5-SPEED TRUCK PARKED ON STEEP D/W WITH PARKING BRAKE ON, FEW HOURS LATER PARKING BRAKE DISENGAGED BY ITS SELF AND ALLOWED TRUCK TO ROLL INTO GARAGE DOOR, D/W IS STEEP ENOUGH THAT TRUCH WOULD HAVE ROLLED IMMEDIATELY IF BRAKE WAS LEFT OFF BY ACCIDENT. DEALER COULD NOT REPEAT EVENT, BUT FOUND BRAKE CABLE A LITTLE OUT OF SPECS. *AK