12 bolt rebuild + eaton

[DavidB]

About four years ago I did a LS engine swap on this truck and have done way too many single tire burn outs and have been wanting to do a good posi ever since.
I have set up about a dozen rear ends and have never had a noise or problem with any of them (knock on wood). I'm going to do a simple how to on this with pictures to hopefully help some one here out. I'm no expert and any input is welcome.
The first thing you will notice when ordering parts is there is a 3 or 4 series. The 3 series is for 2.76 - 3.42 gear ratio and the 4 series is for 3.73 up. The difference is the thickness of the diff. The 3 series eaton is cheaper than the 4and you can order a "thick" 3.73 up gear to go on the 3 series.
My truck came with a 4 series 3.73 but since I'm doing a complete rebuild I orderd:
3 series eaton #19587-010 $425 Ebay
Motive gear thick 3.73 #mgr-gm12-3.73x $169 summit
rebuild kit # rat-3005k $109 summit
I decided to do the 3 series so I had the option of running any ratio with out replacing the most expensive piece.

[IMG]http://i859.photobucket.com/albums/ab159/dbright78/rearend037.jpg[/IMG]