To be honest, this was a false alarm. Jeep WK Propshaft Front. The front prop shaft was making funny clunking noises, so I assumed after reading up online that it was toast after 15 years. Basically the CV joints go, and with a 3″ inch lift there are extra stresses with the increased rotation angle. So I purchased a new one to sort out the problem. Jeep Club Etsy shop
My mechanic just took it off, took a good look, then just reinstalled the old one, it was just a little loose and bolts were not tight enough.
Moral: Seek professional advice before you buy new parts.