WAs told its the HD muncie 3 speed from a 69 SS396! Its been weeks of off and on research and the numbers pull me in too many directions!

First off, It has a nice hurst shifter with it,
and its definitely a 3 speed,
cast iron case
7 bolt side cover
Casting GM7 3952646
LI18

27 spline output shaft
10 spline input shaft with a ring grove about an inch back

The stamped VIN is 30M315964

Main case casting is GM4 l228
3852882 (2662?)

Tail casting right by the spedo drive
3911942
GM1
H99 (H88?)

Aluminum tag under a side cover bolt has (3?) 952657RM

There are some remnants of red paint on it in some places.


Please!! can anyone help me out? I jsut....dont understand waht the sites are saying when they say something like....one inch letters on right side means 3.08 1st gear, etc.....

HELP!

THANKS!!

I just noticed there was one more stamping on the main case jsut below the sidecover. It is

Hoa12b

69 3 speed HD trans was the Muncie (RPO MC1) and had a main case casting number of 3911940.
Saginaw 3 speed (RPO M15) had maincase casting number of 3925647 for the 6 cylinder and 3925647 for the 8 cylinder.

3952657 shows in the Chevy parts catalog as HD 3 speed transmission for:
69 Chevy,Chevelle,Camaro (350)
69 Pass. (P/Track. w/3.73 axle)
72 Chevelle w/Muncie

Did Muncie ever make a cast iron case transmission? I know all their four speeds were aluminum.

My guess is it's probably a Saginaw three speed. The Muncies don't have any numbers on the side cover side of the transmission, and the Borg Warners I've seen have their assembly stamps on the area directly behind the side cover. The Saginaw I had had it's assembly stamps directly below the side cover. If I've still got it in my photo bucket account I will post a picture of the stampings on my Saginaw.

http://i160.photobucket.com/albums/t164/MEJ1990TM/Saginaw%204%20Speed/16.jpg

Is that what the numbers on your transmission look like?

No, doesnt look like that at all.
looks just like this....

http://www.camaros.org/images/pages/decoding/trans_MC1_code.jpg

Im thinking that the stamped code on the right side of the case (30m315964) is the key to the ID, but i cant find the decoder that tells you what make (chevy, olds, pontiac, etc...., what plant it came from, and what the date was.) I know its in that code, because I have see others, and as little info as I can find on it was on an olds site and lead me to believe that the 'M' meant Olds in that code.

Anyone know where a breakdown of the vin codes are? Ill go snap pics real quick...

I just realized that there is a big tall RM in yellow paint on the case. Maybe this is meaningful?

Here is the pic of the side cover, and a closeup of the stamp, tag and RM
http://img.photobucket.com/albums/v216/ibuiltmine-o1oo/IMG_1317.jpg

http://img.photobucket.com/albums/v216/ibuiltmine-o1oo/IMG_1318.jpg

Thats a partial VIN and doesn't give the date.
3 = Oldsmobile
0 = 1970
M = Lansing assy plant
315964 = sequential build #

But the Hoa12b code does:
H = 69 Muncie HD 3-speed
0 = 1970
A = January
12 =12th day of month
B = 2.42 first gear ratio

Ugh.... now you know why Im pulling my hair out. Now BOTH those stamps are on the main case. no way it was at once two separate trannys. not possible, and neither stampings look to ever been messed with......
Please tell me where you find that decoder?

FAmily dinner in Ft. Collins tonight... be back on here in a few hours!

OK ,both stamps are on the case.
So it's a 1970 Muncie HD 3 speed from an Olds made in Lansing,MI.
Where's the confusion?

cool! thanks! Now...where do I find that info?