About a week ago my truck started making a high pitched click/clunk sound when i first take off. Seems to have somewhat excessive gear backlash. I'm a mechanic but unfortunatly have never had to much experiance with diffrentials. The other thing i noticed when i changed the rear u-joint is that gear oil is seeping out from the inside of the pinion yoke, not around the seal. What could cause this. All the bearings feel tight and it turns smooth without any binding.

Any input is appreciated.

Thanks,
Josh

This is a 2003 f150 with the 8.8 and limited slip