For the bearing caps holding the posi unit in. Is it worth it for added strength to use a stud kit over the standard bolts for the diff caps?
I've seen aftermarket caps as well, but they specify needing machining to fit???

I guess the studs would be stronger. The after market steel caps don't need a lot of machine work. You just have to face the mating surface so that the bore is round. This can easily be done on a mill. You only need a steel cap on the left (ring gear) side.

You just have to face the mating surface so that the bore is round.
That is what I understood from reading the info about them, but why don't they just come the right side to begin with? Can't they just be dimensionally the same as an OEM cap?
What exactly do you do to determine how much to take off of the caps? I keep thinking of this like rod caps, but that is the opposite....you mill them to make them not round and then hone them out to make them round again. :confused: I'm confused, but then again, that's normal when it comes to anything inside of that 12 bolt cover.

Whwn you buy a billet aluminum or steel cap, they come with a little more material on the machined face to be custom fit. Due to the casting of the housing, when G.M. machined the bores inside the housing, they are not in the sam eplace on every rear. The bores are machined with the factory caps on, so if you replace the cap, the cap has to be custom fit to the original rear with the bearing race installed.

I went with the Billet cap on the drivers side where all the load takes place, the cap came with 1/2" bolts that required a redrill and tap of the housing. It has worked for me so far. I would say this is probably the best mod you can do the the 10-12 bolt rears. Studs would help a little, but a billet cap AND oversized 1/2" studs would really be the way to go!!

Jim if it helps any, I have the Strange billet aluminum caps and the bolts they came with. They've been in the car for 11 years and I think I hit them pretty hard.

Ray, yea,...I have seen the pic of you car launching, I'd say you hit it pretty hard. :yes:

The housing has the caps installed before the bearing bore is machined. This way the bore is round. If you swap caps then the bore is no longer round, just like the main bearing bore in an engine block. The after market caps are made so that you can cut a little off of the mating surface to get the correct round bore that you need. You can install the cap and measure the bore to see how much material needs to be removed from the mating surface.

Thanks for clearing that up guys. I wonder where I can get just one cap instead of a pair to save a few bucks since it is only necessary on the driver side of the case.

Tom's Differentials sells the one billet cap and larger bolts for like $70 bucks.

I have done this conversion and use a milling machine to drill the oversize hole and tap. As for the hole being round the cap is already machined round and you are just removing a little material to make sure you have a crush on the bearing race. If you remove a little too much material the cap once installed is still round

I have done this conversion and use a milling machine to drill the oversize hole and tap.

Curious how you mounted the housing. I have access to a bridgeport and will perform this when the time comes.

Most places sell the caps individually. I don't know anyone who sells them in pairs. They know that the left cap is all that is needed.

Most places sell the caps individually. I don't know anyone who sells them in pairs. They know that the left cap is all that is needed.

:confused: I have a Strange and a Moser catalog and I see pairs. Here they are in Summit......Pair of diff caps (http://store.summitracing.com/partdetail.asp?autofilter=1&part=STR%2DH1121&N=700+317648+115&autoview=sku)

EDIT,.....Scotty above pointed out that Tom's differentials sells them individually, but that one requires 1/2" bolts. (more machine work,...$$$)

get them from mark williams enterprises. sold as singles. come with stock size bolts and good instructions. tom

Tom, thanks. I just ordered it from MW:)

My 2007 Moser catalog doesn't list bearing caps. Anyway, I know that MW sells singles. I think Tom's Differentials has them too.