The Stovebolt Site Forums The Shop Area Driveline 46 Transmission ID and Info

Hi all,

I'm digging into the transmission of a 46 half ton. First of all, I'm interested in getting more info about the casting and serial numbers. Less info seems to be available online than for the engine. Casting number is 591195 which is from 41-46 but what does the GM2 identify? The serial number also has a DO at the beginning, does anyone know what those stand for?

Also, I'm looking for some rebuilding resources besides the shop manual. I'm more visual and am newer to this. YouTube is failing me on this specific transmission. There are plenty of videos on different transmissions, but does anyone know of any other resources for the 591195 top load 3 speed manual transmission?

Thanks!

"DO" is a Muncie 3-speed transmission.

I believe GM2 identified the master mold used to cast that transmission...

Mike B

Thanks Mike, that was the one thing piece that I was missing. Are all of the 3 speed Muncies the same inside? ie are the gears the same from column to floor shift? I've seen a number of rebuild videos and wasn't sure if there was variation. Thanks.

I can't answer that without a lot of research, which you can do yourself at Keith Hardy's web site.

http://chevy.oldcarmanualproject.com/

Chevrolet used Muncie, Toledo and Saaginaw transmissions in the 3100 trucks and I don't know them well enough to know if each type was available as column and/or floor shift.

Does anybody know what RPO-318 is in 1946?

Mike B

I do not know the transmission "name/number" but, it is listed on page 80 (TRANSMISSION) in the 1946 Chevrolet Specifications Manual.

The Truck Data Book shows it as the optional 4-speed transmission for 3100/3600.

Thanks Tim!

Mike B

Thanks all. I have a shop manual on the way, but have used the online versions for other things. Will have to continue to dig into it to grasp the specifics of what I have. I'm sure more questions will surface and appreciate your background.