STOPPED IN TRAFFIC ON A SLIGHT DOWNGRADE FOR A LONG PERIOD OF TIME. BRAKE PEDAL WAS APPLIED FIRMLY, WHEN THE TRUCK IN FRONT OF ME WOULD RELEASE THE PEDAL SLIGHTLY TO ALLOW THE CAR TO DRIFT FORWARD. AFTER SEVERAL TIMES THERE WERE NO BREAKS AND THE CAR DRIFTED INTO THE TRUCK IN FRONT OF US. HAD CAR BACK TO DEALER 2 TIMES THEY CLAIM THEY CAN'T FIND ANYTHING WRONG WITH IT.