Need help identifying 1972 k20 rearend.
 

The front axle is a Dana 44 and the numbers were easy to find. Not having any luck with the rear. I believe it to be the factory axle, but can't find any markings. Thanks for the help.

Re: Need help identifying 1972 k20 rearend.
 

That's An Eaton

Re: Need help identifying 1972 k20 rearend.
 

On the drivers side of the pinion on the front if there is a bolt with a jam nut. the bolt would be pointing towards the drivers tire. It is a HO72 if it does not have that bolt and nut it's a HO52.

Re: Need help identifying 1972 k20 rearend.
 

All HO72s (1-ton trucks) have the load bolt.... some HO52s (3/4-ton trucks) have it, and some do not. :chevy:

Re: Need help identifying 1972 k20 rearend.
 

Stocker, how do you tell them apart if it is a 52 with a preload bolt?

Re: Need help identifying 1972 k20 rearend.
 

Well, the hard parts are supposed to be mostly the same. Only difference I am aware of is the brakes, which are bigger on HO72s. And possibly some bearings, but a search is needed to find that info.

Re: Need help identifying 1972 k20 rearend.
 

They are the same rear with different brakes and wheel bearings. I'm sure it's the HO52 Corporate rear since that's what would have come in your K/20. Sure,maybe someone changed it. But they are the same rear anyway. The only HO72 it could be would be from a single wheel C/30. Very few cab & chassis SRW C/30s were sold, mostly stepsides and Longhorns

Re: Need help identifying 1972 k20 rearend.
 

It is original to the truck, so that would make it the HO52. I would like to change out the diffs from 4.10 to 3.73, but it doesn't look that easy with the HO52. Dana 44 up front.

Re: Need help identifying 1972 k20 rearend.
 

Not always true from everything i have read on this forum.. EDIT: Never mind i see it was already talked about.. :)

Re: Need help identifying 1972 k20 rearend.
 

I would really like to see some pic's of the HO-72 brakes, My K20 has the larger finned drums so i origionally thought it was an HO-72.