The Stovebolt Site Forums The Shop Area Engine Shop 38 chev transmission

Hey fellers; If the running gear on the 38 commercial 1/2 ton is the same or equal with the sedan, will the truck transmission gears interchange with the sedan tranmission. Just the gears, I know the case mounts different. It would be possible to interchange the gears, or does the sedan have some synchros? If I had a truck tranny I would experiment. I'm in the market.
Oh! No I am not interested in any further mods to the running gear, every one has their preference.
thanks

are we talking 3 speed or 4 speed transmission. the three speed truck transmissions should have syncros. the 4 speed transmissions were "crash" boxes. I don't know about the car stuff. I have a 3 speed out of a 41, and the 4 speed from my 1940 3/4 ton. PM me if interested.

John

Gears will interchange between car 3-spd. and truck 3-spd. from at least '37-'38-'39 cars, except for the output shaft if I remember right. In '40, the 3-spd. gears all became helical cut instead of straight cut, and will not interchange with any of your '38 3-speed gears.

BIG BAD DAD
Yeah A Pickup 3 speed. I have a 38 sedan 3spd on hand.
I also have a 37 P.U. 4 spd. on hand
In the truck presenly is a 1950 4 spd (its got to go)but it is synchro gear, also too much for a too little truck.
I would like to replace with a 3 speed pickup.
My thought was if a 3 speed pu was in questionable shape, grab the gears from the sedan 3 speed.
I would replace bushings and bearings.

That's right, Barry, but I believe the gears in a 40 to 54 will fit in a 37, 38, 39 transmission case as a set. The input shaft from 37 to 54 has the same splines on it, but the output shaft from 37-39 is different than from 40-54. They have more splines, like the car. So, if a guy has a three speed transmission case out of a 37 or 38 (which are both the same) he can install 41-54 gears in the case and be running a more advanced and stronger transmission than the original transmission, if he uses the front part of the car universal joint. I'm not sure any of this will help, but I have been thru the "the exercise" and know it.
Joe

Barry
I vaguely remember something to that effect, both from previous posts and some research on my part. BUT it never hurts to float that past someone with the knowledge,
Thanks for jumping in.

Hey Uhaul 6 pack over Texas;
Now you have PQ'd my interest, as a matter of fact I have 2 three speed chev trans under the bench. When my father inlaw had his junkyard I sort of rebuilt a couple of chev trans, they are rather simple(like me) compared to all the bits in a "F" product. Thats why I said I would replace the B and B's.
Be cause they have the side shift forks unlike the top, I never gave it an outside chance the gears would be the same size, or that the case dimensions were the same. All I know is they are 49-51 with an extended tail shaft.