THE VEHICLE BRAKING SYSTEM BECOME RIGID AT LOW SPEED (APPROX 3MPH OR SO) AS IF THE POWER BRAKE SYSTEM FAILS. THE VEHICLES STOPPING DISTANCE CHANGES AND THE VEHICLE CONTINUES TO ROLL WHILE PRESSING THE BRAKE PEDAL TOWARD THE FLOOR. THIS ISSUE RESULTED IN DAMAGE TO MY GARAGE DOOR WHILE BACKING THE VEHICLE INTO THE DRIVEWAY. THE ISSUE IS BEST DESCRIBED IN THE PENDING INVESTIGATION REGARDING THE GM BRAKING SYSTEM LOCATED UNDER CHEVROLET SILVERADO RECALLS. I WAS MADE AWARE OF THE INVESTIGATION AFTER RESEARCHING THE ISSUES I HAVE HAD WITH MY VEHICLES BRAKES. THE INVESTIGATION STATEMENT DESCRIBES THE ISSUE AS A PROBLEM WITH DEGRADING BRAKE VACUUM COMPONENT.