Dana 44 swap/gearing help

[cobinder]

Ok guys maybe this is an easy one. My 80 GMC 3/4 ton dana 44 has a bad housing. I picked up a dana 44 out of 3/4 ton 75 Chevy to swap out with. My 80 comes with a 4:56 ratio, the 75 has a 4:55 in it. My corp 14 rear has a 4:56 in it. I'm I dreamin to use the 4:55 and just slide the assembly under my springs and be driven in an afternoon? Or do I have to swap my guts to the 75 housing. Or do I have to find a 4:56 ratio that fits the 75 diff?

Any insight would be greatly helpful

[b454rat]

Those are the same gears. Your allowed 2% difference between front and rear. If the donor axle has 4.56s put it in and run it.

[cobinder]

How the heck do they change the ratio .01 without a completely different gearing combo? Or maybe they just rounded off LOL

thanks 454

[trkklr77]

are you sure its even a d44 in a 80? not unless some one put it there.



you are fine with the .01 off ratio, especialy being slightly faster in the front, it helps turning and whips the front around mudding.

[kwmech]

Factory 1980 will be a corp 10 bolt in the front

[trkklr77]

Originally Posted by kwmech

Factory 1980 will be a corp 10 bolt in the front

hey hey !!!!! glad to see im not th eonly pbber on here!!

[cobinder]

I looked up the Bill of materials # off my 80 axle on the Dana website and it confirms it is a 44.
These two axles look the same except the donor has the spicer 44 big ole hubs.


FYI Dana's site is pretty informitive.

www2.dana.com/expert

Time to cleaning and unboltin

thanks for the input