Dealer replacement M22 codes

[bitfactr]

I purchased a '70 LS6 Chevelle from the original owner
a number of years ago. The M22 in the car at the time was
said to be a dealer replacement done in '72 after the
original was damaged (luckily the original trans was kept
and since repaired). But I'm trying to decipher the codes
on the other/dealer trans.

The straight-forward numbers are the casting number
(3925661) with stamp (WJ), with date code P2K06C: Muncie,
1972, July, the 6th, M22 ratio.

It doesn't have a sequence number, but to the left of
the date code is OT3 with 40201 below that. There is also
an "A" stamped on the top and a 5 cast into the side of
the case near the date code? I can provide photos if it
would help. Anyone have any info on these codes?

Thanks,
Dennis

[Mr70]

Welcome.
I think you've pretty much deciphered it.
Are you sure that's not the letter C before T3?..that would be more reflective of what I have seen.
That 3 may be standing for 1973,as the designated warranty year.
It sounds like it is holding a sequence number.
Muncie did assemble replacement transmissions for Chevrolet starting with sequence #25000,up to #44999 during that particular model year.
That 3925661 maincase was shared by M-20-M-21 & M-22 as well.
1972 was the last year the M-22 was installed in production vehicles also.

[SS427]

Welcome aboard Dennis! I know you have been poking around and good to have you aboard. Good group of guys here with rare exception.

[bitfactr]

Mr70,
Thanks for the info. OK, so the 40201 is a sequence
number, just for replacement trans. It does appear it
is a CT3; the casting is a little rough in the area of
the C, which caused me to mis-read it. That apparently
just means it is in warranty until '73?
Thanks again,
Dennis

[Mr70]

The 3 would stand for the last digit of the model year the transmission was actually placed into field service.
The warranty on it woulda started in 1973.

[bitfactr]

Mr70,
Thanks for the clarification.

And thanks to both of you for the welcome.

Dennis