United States 98V003000
FREIGHTLINER LLC
The problem
VEHICLE DESCRIPTION: TRUCK/TRAILERS EQUIPPED WITH A HYDRAULIC PARKING BRAKE. A CASTING ERROR IN THE HYDRAULIC PARKING BRAKE RELAY VALVE CAUSES EXCESSIVE PRESSURE IN THE BRAKE SYSTEM WHICH CAN RESULT IN A HYDRAULIC HOSE SEPARATION.
Risk
IF THIS OCCURS, THE POWER STEERING ASSIST WILL BE LOST AND THE BRAKES WILL BE OPERATING FROM THE BACK-UP SYSTEM.
What owners should do
DEALERS WILL INSTALL A CHECK VALVE MODIFICATION KIT TO REDUCE THE SYSTEM PRESSURE.
Units 2587