The Stovebolt Site Forums The Parking Lot Big Bolts Apache 12" 4.5:1 diff for big bolt?

I have a '48 1.5ton with 20" wheels and a 5.4:1 rear axle.
Instead of all the work of a 5-speed, I figure I can get the same end result (60 mph cruise) by installing a taller ratio diff. I have been looking at options and the rear axle in a 55-58 Chev 1.5 ton LWB pickup appears to have the same diff head unit. But on 15" or 16" rims- with a 4.5 ratio.
Can anyone confirm this?
Swapping diff heads is a morning's work. easy. Finding the right one not so easy.

I have not heard about this swap, but then again we didn't have a 1.5 ton pickup over here that I know of.

Let us know what you figure out!

Grigg

Casting number on the 1.5 ton diff head is 36522??, maybe 3652280.
The casting is 350mm/13 3/4" diameter at the mounting face. 1115 mm/43 7/8 inches circumference, and is retained by 10 bolts.
The rear cover is 340mm/13 1/3 " diameter, also retained by 10 bolts.

If the spring width is the same, you would be quicker swaping out the entire rear end.

The spring width is probably different. I have a big bolt, dual 20" wheels, the later smaller apache has single 15 or 16 inch wheels, but i read somewhere, fully floating wheel bearings.