VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 1940 transmission interchangeability question

With the exception of new used transmission being very low on oil, it appears to be in good shape with minimal fork wear.
Can anyone confirm the year of this trans? Stampings are as follows
591193
GM 1
41
130

Also thinking front and rear bearings should be replaced to prevent oil leaks. Thoughts on that.

Still working on pulling old trans.

41 trans has 2 bottom studs facing downwards which bolt to the frame mount. The 40 has two bolts which screw up from the bottom into threads in the trans. Hopefully not an issue, just a different mounting/ fastening approach....

It is a 1941-1948 transmission made in 1941.
The ransmission bearings do not hace seals and will not cause leaks. How ever they do make a sealed bearing for the front bot is not necessaey.. The gear oil must pass though the rear bearing to get the oil to the U joint.

1937-1946 had a stud that threaded into the case and was not a bolt.

My neighbor stopped by this afternoon and helped me pull my old transmission which I had been struggling with pulling by myself. He placed a jack underneath the flywheel area and raised it slightly to take the weight off the transmission afterwhich the trans came out easily. He then inspected both transmissions and ended up pulling the guts out of the 41 and putting them in my 40 housing as the components on the main shaft in the 41 were like new. Now I can begin the cleanup and assembly process. My neighbor coincidentally owns a 47 Chevy Suburban Woody which he is in the process of rebuilding.

I thing exchanging the parts was a good move. Now you have some idea as to what you have.

I just thought of this....the 1941 front bearing retainer (bolts to front of case) was made from pot metal in 1941. Most broke in the first few years and have been replaced with cast iron. Make sure yours is cast iron.
Also fill the grove in the inside of the throw-out bearing with a high melting point grease and coat the outside grove or area the fork rides on.
Good luck with your project...

Great observation about the differences betweenfront bearing retainer. I just checked and the 41 looks to be aluminum...it's very light. My 40 is cast iron and was put back on...

PS I also pulled off the vinyl bug screen that I placed in front of the radiator, based on your advice on another forum covering the 1955 vintage since I installed a 55 235 engine last spring.

The 1940 can be a hot running engine out on the highway in hot weather. They need all the help they can get. If you do have a hot running problem install a 1941 radiator. It is a direct fit and provides better cooling.

I am anxious to hear how your new transmission is performing.

I ordered the rubber boot for the vacuum assist and the adjusting grommet plus ball seal from chevy of the 40s so it my be a week or so before I have it running.

Finally completed the transmission install on Saturday.
I opted NOT to reinstall the vacuum assist because I was curious to see how the shift kit, that came with the new trans, would work compared to V.A..
I am pleasantly surprised how well this new shiftkit setup works!
I never liked the fact that I couldn't shift gears if the engine wasn"the running

The vacuum shfit can be shifted without the engine running. It ust take a slow steady pressure on the lever to move the vacuum piston.