Rear-end switch

[dmulhall]

Hey guys,

anyone know of a lower geared rear-end that

fits decently into a b2b?

your help would be greatly appreciated,

I'd like to get a few more out of the top end on the highway..

thanks guys your always helpful

Dave

[Ken_Hart]

Do you mean higher gears to lower the RPM and get more top end speed?

[Reg Evans]

I installed a 66 T-Bird 3.0 rear end under my 52 1/2 ton. Just had to move the spring perches and have my drive shaft modified. This works great behind my 251 Chrysler L6.

[Guest flathead6]

I had my 4:11 gear set (the pumpkin) in my b-1-b changed to a 3:54.

Hollander interchange had a match from a 50's chrysler 6 cyl car pumpkin.

It was a direct fit, I took it a bit further and had the gears swapped to my pumpkin since the cars case looked a little different.

You wouldn't know they have been changed if I hadn't told you.

At 60 mph I'm turning 2700 rpm... I can't recall the exact tire size I'm using but it is as close to the OEM 16 inch size I could find in a radial.

Hope that helps.

Steve Hanks

[Jim Shepard]

Hey flathead6! Do you remember what year and model Chrysler you used?

[Byronb3b]

The rearend ratio in my '48 Chrysler Windsor is 3.54, used in the cars with fluid drive and the underdrive M-5 transmission. IF I remember correctly. I can do some searching in some of my manuals and dig up some more info. on years used.

[Guest flathead6]

Jim I wish I did...

You might find a late 40's early 50's Hollander interchange manual at your local library or an old junk yard to check. All I can recall is that it needed to come from a early to mid 50's Chrysler car with a 6 cly in it.

The bolt pattern for the pumpkin is the same the case is a little different since it has a rubber bumper on top.... The reason for the bumper??? axel wrap? or the springs bottoming out? I'm guessing.

The car pumpkin fits as is, but you can swap the guts to make it look stock.

Hope that helps.

Steve 208-791-7313

[Young Ed]

I think any mopar from the 40s up to 52 is a direct swap. I have a 50 ply 3.90 diff in my 46 pickup and a 53-54 3.73 diff in my 48 ply. The 53-54 one required taking it apart as the spline count on the axle changed in 53. So I have the old side gears with the ring and pinion from the 53-54.

[Jim Shepard]

Thanks, I'd appreciate that...

[Byronb3b]

My chrysler parts manual lists the 3.54 as the standard ratio for the '46-'48 chrylser six cylinder models with the fluid drive 3.9,4.1, 4.3,4.56,4.78,and 4.89 also listed as available options. I am sure these plus otheres were offered on all mopars. I think the ratio is stamped on the top web of the differrential. Hope this helps. Byron

[Phil Martin]

I got a 3.21 out of a 73 dodge pickup. The width is real close. Ihave the old mounts off, I will use the ones off my rearend. Hoping it works out real good for highway use.

[55 Fargo]

Do any of you fellows know if the pumpkin can be changed in the 47 and 48 Chrysler 6 cyl cars. I have a 48 Chrysler Royal Coupe, the engine and 3 spd standard trans, and dry clutch are from a 1951 Canadian built Dodge it's a 218 long block, the diff is of unknown origin, it has the covered leaf springs characteristic of the 48 Chrysler. I could not find the stamp on the hog head to determine the gear ratio. But when I roll the car and mark the tire and the drive shaft, I get just over 4 to 1 revolutions, it's either a 4.11 or a worse 4.30. I have a 47 windsor parts car with a 3.54 diff, would like to pull the pumpkin and change it into my diff thats on the 48 now. This would sure help on the highway, it's real flat land around here, and I don't plan to pull a trailer. Any advice or help would be appreciated...........Thanx Fred

[Byronb3b]

Fred, Should fit right in, my book shows all mopar six cylinder 1938-1948 with the same part number for the housing. byron

[55 Fargo]

Thanx Byron, providig the diff is from those years, would if had come from the 1951 Dodge, don't think so thouigh, because it has 11 inch brakes...........Fred