My wife's 01 Yukon XL has had this extreme "popping sound " thats has progressively gotten worse. She has been backing out at the grocery store and thought she either ran over something or hit a buggy only to get out and fi.d there's nothing there. . As a passenger I've heard it a couple times, but I rarely drive it. I got in it this morning and "POW !!!! " it felt at sounded like a wheel just snapped off at the hub , but I saw nothing out of the ordinary. So I went to pull it back into the carport and POW !!! POW !! About every other rotation of the wheel it would pop again. Not like your pop from cv or ball joints (at least not like any Ive ever heard) , but a violent soun along qwith feeling like you ran over something. I can't pinpoint front or rear , left or right. My wife thi.ks front driver and I think somewhere on passenger. Any help with this would be greatly appreciated. This is our main means of transportation and I need to fix it this weekend. I have a full suspension kit, but not about to rebuild entire suspension today...unless necessary. I would really like to narrow it down to the immediate cause of this problem. Thanks again for taking the time.