The Stovebolt Site Forums The Shop Area Driveline Differential swaps

I seem to recall reading that I could swap a 1953 / 54 3.55 PG differential complete with the Torque Tube into my 1941 1/2 ton rear end housing. Any truth to that? Seems too easy. Thanks, JVV

No. Completely different housings.

Maybe they meant the whole assembly, would that be possible?

Perhaps. I'm not 100% sure if the transmission end of the torque tubes are the same or not between Passenger and Truck. I do know that the Passenger has a shorter wheelbase, which could be an issue. Someone with more experience with the closed drivelines should see this and give you more accurate advice, as my experience with them is really limited to Passenger cars. The only Truck drivelines I've really worked with have been open.

Thanks, wish I could find the article that I read to see if I recall it correctly.

A truck has a round mounting pattern where the torque tube mounts to the axle housing, a car is oval.
Installing the whole axle housing and torque tube as an assembly may be possible, but axle width and torque tube lengths would need to be confirmed.
1940-54 passenger and truck use the same spline at the front.
I think it would be less work to put the aftermarket 3.55 truck gears in your housing.

I have installed an AD (year unknown but 48-54) torque tube and rear axle assembly under a 1940 one-ton. The rear axle housing was already in place when I got to the truck so I do not know what was done to make the housing work.

Do you have a short or long bed?

There are a few different lengths of torque tube, so if the one you have is the correct length, you will need to likely use two u-joints to make one that will work.

The reason I mentioned the 54 was it's a 3:55 ratio, is your conversion also a 3:55 or is it a 4:11? I don't have the truck yet (will pick up in March) so I don't know if it's a short or long bed, but I think it's a short bed. I'm at work now so can't call and ask the owner.

Check 1929 - 1954 Master Parts and Accessories Catalog
Group number 5.504 -Carrier Assembly (torque tube lengths) 1934 to 1954

Torque tube lengths:
55 55/64"----1937-38
56 39/64"----1937-40 Passenger car
57 19/64"----1939
59 1/2"-------1941-53 Passenger car
58 1/2"-------1941-46
62 1/2"-------1947
60 1/8"-------1948-54
N/A------------1954 Passenger car (check next Post)
53 7/8"-------1954 w/Hydra-Matic trans.

1941 to 1953 they used same length torque tube with the power-glide and manual shift transmissions. 59 1/2" inches
Ring & pinion for PG 3.55 (I do not know the 1st year PG was used)

Ring & pinion for manual (passenger car)
1951,52 - 4.11
1953 Model 1508 4.11, all others 3.70
1954 3.70

1929 to 1957 Master parts catalog does not show length of torque tube for 1954 passenger car.
But shows length of the propeller shaft. Here
Which says, 1941 to 1954 Passenger car all used the same length propeller shaft...63" inches
That tells me the 1954 Passenger car torque tube is the same length as 1941 to 1953 torque tube. 59 1/2" inches
Your 1941 1/2 ton torque tube length is 58 1/2"inches
The 1941 to 1954 Passenger car torque tube is a inch longer than the 1941 1/2 ton torque tube.

How to measure torque tube

Something to take into consideration.
The truck axle is made of a heavier construction than the passenger car axle.
1942 Chevrolet Shop Manual
Read Under:
>Rear Axle Assembly, 1/2 ton and 3/4 ton trucks
>Pinion Assembly---1/2 Ton Model
>Axle Shafts

The Powerglide came out in '51. While the lengths might be the same, the '49-'54 has a different differential than the '48 and earlier Passenger.

I think the Powerglide was introduced in 1950?

6 bolt wheels (front hubs & rear axles) in cars up through 1948.
5 bolt wheels (front hubs & rear axles) in cars 1949 and later.

I think the axles can be swapped between years (for torque tubes).

Wow, Thanks for all of this information, when I get some time I'll review it more closely. I do appreciate your effort to put all of this together. I'll also try to find my original reference that started this conversation.

Thanks again, very helpful.

JVV