mikejpss

was the m22 manual used in the 81 models? or some other standard tranny? seller says the car has a m22, just trying to verify that fact.
thank you

birdsmith

I don't believe the M22 was available much beyond 1970, if then. A Muncie M22 is known as a 'rock crusher' and was somewhat biased toward competition use because its gear teeth were cut straighter than the M20 and M21 which produced a signature gear whine. It was also a 'close ratio' box with a rather tall (numerically low) first gear. Any four-speed that would have been available in 1981 would have been a Borg-Warner T10 which was similar in many ways to the Muncie design and can still be purchased new from Summit racing for around $1800.

qtlow

Not from the factory they didn't that's for darn sure.
That's not saying someone couldn't bolt one right in but I'd say the chances of it being a real M-22 are slim.
Seems like everyone thinks they've got the famous M-22 but most people can't tell the difference between it or any other Muncie.
I'm not sure but I think the 81 came with the Borg Warner T-10.

MelWff

check to see if there are 2 plugs on the side of the case, one for fill and one for drain, that would increase the change of it being an M22.

L88Plus

81's with manual trannies came with aluminum case Super T-10's, no Muncies, Saginaws, Doug Nashes, Tremecs, Lencos, Jerichos, Viper T-56s or T-10s. Or any other manual tranny for that matter. Just the BW ST-10.

gbvette62

The last year to use a Muncie was 74, from 75 through 81, all Corvettes had BW Super T-10s.

ZZ71S

http://www.5speeds.com/muncie2.htm

Budman68

You would know if you had a M22. Snap, bang, rattle, whin.... the are very noisy. You basically jam it into gear at idle and sometime get a nice chatter going into second to slow. lol.

mikejpss

Thanks everyone. It seems the seller "thinks" its a m22, or so his uncle told him so. Now that I'm educated on the differences, he's probably has the SuperT10 . I will ask for pictures to verify.
Again, thanks for the info on such a short notice.

gkull

BS alarm! They were only sold in the highest hp GM stuff around 1970.

They were very noisy with gear whine.

Rebelrob

I am pretty sure, but I had a 79 Z28, and I had the original window sticker. I was 2nd owner. And it said M-21 4 speed for the trans listing. But the actual transmission is an aluminum Borg Warner as mentioned above. I still have the trans but not the car. It was the close ratio model.

milo30

Just ask if he ever changed it if not then look up the code will probably be M21. It didn't come with M22 but doesn't mean that it was never replaced and they put on in.

gbvette62

M21 was the GM order code for a close ratio 4 speed, it did not designate any particular brand of transmission.

From 63-65, all GM 4 speeds carried the RPO M20. Certain horse powers got the close-ratio, and others got the wide-ratio. It made no difference if it was an early 63 with a BW T-10, or a late 63-65 Muncie, they all were M20's.

GM first offered the M22 in 66, and changed the RPOs. From 66 on, M20 was the wide-ratio, M21 indicated the close-ratio and M22 was the RPO for the "Heavy-Duty" 4 speed. These RPOs continued to be used from 66 to 79. 80-81 4 speeds were RPO M18.

The hobby has adopted M20, M21 & M22 to designate Muncies, but to GM, these RPOs only designated the type of trans.

An M20 can be a T-10, a Muncie, a Super T-10 or a 78-79 Saginaw. M21's can be a Muncie or a Super T-10, while the only M22 made came from Muncie.

joewill

yes I agree, its pretty easy to tell with a pic, so post one of you can..
if it is a muncie then it can be anything since it cannot be original.
if it is a super t-10, then it 'might' be original. but not a M22

if the seller is stating it is an original to the car muncie, then assume he is incorrect in the description of the other details of the car.