[wolfdaddyss454]

I have a 71 Chevelle SS 454 4spd M22 so Im told. It has never given me any trouble and I'd like to install the same in my 71 SS454 Elcamino in stead of the 400 Th it now has. I've seen Mucie Transmissions at swap meets taged M22 but sinse Ive not had any trouble with my M22 I'm not famillar with what to look for in ways of wear and problem areas to look for or how to be sure if it is a M22 or M21 Ive been told a M22 has fine spines where others do not. What Im asking? Can any body tell me?

1 What to look for in wear?
2 What to look for in Identifing a Muncie?
3 What are problem areas?
4 Does anyone want to sell a complete setup pedal, bellhousing, flywheel, chutch,
pressure plate, clutch linkage,?


THANKS FOR YOURE SUPPORT!

 

[Wes V]

Go to your local Barnes & Noble and get one of the many books that cover the transmission you are interested in. Read it and add "post-it's" to tag the pages that will help you identify the trans.

BRING the book with you when you go to swap meets!! (it helps if it's got a lot of greasy finger prints on it for effect!)

BRING a socket wrench and socket so that you can remove the side plate and check out the condition of the gears. If the person doesn't want the side plate removed, offer to give him 2 bucks to cover the cost of a new gasket, if he still doesn't want you to remove the plate, WALK AWAY!

As for all the "pedal" stuff, you can get them through Original Parts Group or go the junk yard route. Don't forget to look at ALL the "A" bodys available. Pedals don't know if the car originally had a three speed, although the bell-crank may be different if a 6 cylinder engine. (I once got all the pedal assembly and linkage parts for a 69 Camaro out of a 70 Nova with three speed)

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Wes. Vann
Technical Reference section
Gold Member #5

 

[ccrider]

wolfdaddyss454-
Here are some links for additional info related to Muncies -
www.stc.net/~iracez28/transid.html
www.gearzone.net
The gearzone article is very good with pictures of an M-22 compared to M-20 gear set. Also, if you do a search on "muncies" here at "Chevelle Tech" you will find lots of information related to Muncies. Finally, chevelle.com member Dzauto is very knowledeable about Muncies and was a big help to me.

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ccrider
Member #:267
ACES Member #:3379
66 Chevelle SS

[This message has been edited by ccrider (edited 11-15-99).]

[This message has been edited by ccrider (edited 11-15-99).]

 

[DZAUTO]

Wolf,
First of all, to check externally for an M-22, you need to find the stamped date code which is a combination of letters-numbers on the main case (usually at the rear side or top of the main case). A Muncie date code will start with a P-for Muncie, a number for the year, such as a 1 for your 71, then a letter for the month, a number for the day of the month, AND LAST, A LETTER, (starting in 68) A,B or C. A for M-20, B for M-21 and C for M-22. As an example, let's say your 71 M-22 was made on Mar 22, 1971. The date code for it would be P1C22C. Muncie-71-Mar-22-M22. That last C designates M-22 and it is the only external way to tell if it is (or was) an M-22. Now, if at sometime in its life it broke and gears were too expensive to replace it may have been converted to an M-20 or M-21. SO, THE ONLY WAY TO KNOW FOR SURE IF A MUNCIE IS AN M-22 IS TO OPEN IT UP AND LOOK AT THE ANGLE OF THE GEAR TEETH. Go to Gearzone for a good comparison of the difference.

To identify a Muncie, look at the side cover. It has 7 bolts and the top center bolt hole is raised above the straight surface of the top of the side cover. A Borg Warner Super T-10 has 9 bolts and the top edge of the side cover is straight.

ALL 63-70 Muncies (except '70 M-22)had a 10 spline input and a 27 spline (turbo 350 size) output shaft. The 1970 only M-22 and ALL 71-74 Muncies had the fine 26 spline input and big 32 spline (turbo 400 size) output shaft. DO NOT LET ANYONE CONVINCE YOU THAT A FINE SPLINE INPUT OR A LARGE OUT PUT SHAFT MEANS IT IS AN M-22! First, look for the "C" at the end of the date code. If there is a C, then the only way to verify is to remove the side cover as above. If there is no C in the date code or it has an A or B, then it is unlikely that anyone has converted an M-20 or 21 to an M-22 (except me).

Some Muncies do and some do not have a ring(s) around the input splines.
GENERALLY SPEAKING:
63-65 M20-no ring
63-74 M21-1 ring
66-74 M20-2 rings
M22-no rings
Any GM replacement input shaft-no rings(?)

Problems: If it ain't broke, don't fix it. An M-22 is supposed to whine louder than an M-20-21.
If it grinds or doesn't slip into gear easily, it probably needs new brass syncro rings.
If it leaks oil around the front of the cluster shaft, the hole in the case is oversize (worn) and needs to be repaired with a bushing.
If it buzzes and vibrates through the shifter handle going down the road, the rear main bearing is probably bad.
If it goes click click click, there is probably a (some) broken teeth.

If the whine is even, it doesn't leak oil, shifts into all the gears easy (while driving), doesn't jump out of gear (accelerating or decelerating or downshifting) and doesn't buzz or vibrate through the shifter handle, LEAVE IT ALONE! But, if it does any of the above and none of the internal parts seem to be broken, then it is probably worth rebuilding.


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Tom Parsons

[This message has been edited by DZAUTO (edited 11-16-99).]

 

[joe58]

To varify if its a M20 M21 or M22. Just open the case and count the teeth on the input shaft gear.
M20 has 24 teeth or less on some models
M21 has 26 teeth
M22 has 26 teeth also but will have less of a tooth angle (about 20 deg. almost a straight cut)

 

[wolfdaddyss454]

MAN YOU GUY'S ARE GREAT!!!! Ive asked thousands of so called " great muscle car men" and this is the first practical advice Ive got

THANKS A BUNCH


[This message has been edited by wolfdaddyss454 (edited 11-16-99).]

 

[Doug Garland]

WolfDaddy, Did you get the email I sent you about the one I have for sale? Email me if interested!

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1972 Malibu (1 st. car) Project waiting to happen / Team Chevelle # 427 / A.C.E.S. # 1282


[This message has been edited by Doug Garland (edited 11-16-99).]

 

[ccrider]

wolfdaddyss454 -
I told you DZAUTO was an expert! When it comes to Muncies "he's da man".

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Thanks,
ccrider
Member #:267
ACES Member #:3379
66 Chevelle SS

 

[SSteve L]

Just a to add to Tom Parson's comments about whine- I lost some teeth on some of the gears in my M20 a few years back(I forget which ones, and don't have the foggiest idea in the world as to how stuff like that happens), but the trans needed new syncos and a couple of bearings, so I had it rebuilt. With the replacement gears meshing with the original gears, the trans whined a lot more than it ever did before the tooth loss incident. I guess I just say this to back up Tom's earlier statement that if it ain't broke, don't fix it, and if you do fix it and it is noisy, that's just a fact of life and you will have to live with it.

 

[SSteve L]

Calling Dr. Tom Parsons--

In your earlier post, you mention that leaking of oil on the front of a muncie is caused by the hole that the cluster shaft (also called counter shaft?) sits in is worn too big and can be replaced with a bushing. If this is so, is there a special tool or jig for drilling it out, and where do you get the bushing? I have never heard of this fix, as a matter of fact I know where there are at least 3 M22 'parts' trannys that are afflicted with a sloppy counter shaft fit, and we have been told by some (what seemed to be) really good transmission men that this was an un-curable problem. Please advise.

 

[DZAUTO]

One thing I forgot. It is VERY COMMON for a Muncie to whine in 1 or 3 gears if you replace ANY of the gears with new or used. This is because the previous gears have established a "wear pattern", and the replacement gear will not have the same wear pattern, thus a whine. It's OK. Live with it.

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Tom Parsons

 

[Gene Chas]

Steve, hopefully Dr. Tom will respond to the post with some experience, but I'll say that as a machinists apprentice way back when, we did allot of repair work on irreplacable castings. Lamborghini heads, my L88 heads, and the idea of reboring that hole is no biggie at all, assuming that during the weld process there is no collateral movement or shift in the case. Weld it up, strap it to a horizontal boring machine, and recut the hole. Hone to finish size. Can it be that easy Tom?

 

[DZAUTO]

STEVE, STEVE, STEVE, WHERE CAN I GET THESE TRANNYS!?!?!?! I WANT THEM RIGHT NOW!!!!!

I can have the most beautiful fix performed on oversized cluster (counter) shaft holes you ever saw. I have a man who can bore/bush the hole(s) and, if requested, move the hole centerline up closer to the main shaft to increase the strength (and whine).

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Tom Parsons

[This message has been edited by DZAUTO (edited 11-18-99).]

 

[SSteve L]

I am currently trying to contact the owners of the transmissions I have mentioned. I don't want to sound too excited to these guys so I can snap up the transmissions for a song and dance! Actually, the one that appeared to be in the best and most complete condition belongs to a long time friend who is a great guy that has never ripped off a soul in his life, and always lends a helping hand on your projects, so I will probably share this information with him. The other two are going to be mine, all mine, hee, hee, hee! I just have to track down the guys who will be none the wiser. One guy has ripped off plenty of people by selling them bad parts, or overcharging them for marginal ones, and usually takes advantage of novice gearheads. He sold my brother a bad set of heads then claimed we were trying to rip him off by giving him back a different set of heads and wanting the money back! (I owe him one!!). The other M22 I know of that I believe to need this fix is in possesion of a guy who has stolen more parts than he has bought, and although this tranny is probably stolen, I can probably horse trade my way to getting it for practically nothing! (He has some bad karma working against him!) In the meantime, I have talked to a machinist I know, and he doesn't think this operation would be that big of deal! Huh, I guess you just gotta know who to ask. The machinist is going to let me know what he thinks once he actually sees one of the transmissions, but I am very optimistic that he can do it. Is the forementioned bushing something you can buy, or do you make it yourself??

If I happen to scrounge up any extra M-22's or parts I will let you guys know!

 

[DZAUTO]

I do not do this repair myself. I have it done by someone who KNOWS HOW AND HAS BEEN DOING IT FOR YEARS. This is a very precise procedure and should only be done by someone that has lots of experience at it. Trust me. It costs $40 a hole (front and back) and is worth it to save a case (especially matching numbers). I would really discourage you from having someone do it who has no experience at it, no matter how good he is.

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Tom Parsons

 

[65Z16]

I fully agree with Tom. This is something for an expert that has done it correctly before, not a first timer or run-of-the-mill machinist. I have done my own M22 and other case repairs for a lot of years, but I have my own machine shop and the experience to do it right.

 

[SSteve L]

Advice taken! If I can actually get my hands on one of these transmissions, I will follow the above advice.