WE BY A 2007 SILVERADO , IN BROWNSVILLE TX, 2008 NEW , ABOUT 5000 MILES START W/ PULSATION AND BRAKE PROBLEMS, WE TAKE TO THE DEALER AND THEY CHANGE 3 TIME THE DISC BRAKES, AND BRAKES PADS ,, TIRES AND CHIMES AND STILL HAVE THE SAME PROBLEM. W THIS TRUCK ITS A 4 DOORS TRUCK WHEN YOU PRESS THE BRAKE ANY SPEED DO THE PULSATION AND MAKE A LOUD SOUND WHEN PRESS HARD THE BREAKS MY WIFE HAS A ACCIDENT IN DECEMBER 2008 IN MEXICO SHE SAID SHE PRESS THE BRAKES HARD AND DO NOT STOP SHE STOP W/ THE OTHER TRUCK SHE CRASH,, SHE DON'T HAVE ANY INJURIES ,, ANY SUGGESTION ABUT THIS PROBLEM ??? *TR