt the bracket and slide the Z bar (clutch linkage bellcrank) off of the ball stud. I think you will find is easier to unbolt the transmission from the bellhousing, remove it, then remove the bellhousing from the block. I think your starter can stay fastened to the engine block. Be aware, some Chevy manual transmission starters bolt to the bellhousing, so if that’s the case, it will have to come off before the bellhousing can be removed. Please don’t forget to disconnect, and isolate the NEGATIVE battery cable before you start on this project. Once the bellhousing is off, the clutch should have six bolts that hold it to the flywheel. Remove those, and pull the pressure plate and disc down, careful, they are somewhat heavy. At this point, you can access the pilot bearing. It will be pressed into the crankshaft. Truthfully, it’s likely a bronze bushing. It will have to be pulled out. There are special pullers for this, Lisle makes a tool to screw into the bushing and you pump grease from a grease gun to push the bearing out. If you have access to a large enough tap, you can tap threads into it and use a bolt to push it out as well. If it’s a roller bearing, a puller or slide hammer will have to be used. Tap the new one in with a hammer and put a little grease on the inside and reassemble. The flywheel should come down and be resurfaced if installing a new clutch. When reinstalling the clutch, you will have to have a clutch disc alignment tool to center the disc with the pilot bearing. Use new lock washers on the pressure plate and tighten the bolts evenly around the outside until they are all tight. From there, reassembly is pretty much the reverse of disassembly. Please, use some kind of jack removing and reinstalling the the transmission. You also might find it helpful to put the transmission in gear to get it to engage the splines on the clutch disc. Spin the output shaft while pushing the transmission in, obviously, when the transmission engages the splines, the output shaft will no long spin. Lastly, a very LIGHT coat of grease on the splines will help it engage. PM me if you have other questions. Andy Sent from my iPhone using The H.A.M.B. mobile app
That 5th bolt at the top was tricky just breaking them loose for the big day or maybe many PM days LOL! by the way How would I send a PM to a member?
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