My '68 442 4-speed convertible has a metal tag on the transmission, driver's side, secured by a bolt on the side of the transmission, but near the bottom, which reads "3915079". Can anyone tell me what this signifies or means? Any information will be welcome

 

I know hardly any thing bout muncie transmissions.

A google search does come up with similar numbers, but those are casting numbers. It also talks about bolt on tags with your exact number.

Google "muncie 3915079" comes up as "M20 with L78."

Just trying to help.

 

Mine has 3915085 and when I did research, it indicated it was an M21. I would assume another number (yours) would mean M20 as it is a 4 speed (as the only other 4 speed was an M22 which shouldn't have been on the 68), as the other post indicates. They made it easier in late 68, and at least by 69 by using an A, B, or C in the last digit of the date code of the transmission (A=M20, B=M21, C=M22), instead of having the tag (not sure if they did it to make it easier, but at least you will always know what the trans is in a stamped casting vs, a removable tag...

 

3915079 is the part number for the 1968 wide ratio 4 speed (M20).

 

Where would the location of that A,B, or C code be stamped on the transmission? My car was delivered in June 1968, so I assume it would be a late-manufactured car.

 

It would be in the trans date code. Mine is P8A17 (January 17, 1968), and has no Muncie designation because the letter is not at the end of the date code. If my memory serves me correct, I believe this code is stamped on the driver side back end of the trans. I will post a picture of mine to show the example if I can find it.

 

Here is the pic...

 

The A-B-C ratio indicator didn't start until late Oct of 1968 calendar year, for Muncies used in the 1969 model year and later...
The ratio indicator won't be stamped on any 1968 model year Muncies...

Hope this helps... Crash