Eaton GM 8.5 10 bolt Posi Rebuild ?? What Clutch Disc sets to use?


Active Member
Have a 10 yr old Eaton 10 bolt posi I',m looking into rebuilding. Per Eaton Tech there are (3) different sets of clutch packs that they offer for this service of the Posi

1. P/N 29-426-00S 14 Pack Carbon Composite Disc set $150
2. P/N 29-403-00S 18 Pack Steel Disc Set $133
3. P/N 29-402-00S 22 Pack Steel Disc Set $143

Doing some Google searches some people have had chatter issues with #2/3 above even with Diff additive-

Has anyone rebuilt their Eaton 10 Bolt 8.5 Posi lately? What Disc set did you use? Any guidance or issues with either sets you can report??

Also going to replace the preload service spring kit-29-590-00S-$46.00

They offer a #400 pound version and an #800 pound option.

All parts listed are available thru Summit Racing.

Anyone have any feedback on their rebuild and what was used and how its performing to date?


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Well-Known Member
Pretty simple. I'm pretty sure you can do it without removing the case. I had mine out since I was replacing the ring and pinion. If you have to remove it make sure you don't mix up the shims on the sides of the case.


Active Member
I did mine in a afternoon without removing the center section, rolling around on the garage floor.
I should have supported the car and let it hang from the shocks, would have gave me more room, my jack stands were just the short set. This was a OEM Eaton.