My LJ came from the PO with an aftermarket rear driveshaft (mfr unknown) with the Glidecoat. It also came with the wrong size U-joint installed at the pinion end (I was shocked because I drove 12 hours home with that!) When I pulled the shaft at the rear U-joint to replace it, I discovered that the Glidecoat was causing the driveshaft to bind - it took an incredible amount of beating to separate the two.
When I looked into the cause of the binding, the Glidecoat was peeling, and just like in the link freedom_in_4low posted, Shawn said that was pretty rare. I told Shawn that I’m not yet ready to replace it because I have a Savvy mid-arm kit, with new Currie springs, waiting to be installed, and I expect to need a different length driveshaft. He told me to just remove all the Glidecoat to free it up, and after, to keep it greased regularly. He even sent me a new cap with a zerk for the end of the female-splined section so that I can keep it greased - for free! There’s now a lot of free play in the joint, but I’m not worried because I really won’t be driving it much until I get the mid-arm installed and replace it.
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