just for ****s and giggles disconnect the speedo cable i think it runs up that side of xj cant hurt see if noise gos away

where should i disconect it from. wouldn't it leak out transfercase fluid if disconected underneith

no just unscrew the big nut on the transfer case let it hang and test drive maybe the cable is fraying inside the housing and causing the cable to thump ?

will try that tonight thanks

sometime you have to figure out whats not making a noise to find out what is lol

speedo cable is not it, although i got to mess with it more tonight the ball joints did help a little and if i turn left just right the noise goes away or at least gets quieter.

Pull both front wheels off and turn the hub by hand- if you feel any grinding....Bingo....Hub unit.

replaced the front hub today works great now, thanks for everyones help

I am Having the Exact!! same problem in My XJ Did you figure out what it was???

sorry this is so late but yes it was the front hub