exactly why i said he needs less backspacing if he's rubbing the CA's.Backspacing:
Higher number=wheels under jeep, higher BS moves wheels to middle of jeep.
Lower number=opposite of above, lower moves wheels out from jeep.
OK take your front end and use a jack to place it on stands with 2-3" of clearance between the tires and the ground or do this one side at a time with just the jack. Take a long pry bar or something long and metalic that will not bend and will fit under and give you leverage. With someone watching the ball joint in question lift up on the pry bar and release (up and down) if any movement is noticed then you have a bad Ball Joint. Also you can stick a hand at twelve O'clock and one at six O'clock and trie and jiggle the wheel from top to bottom. ANY mocvement at all is bad.I have 4 inch's of BS. There is no rubbing, I have plenty of room under there. I believe the popping is coming from the passenger side ball joint(upper).