I HAVE HAD THE BREAK/STEERING FLUID BOOSTER REPLACED 3 TIMES IN A 6 MONTH PERIOD. HOW GMC CAN CALL THIS A "PROBLEM" BUT NOT A SAFETY ISSUE IS BEYOND ME. I HAVE LOOKED IT UP AND THOUSANDS HAVE HAD PROBLEMS WITH THIS ALONG WITH ALIKE VEHICLES FROM THE SAME YEARS. THE BREAKS AND STEERING LOCK UP WHILE DRIVING ESPECIALLY AROUND TURNS. IT IS EXTREMELY DANGEROUS!!!!! I GUESS NOT ENOUGH PEOPLE HAVE DIED....UUGGHHH .... SO FRUSTRATING!!!!