i have a brand new auburn posi, and installation kit in boxes that my friend gave me. Problem is they're for his 1993 c1500 which has the 8.5 with the smaller carrier bearings in it. the parts were bought from summit one year ago, so i can't return them or swap them out for the bigger carrier bearing unit for my 8.6.

anyone work at a driveline shop that deals with auburn, and maybe be able to hook me up with the possiblity of a swapout? the stuff's absolutely brand new, in original packaging, uninstalled. I don't wanna sell them at discounted prices or ebay 'em. I'd like to just do an even swap if possible.

any help is appreciated.

 

it should still work. just buy the larger bearings and you'll be good to go.

 

It wont work. The inner diameter of the bearings is different as well as the OD. Also, they dont make a bearing to put the small hub case into the NBS truck, but they do make a bearing to put the large hub into older trucks.

 

then it's different from the eaton. my install kit cam with the pre 99 bearings. all i had to do was get the larger bearings and shims.

 

call keith at performance auto and trans 1 781 279 3233. He is out of stoneham i think. HE knows his **** and should be able to help you. Tell him Matt with the Red Dez Racing truck sent you.

 

The eaton has the larger hub diameter for the later trucks and the bearings to make it work in the older trucks(larger ID and earlier small OD). The bearing they include is not the factory bearing it is a hybrid with the late style ID and early style OD. His diff has the smaller hub like the old trucks, there is no way to make that work in the newer trucks. The newer trucks have a larger OD and ID. The Auburn Pro has the large hub diameter but the regular ones do not. You can put a new case(or eaton/auburn pro) in a old truck with the proper bearing, just not the other way.
Edit- the Eaton does not include bearings, the Auburn Pro does.

 

BTW- trust me- I do this stuff for a living. I could give you the bearing numbers off the top of my head-
lm501349 - pre 99 8.5
lm603049 99-up 8.6 (larger ID and OD than early 8.5)
lm102949 early ID late OD
I might be 1 digit off, but that should be close. Maybe an 8 instead of a 9 or something.

 

If you do this stuff for a living...... can ya help me out? lol

 

I would if we werent wholesale only. We only sell to distributors.