United States 79V059000
PACCAR Incorporated
The problem
THE PARKING BRAKE VALVES MAY HAVE BEEN INCORRECTLY PIPED. IF THE PARKING BRAKE PIPING IS INCORRECTLY ROUTED, THERE IS NO WAY TO SET THE TRACTOR PARKING BRAKES INDEPENDENTLY OF THE TRAILER PARKING BRAKES. THIS COULD CAUSE THE PARKING BRAKES TO BACK OFF WHILE THE TRAILER AIR SUPPLY IS BEING CHARGED, CAUSING THE TRACTOR TO ROLL.
What owners should do
TRAILER AIR SUPPLY WILL BE MOVED FROM THE DISCHARGE SIDE OF THE TRACTOR PARKING VALVE TO THE DISCHARGE SIDE OF THE COMBINATION PARKING VALVE. THIS SERVICE WILL BE DONE AT NO CHARGE.
Units 2620