VEHICLE DESCRIPTION: CLASS 8 HEAVY DUTY TRUCKS. THE AIR SUSPENSION CONTROL VALVE SUPPLY LINE WAS NOT PLUMBED THROUGH AN AIR PRESSURE PROTECTION VALVE. IN THE EVENT OF A FAILURE, THERE WOULD BE LOSS OF AIR PRESSURE IN THE 'B' SYSTEM AIR RESERVOIR THAT SUPPLIES AIR PRESSURE FOR THE FRONT STEER AXLE BRAKES.
Consequence & remedy
Consequence: THIS CONDITION WOULD RESULT IN INCREASED STOPPING DISTANCES.
Remedy: DEALERS WILL INSTALL THE NECESSARY AIR PRESSURE PROTECTION VALVE.
THE TRACTION SOLENOID EXHAUST CAN BE OBSTRUCTED DUE TO INADEQUATE DRAINAGE AND A BUILD-UP OF ROAD CONTAMINATION BETWEEN THE MOUNTING BRACKET AND THE SOLENOID HOUSING. THE OBSTRUCTED EXHAUST PREVENTS THE RELAY VALVE CONTROL AIR PRESSURE FROM VENTING AFTER A DIFFERENTIAL BRAKING TRACTION EVENT.
Consequence & remedy
Consequence: THIS CONDITION WOULD KEEP THE REAR AXLE SERVICE BRAKES APPLIED WITHOUT ANY BRAKE PEDAL MOVEMENT BY THE DRIVER INCREASING THE RISK OF A VEHICLE ACCIDENT.
Remedy: DEALERS WILL REMOVE THE SUSPECT VALVE AND INSTALL A NEW VALVE THAT HAS A MODIFIED SOLENOID HOUSING WHICH WILL ALLOW FOR SUFFICIENT DRAINAGE AND A NEW VALVE MOUNTING BRACKET WITH INCREASED HEIGHT TO REDUCE ENTRY OF CONTAMINATION.
UNDERCOATING APPLIED TO THE INSIDE OF THE CAB SHELL SQUEEZED OUT DURING ASSEMBLY ONTO THE BRAKE PEDAL PLUNGER.
Consequence & remedy
Consequence: UNDERCOATING ON THE PLUNGER MAY CAUSE THE PLUNGER TO STICK RESULTING IN INCREASED BRAKE PEDAL EFFORT AND/OR SLOW RELEASE OF THE BRAKES INCREASING THE POTENTIAL FOR A VEHICLE ACCIDENT.
Remedy: DEALERS WILL CLEAN THE UNDERCOATING FROM THE BRAKE PEDAL PLUNGER ASSEMBLY, LUBRICATE AND REINSTALL THE BRAKE PEDAL PLUNGER ASSEMBLY.
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