Posted by Keith in Washington [108.162.245.245] on Monday, January 30, 2023 at 14:58:53 :
In Reply to: I need to go BACKWARDS (DOZERMAN question!) posted by Ddd [172.68.35.50] on Monday, January 30, 2023 at 10:07:08 :
OK you got me thinking on this one. My 42 WC53 has the small 8 3/4" differential in the front axle. When I rebuilt the truck I went from 5.83 ratio to a 4.89. I have a V8 so no problem. The back axle was a piece of cake as the military swapped in a later large diff axle at some point.
To change the ratio on the front axle, I bought a basically new 1/2 ton 4.89 gear set from DC. I got only the ring and pinion and installed it into the small 3/4 ton 4 pinion diff carrier for the front axle. So there is a 8 3/4" 5.83 gear set. I guess I might have one laying around some place.
The 3/4 ton front axles had 3 different differentials through time. The earliest ones has a 8 3/4" 2 pinion carrier, that was replaced by a 8 3/4" 4 pinion carrier then the latest was the 9 5/8" carrier. These changes reflect Dodge engineering attempts to strengthen the 3/4 ton WC diff through time. The 8 3/4" 2 pinion carrier was used in the 1/2 ton WC in addition to front axles on earliest 3/4 ton WCs. The 8 3/4" differential had a short life in the 3/4 ton WCs due to strength issues.
VPW sells both the 2 and 4 pinion 8 3/4 carriers. Here is their catalog description:
•8 3/4” - 4 Pinion Vehicle Type: B
Part #CC927836, CC925727 $250
•8 3/4” - 2 Pinion Vehicle Type: A,(B early-front only)
Part #CC856853 $250
VPW also lists a 8 3/4" 5.83 ring and pinion set in there online catalog.
NOS Small 8 3/4” 5:83 for early 3/4 ton WC models
Part #CC922847 $200
Go to the following link to find these:
https://www.vintagepowerwagons.com/_files/ugd/a95fd2_d0c78867cd8c4d669469f2d71ade5982.pdf?index=true