There are 2(at least) sub part numbers for the 5-7166x u-joint.
On the wrong part number(the most prevalent) the center cross casting interferes with the yokes on the drive shaft and you cant even install it. Spicer knows about this and has a re-designed part number out there. You have to know somebody who actually will go look at the parts.
Im not USUALLY a fan of WAL, but they were the forum talking about this issue when I tried to install new 5-7166x u-joints last month and we couldnt even get them into the yokes. U-joints won't fit!!
On mine, the end caps were the right diameter. I was able to press the inner axle caps in without incident. When I went to press the outer axle caps on, I got the first one into place and clipped it, but when I was pressing the opposite one into place I couldn't get it far enough in to secure it and drove the joint right through the opposite end cap with a very loud bang when it let go.
Just so that there is no confusion, I did get a new axle, complete and it has been in place and running since I posted this thread. The casting number that has the problem is 2002422GJ. The number is on the axle half that contains the stud flange. The number on the casting is close to the yolk end of the axle half.
A forum community dedicated to Jeep Wrangler owners and enthusiasts. Come join the discussion about reviews, performance, trail riding, gear, suspension, tires, classifieds, troubleshooting, maintenance, for all JL, JT, JK, TJ, YJ, and CJ models!