I am installing a 4:10 gearset in an 8-1/4 rear end with a suregrip.

The problem I have is that a special crosspin shaft is required. The Mopar performance catalogue doesn't list this part. I vagely recall reading somewhere about modifying a standard crosspin.

Doe anyone know where I can obtain this speical crosspin or how I can modify a standard one?

Not sure where you can find a new "dished" or "scalloped" cross shaft for your 8&1/4, but I'd suggest you first try to use the stock one with the 4.10 ring gear. There is enough variation in these carriers/gearsets that the clearance might be enough for use of the stock shaft.

If not, however, you can modify the stock shaft very easily: grind down the center of the shaft on one side, 90 degrees from the pin hole, to ~2/3s of its original thickness, for ~1&1/2" in length, tapering the edges to meet the full shaft diameter. When finished the shaft will need to have a "machined flat" in its center at least as long as the axle button diameter. Then polish the shaft with emery/crocus so that it slips & turns easily in the differential carrier.

For the axle assembly: do make sure this special shaft is already in-place before you mount the ring gear on the carrier. Install the carrier into the housing, establish the necessary side bearing preload, & when satisfied, install each axle after turning the shaft so that the machined flat faces the axle button. Put on the c-clip, push the axle into the side carrier gear, rotate the shaft so that the flat faces the other side, & repeat. When both axles are in-place, rotate the shaft to align the retainer bolt hole, insert same & you're done. Good luck!

good stuff ... archive material , never heard of doing that ...

Thanx for the reply, I did some searching on the internet and came ac ross a desciption in the Randy's ring and pinion site. Go to the following URL www.ringpinion.com/tech/techg0300.html

R