The Stovebolt Site Forums The Shop Area Driveline 1953 Chevy Panel Truck Transmission Questions

Good afternoon fellow Bolters. I have a 1953 Chevy 1/2 ton 3100 Panel Truck. I have a 235 engine from a 1954 Chevy Panel truck (blue flame) , I have the original rear end and torque tube, and I have the original 3 speed transmission with shifter on the column (3 on the tree).

I just bought a 1950 Chevy Panel Truck for parts only and I'd like to put the 4 speed transmission that came with it in my truck. I have my original rear end and torque tube and I have the rear end and torque tube and 4 speed transmission that came with the 1950 Chevy 1/2 ton panel truck. QUESTION - will the 4 speed transmission (1950) bolt up to my 235 engine (1954) and use whichever torque tube will join it all up , this should all bolt together, correct?

Another BIG QUESTION is - With the 4 speed transmission, I know that 1st gear would be granny low, then would 2nd, 3rd and 4th gears be like the 3 on the Tree gears? I know I have to put in the metal panel on the floor for the 4spd.

Maybe this thread should be moved to the Driveline Forum?

Agreed and done.

Garageguy, to answer your questions. Yes, the transmissions and bellhousings will swap in without issue. The 4 speed and 3 speed torque tubes should be the same, the only difference would be the front yoke and bell on the rear of the 4 speed vs the 3 speed.

Gear ratios for the SM420
1st - 7.05:1
2nd - 3.58:1
3rd - 1.71:1
4th - 1.00:1
Rev - 7.05:1

Gear ratios for the 3-speed. (from 1951 Service Manual - apparently the later 53-54 heavy duty 3-speeds are slightly different)
1st - 2.94:1
2nd - 1.68:1
3rd - 1.00:1
Rev - 2.94:1

So it looks like your starting gear (2nd on the 4 speed,) would be a little lower than on the 3-speed, just meaning you should shift out of 2nd a little quicker than you would our of first with the 3-speed.
Reverse is also way lower on the 4-speed (so NO RACING in reverse )