suspect the half shafts before the diff. the diffs are extremely long lived. check out the half shafts. park the car with it in nuetral and held by the parking brake and reach up and grab the half shaft and see if it will wiggle. it shouldnt at all.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.