I own a 1998 Olds Aurora,130,000 Miles,Auto,4.0 that is barely using the front brakes, any abrupt braking will warp both rear rotors. The pads are contacting the outside of the front rotors but just slightly on the inside. I have removed the anti-lock fuse to see if it was a problem in the anti-lock system but it made no change, might it be a proportioning valve. I work with professional mechanics daily and they havent a clue where to start with this problem