Alright Im hoping someone can help me figure this out. Its on a 2000 xj with a dana 30. for the past month or so ive noticed i had a sound when turning like this knock knock knock knock it only has been happening sometimes. I opened up the front diff today and found that if I take the passenger tire and spin it very slow (jacked up) that it would sometimes dothe knock knock thing it felt like the tire was binding up in the axle housing. i removed axle checked u-joints and bearing they are fine, so i looked a little better at the gears and you can see where the spider gears are actually scratched and ou can feel the scratches with your finger. also the pinion shaft has about 1/4" of what looks to be almost burnt metal on what i think is the coast side ofthe gear. the ring gear is also wearing a little to where it almost feels sharp to the touch. I will post some pictures tomorrow to try to better explain it. thanks