SERVICE BRAKES, HYDRAULIC:FOUNDATION COMPONENTS:DRUM
THESE VEHICLES HAVE FRONT AXLES WITH BRAKE CAM OPERATION OPPOSITE TO THE ROTATION OF THE BRAKE DRUM (CAM OPPOSITE), AND THERE IS A TENDENCY FOR BRAKES TO CHATTER UNDER LOW AIR PRESSURE, RESULTING IN VIBRATIONS. THE VIBRATIONS INDUCE STRESSES IN THE TIE ROD END BEYOND ITS ENDURANCE LIMIT, AND RESULT IN CRACKS IN THE THREADED PORTION OF THE STUD WHERE THE TUBE ENDS.
Remedy: REPLACE THE CAM OPPOSITE BRAKE ACTUATION WITH CAM SAME BRAKE OPERATION, BY INTERCHANGING THE LEFT AND RIGHT CAM ASSEMBLIES TO AVOID BRAKE CHATTERING; AND REPLACE TIE RODS.
130 vehicles affected