1997 Volvo Wah

Component: SERVICE BRAKES, AIR:ANTILOCK

VEHICLE DESCRIPTION: HEAVY DUTY TRUCKS BUILT WITH BENDIX AIR ABS WITH AN EC-17 1030R ELECTRONIC CONTROL UNIT (ECU), THERE HAVE BEEN REPORTS OF UNWANTED ABS ACTIVATION AT LOW SPEEDS CAUSED BY 1) CHAFED ABS WHEEL SPEED SENSOR WIRES ON ROTATING PARTS OR 2) A DAMAGED COMPONENT AT THE WHEEL END THAT GENERATES A CERTAIN TYPE OF ERRATIC SENSOR SIGNAL.

Consequence: THIS CONDITION COULD CAUSE THE ABS ECU TO EXHAUST THE AIR AT THE AIR BRAKE MODULATORS FOR ONE OR MORE OF THE WHEELS. THIS COULD RESULT IN EXTENDED BRAKING DISTANCES AND A POSSIBLE CRASH.

Remedy: DEALERS WILL REPLACE THE ABS ECU.

Component: WHEELS:RIM

VEHICLE DESCRIPTION: HEAVY DUTY TRUCKS EQUIPPED WITH AFTERMARKET ALUMINUM DUAL WHEELS, 22.5X8.25, ONE-PIECE, TUBELESS, SUPPLIED BY ACCURIDE/AKW. CERTAIN DESIGN REVISIONS COMBINED WITH PROCESS CONDITIONS CAUSED FATIGUE CRACKS IN THESE WHEELS.

Consequence: THIS CONDITION CAN CAUSE FAILURE OF THESE WHEELS.

Remedy: ACCURIDE/AKW WILL REPLACE THESE WHEELS.

Component: SUSPENSION:FRONT:SPRINGS:AIR SUSPENSION:LINES AND FITTINGS

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: THIS CONDITION WOULD RESULT IN INCREASED STOPPING DISTANCES.

Remedy: DEALERS WILL INSTALL THE NECESSARY AIR PRESSURE PROTECTION VALVE.

Component: SUSPENSION:FRONT:WHEEL BEARING

VEHICLE DESCRIPTION: CLASS 8 HEAVY DUTY TRUCKS. THE STEER AXLE WHEEL BEARING JAM NUT LOCK WASHER MAY NOT HAVE BEEN BENT OVER THE JAM NUT AFTER THE WHEEL BEARINGS WERE ADJUSTED.

Consequence: IF THIS CONDITION EXISTS, THE JAM NUT AND WHEEL BEARING ADJUSTING NUT CAN BACK OFF THE SPINDLE ALLOWING THE WHEEL AND THE BRAKE DRUM ASSEMBLY TO SEPARATE FROM THE VEHICLE INCREASING THE RISK OF A VEHICLE CRASH.

Remedy: DEALERS WILL INSPECT THE STEERING AXLE WHEEL BEARING JAM NUT LOCK WASHER TO DETERMINE IF IT IS BENT OVER THE JAM NUT, AND IF NOT, REPAIR AS REQUIRED.

Component: PARKING BRAKE

VEHICLE DESCRIPTION: HEAVY DUTY TRUCKS EQUIPPED WITH HALDEX MANIFOLD DASH VALVES (MDV) USED IN TRACTOR AND TRAILER PARKING BRAKES. THESE VALVES DO NOT MEET THE REQUIREMENTS OF FMVSS NO. 121, "AIR BRAKE SYSTEMS." A LOSS OF THE ISOLATION OF THE TWO BRAKE SYSTEM CIRCUITS CAN RESULT IN THE LOSS OF SERVICE BRAKES WHEN THERE IS ANOTHER FAILURE OF ONE OF THE TWO BRAKE CIRCUITS.

Consequence: THE LOSS OF SERVICE BRAKES CAN OCCUR, INCREASING THE RISK OF A CRASH.

Remedy: DEALERS WILL REPLACE THE SUSPECT VALVES.