The Stovebolt Site Forums The Shop Area Driveline 3 speed column to 4 speed floor

I am planning on changing my 3 speed column to a 4 speed floor transmission both are 1949 mine is a 216 3100 with the 3 speed the other one is a 4 speed 216 3600 will the drive shaft have to be altered?

That is an impressive 4-sentence, sentence. Periods are cheap and make the reading easier and clearer.

If both transmissions are 1949 for an enclosed driveshaft (at the rear of the transmissions), no modifications will be needed. You will need a u-joint for a 4-speed enclosed driveshaft transmission to a 1/2-ton enclosed driveshaft.

I think that if both transmissions are set up for an enclosed driveshaft, you can use the three speed universal joint with the yoke of the 4 speed.

The speedometer drive gear in the four speed will give you an incorrect speed/miles because the rear end ratios are different I believe. A speedometer shop can fix you up with a little external compensating gearbox.

I put a '49 four speed out of a 3600 into my '51 half ton many years ago.

Kurt

All the 1/2 tons were 4.11. You will either have to find a floorboard with a hump for a 4 speed or cut an awfully big hole. Any particular reason for a 4 speed? 1st gear is almost worthless and reverse is terribly slow.

The 4-speed floor cover fits in the same space as the 3-speed floor cover.

Kurt is correct about the u-joint and about the speedometer drive/driven gears - the four speed is out of a 3600, which would have a 4.57:1 ratio (the 1/2 ton has the 4.11:1 ratio).

In this thread he mentions wanting to go to a floor shifted transmission. As there seems to be no floor shifters for the torque tube 3 speed listed (I bet the later open style can be modified to fit), he's probably looking for other options.
I am in agreement, not much to be gained going with the SM420, the overall gear spread is terrible for a driver. A 3.11 Saginaw with the Patrick's conversion would be better, 4th will still be 1:1, though.

The SM420 is a much much more robust transmission than the 3 speed. That's why I switched. Plus, if you want a floor shifter, there is no easier way to get one . Plus you get the creeper gear. Plus it's still a stock configuration. 2nd through 4th is functionally the same as 1st through 3rd of the 3 speed. Final drive is 1:1 same as the 3 speed.

I think the SM420 plus Patrick's lower ratio differential gears would be about perfect for a daily driver. Forget all this swap the rear end, overdrive tranny stuff LOL.


Kurt

Thanks that is what I am lookng to do

Forget the previous post this comany is for cars only will not fit trucks.

Bennie