WildWillyWalker
Member
This is just making me feel stupid. My rearend was making noise so I was going to replace the bearings. the bearings pulled off the diff by hand and the diff surface was scored and pitted. This was the best time to upgrade to 31 spline axles. I got a 31 spline Trac Lok from Ford racing. It's the Cobra spec diff since it has carbon clutches. I got a ring and pinion install kit from cjponyparts (RPM2K). Installed a new pinion shim but the diff shims were aligned (we did check). The axles are 31 spline from Yukon. they're stock length. Got the abs rings swapped over and installed the axles. They're sticking out too far! I put the new Cobra rotors on and the caliper bracket won't reach the bracket on the axle. There is a good 1/8th space. I noticed the center pin in the diff is 1/8 thicker than my stock diff pin. This would account for 1/16th per axle. The cobra rotors are thicker than the stock rotors so there isn't much play for the rotor in the caliper bracket. My only fix is to get some washers or a piece of metal to space the caliper bracket out from the axle housing. I've never heard of such a problem and this just seems stupid. I don't know how I could have installed something wrong. I spent a while comparing the length of the old axles and the new ones and they seem almost perfect. The new ones might be 1/16th inch longer at most.