Is an Overdrive avail for 1947 Sedan?

[edhd58]

I put 3.54 gears in my 42, it now cruises 65 to 70 with not much effort and still lugs good in second gear a low low speeds. It has the G 226 six cylinder.

[blucar]

Re-gearing the rear end from 4.11 to 3.78 is not much of a solution for good everyday driving, an overdrive give a vehicle the ultimate option of having multiple ratio's when needed.
The Columbia two speed actually has six speeds forward, where-as overdrive transmissions do not. My '36 had a Columbia in it when I bought the car in '52, I converted it to a '42-48 unit with the later model controls in '55. I have never had an issue with my Columbia in 95k miles of operation. The gear ratio in my rear-end is 3.78.
I have driven the car in daily traffic on the So Cal freeways and the open highway between Ventura and Idaho, 980 miles of non-stop driving at 70 plus mph. I have also street raced the car when I was younger, again never an issue with the Columbia, however, I did waste several transmissions.

[Vintage Copper 47]

Originally Posted by edhd58

I put 3.54 gears in my 42, it now cruises 65 to 70 with not much effort and still lugs good in second gear a low low speeds. It has the G 226 six cylinder.

Using this chart from the "green"book, according to the turtle number on my speedo drive of 19, with my stock 6.00x16 tires, it says I have a 3.78 rear end.. after replacing the motor mounts, I have got the car up to 65 cruising with no problems.. so if I really want an overdrive, it can wait!

[Jefscoupe]

I realize this is a few months old but I have a couple Ford OD trans.
The car they came with was a 48, is that when the OD transmission came out?
Will a V8 trans fit a 6? 48 fit a 47?

[40cpe]

Ford didn't offer an overdrive in the '48 cars. If yours has one the car has been modified. A picture of the transmission would help identify it's type/vintage.

[Vintage Copper 47]

Sponsored Links (Register now to hide all advertisements)

Originally Posted by Jefscoupe

I realize this is a few months old but I have a couple Ford OD trans.
The car they came with was a 48, is that when the OD transmission came out?
Will a V8 trans fit a 6? 48 fit a 47?

I am not sure.. I do know the bell housing to the motors are different for six cylinder engines.. but i think the rears are the same, as they use the same transmission..

[Jefscoupe]

The transmissions I have came with the 48 I had. They weren't IN it.
I don't know what they came out of.
I can say one is an open driveshaft side-shift model. The other is buried under a bunch of flathead parts right now.

[1931 flamingo]

Millington,TN.................NAS Memphis.............65-66

Paul in CT

[rotorwrench]

Lincoln had the Borg Warner electric overdrive a good bit before the 49 models came out but you can really tell those old Lincoln boxes due to their long length and large aft mount set up since they were still a torque tube drive. You don't see too many of them out there for sale now days and they never made one for a 6-cylinder. A person would still have to do some mods to make one of those long rascals work with a V8.

Changing the rear axle ratio is the least expensive way to go. Those old 226 6-cylinders will pull near as good as a V8. They certainly have plenty of torque.

[blucar]

The big problem with re-gearing a differential, and/or installing oversize tires to increase ratio and lower RPMs is that the vehicle only has one ratio that might be fine for open road driving, however, in the city and/or mountains the vehicle will lack power requiring running the vehicle in second gear.
An over drive provides the best of two worlds, high gear ratio for open road use and low gearing when power is needed in the city or mountains.
I know several people that have fallen into this trap of not knowing that an OD vehicle has to have low differential gears in order to work properly...
A modern SUV/pickup will have 3.42 gearing with a conventional trans, an OD trans will have 3.73... The Ford F100's of the mid/late '50's had on the average 3.72 ratio with a standard trans, an OD trans had 3.89 which was the same ratio as a F100 4 x 4 .

[Vintage Copper 47]

Originally Posted by blucar

The big problem with re-gearing a differential, and/or installing oversize tires to increase ratio and lower RPMs is that the vehicle only has one ratio that might be fine for open road driving, however, in the city and/or mountains the vehicle will lack power requiring running the vehicle in second gear.
An over drive provides the best of two worlds, high gear ratio for open road use and low gearing when power is needed in the city or mountains.
I know several people that have fallen into this trap of not knowing that an OD vehicle has to have low differential gears in order to work properly...
A modern SUV/pickup will have 3.42 gearing with a conventional trans, an OD trans will have 3.73... The Ford F100's of the mid/late '50's had on the average 3.72 ratio with a standard trans, an OD trans had 3.89 which was the same ratio as a F100 4 x 4 .

So that being said Blucar, Having 3:78 gears may be perfect when I add an overdrive (columbia or mitchell)..?

[jake197000]

i have 3:78 gears and a columbia in my 46 coupe and just love it. drivin it to a couple central meets great on the highway.

[Automotive Stud]

Originally Posted by Vintage Copper 47

So that being said Blucar, Having 3:78 gears may be perfect when I add an overdrive (columbia or mitchell)..?

I have a mitchell in my '47 coupe. I did have to notch the floor under the back seat a tad. I'd still prefer it to sourcing parts for a columbia. I have the 30% and I love it, it's been in there about ten years now.