Trying to find the cherping brake pads and the back appears to be the problems. Pulled the wheels, note that the rear on my 01 burb takes a 12mm, unlike the fromt which takes the * socket. I have all four bolts broken loose but can not get any of them to back out, or tighten back up so it appears. It acts like a nut is turning on the other ebd, but is goes directly into the caliber support bracket. Anyone ever had issue with getting these bolts to back out ?