M22

[Wayne M.]

Re: M22

..... As far as Corvettes go, the M-22 was not singularly available with L-88. It was also available with 1966 L-72......

Joe -- I was always surprised that for a 4-sp. transmission option (the 1966 Corvette Dealer Order form (Rev 8/65) shows the M22 as being available with L72 engine only, with a qualifier of "not recommended for general use"), that the total installed in '66 Corvettes was only 15. After all, it was only $53 more than the price of an M20 or 21.

Makes me guess that some sort of Central Office permission was required.

BTW, whatever happened to your BB Chevelle w/M22 ? Did you trade it in on your new '69 Corvette ?

[Wayne M.]

Re: M22

My '69 Z28 had an M22 with fine splines on the input shaft, the M21 has coarse splines. Not sure if this is applicable to all applications.
Pierre

Pierre -- are you sure about the fine splines ? Per A. Colvin's book "C by-the N", the 26-spline input shaft debuted on 1970 454 Chevelles only, before becoming standard on all Muncie 4-speed aluminum [passenger and Corvette] input (clutch) gears across-the-board (M20/21/22) in 1971 model year.

I have an April '69 Z28 (Norwood) M22 and it has the coarse 10-spline input.

[Joe L.]

Re: M22

Joe -- I was always surprised that for a 4-sp. transmission option (the 1966 Corvette Dealer Order form (Rev 8/65) shows the M22 as being available with L72 engine only, with a qualifier of "not recommended for general use"), that the total installed in '66 Corvettes was only 15. After all, it was only $53 more than the price of an M20 or 21.

Makes me guess that some sort of Central Office permission was required.

BTW, whatever happened to your BB Chevelle w/M22 ? Did you trade it in on your new '69 Corvette ?

Wayne-----

I sold it to a private party and delivered it the same day I took delivery of my new 1969 Corvette---September 30, 1969. I recall watching it drive off, and I didn't have a tear in my eye after all the grief that car had given me in the only 17 months I owned it. I sure wish I had it back now, though.

[Joe L.]

Re: M22

Pierre -- are you sure about the fine splines ? Per A. Colvin's book "C by-the N", the 26-spline input shaft debuted on 1970 454 Chevelles only, before becoming standard on all Muncie 4-speed aluminum [passenger and Corvette] input (clutch) gears across-the-board (M20/21/22) in 1971 model year.

I have an April '69 Z28 (Norwood) M22 and it has the coarse 10-spline input.

Wayne and Pierre-----


I agree. I would be EXTREMELY surprised to find that any 1969 M-22 would have had a 26 spline input. It's definitely not what GM says was used, too.

[Pierre J.]

Re: M22

Wayne and Pierre-----


I agree. I would be EXTREMELY surprised to find that any 1969 M-22 would have had a 26 spline input. It's definitely not what GM says was used, too.

Joe and Wayne,
You guys are probably right, on second thought, I was probably thinking of my '70 Camaro. Sorry, I am getting older and loosing brain cells every day.

Pierre

[Tom B.]

Re: M22

I have had 2 M22s over the years. One was in my 1970 LS6 El Camino SS 454 I sold in 1974 and the other is this one I picked up at a swap meet 25 years ago. I bought it from a drag racer and it's set up as a crash box. It has a coarse spline input shaft and definitely has M22 gears, case numbers ect. I don't understand the code stamping though. This is the only stamped markings on the whole thing.

Any ideas? T3 13820

Tom

[Joe L.]

Re: M22

I have had 2 M22s over the years. One was in my 1970 LS6 El Camino SS 454 I sold in 1974 and the other is this one I picked up at a swap meet 25 years ago. I bought it from a drag racer and it's set up as a crash box. It has a coarse spline input shaft and definitely has M22 gears, case numbers ect. I don't understand the code stamping though. This is the only stamped markings on the whole thing.

Any ideas? T3 13820

Tom

Tom-----


I think this is likely a SERVICE case. If so, these numbers apply to the case only and not a complete transmission. Just what they mean, I do not know.

[Tom B.]

Re: M22

Thanks Joe. I had a feeling it was an over the counter case. Given it's history it's possible that the trans is a compilation of parts from other broken drag race transmissions. It is in excellent condition though.

Tom

[Wayne M.]

Re: M22

Tom -- I agree that it's an over-the-counter unit, but allow me to give my personal interpretation of the stamping as follows:

In spite of the lack of assembly code (ie. P3B23C) or a VIN, I think that the stamping might actually be CT3 and 43820. Aluminum "whacks" are notorious for faint or missing off-angle characters.

Now the CT(model year) series of OTC are fully asssembled transmissions, and usually have the assembly date code as shown in pics. However, OTC CASES ONLY, with Lisle magnetic plugs, in comparison, have a CC(year) code [ie. CC3_35956 actual example], and of course, no assembly code or VIN. Is it possible that the 2nd letter, T= complete trans; C = case assy. only ?

Is your cast # 3925661 (or 660) ? I attach a pic of a CT3_41775, a M22 assembled in June of 1972 (I think).

I have another OTC in my own car P1D19C (April 19th, 1971) CT1_43265. I know the lineage of this as a previous owner of my '65 lived in Marshall TX (he worked as a parts counter man at Nehls Chevrolet -- so he probably got an employee discount ) when he installed this OTC trans in my (his) car. It's obviously not the original, but it's music to my ears (neighbors will not agree) in first gear. Poor pic, but I don't have a lift, and it's still in the car after 21 years that I've owned it.

I have a feeling that the OTC numbering sequence for fully assembled transmissions might have started at 40,000 for each model year (CT0, CT9, CT3 etc.). In fact, there's an eBay CT9 that had exactly 40000 for a P0910A coded assembly (Sept 10th 1968 ?).

Could you re-examine your trans stamping with various lighting angles to see whether my hypothesis might hold water ?

[Tom B.]

Re: M22

Wayne,

I noticed yesterday that the stampings were at a severe angle. Looking at it this morning with a bright light I can see that it is indeed CT3 and 43820. The C and the 4 are very faint but there. The case is a 661.

Thanks for the insight. I wonder why mine doesn't have an assembly date code.

Tom