I'm looking to get an Eaton posi unit for my 04 GMC,5.3,auto,RC/SB 1/2 ton,4x4. Can anyone tell me which housing I have, or better yet exactly which posi unit I would need? Thanks

 

I'm pretty sure this is the one you want.

http://cgi.ebay.com/ebaymotors/ws/eB...RK%3AMEWA%3AIT

.. I know it's Ebay, and the auction is already closed, but what are ya gunna do

 

Thanks for the help! That looks to be what I need. I wasn't sure exactly which housing I have in my truck.

 

you have the 10 bolt 8.5 inch.

i believe it is 30 spline.

you need:

- posi
- carrier bearrings
- shim kit (i reused stock shims)
- GM 10 bolt 8.5" gasket
- gear oil
- red threadlock

 

Would I be any better off with synthetic lube in there?

 

whats the diff between the eaton and the G80?

 

the G80 comes as an option from GM. it is similar to posi where the rear axle locks up and the 2 rear tires spin together instead of the one-wheel-peel. the difference that i know of is that the G80 unlocks over 20 mph, where the Eaton is locked at all speeds. there are benefits and downfalls for both. the unlocking of the G80 is good in rain and snow at higher speeds because it keeps you from fish tailing and losing control when you give it gas. now the Eaton does help at higher speeds though. you are less likely to break that one tire loose at higher speeds. it all depends on the driving situation.

overall, i would definitely choose the Eaton over the G80

 

this has been i big debate between me and the rest of the guys here. i have been told by the most popular Eaton dealers to use 85/140 synthetic. everyone else here disagrees and says use 80/90 or whatever it is, with the GM additive.

i'll let you make the choice.

but i have been told that the 85/140 works the best, especially since there is a carbon fiber clutch in the Eaton. nice thing about this posi is that it is rebuildable

 

thx for the info. I have the G80, just thinking if its worth it to replace it with a different locker.

 

since you have the G80 already... I'd look into a tune and/or a stall TC instead... just my opinion