1980 Mack U Series Recalls

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NHTSA Campaign Number: 82V019000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: April 1st, 1980
Manufactured End Date: January 1st, 1982
Date of Owner Notification: February 24th, 1982

Defect Summary:
CERTAIN VEHICLES MAY BE SUBJECT TO STEERING SHAFT SEPARATION DUE TO LOOSE SET SCREWS IN THE DASH SHEET BEARING WHICH MAY ALLOW THE SHAFT TO MOVE.

Corrective Summary:
DEALER WILL INSPECT AND MODIFY THE STEERING SHAFT BY PROVIDING A GREATER SLIP LENGTH IN THE STEERING DRIVE SHAFT TO ELIMINATE SLIP JOINT SEPARATION.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS EQUIPPED WITH SGP5/ROSS STEERING GEAR.SYSTEM: STEERING; STEERING SHAFT SLIP JOINT.CONSEQUENCES OF DEFECT: STEERING SHAFT DISENGAGEMENT DURING VEHICLE OPERATIONMAY CAUSE LOSS OF STEERING CONTROL AND A VEHICLE ACCIDENT.

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NHTSA Campaign Number: 81V088000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: July 1st, 1979
Manufactured End Date: January 1st, 1980
Date of Owner Notification: December 21st, 1981

Defect Summary:
THE RETAINING PIN FOR THE BRAKE CONTROL KNOB HAS BEEN MISALIGNED (OFF THE CENTER LINE OF THE VALVE PLUNGER HOLE). THIS CAUSES THE KNOB TO BE OVERSTRESSED AT THE RETAINING PIN HOLE AREA CAUSING IT TO SEPARATE FROM THE VALVE.

Corrective Summary:
THE HOLES WILL BE RETOOLED TO PROVIDE CORRECT ALIGNMENT AND PLASTIC KNOBS WILL BE REPLACED BY KNOBS OF STRONGER MATERIAL HAVING METAL REINFORCEMENTS.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS EQUIPPED WITH BRAKE CONTROL KNOBS.SYSTEM: SERVICE BRAKES; KNOB RETAINING PIN.CONSEQUENCES OF DEFECT: WITH THE KNOB BROKEN OFF, THE CONTROL VALVE WOULDBECOME DIFFICULT OR IMPOSSIBLE TO OPERATE. ONE OR A COMBINATION OF BRAKEAPPLICATIONS WOULD NOT BE POSSIBLE AND THE VEHICLE COULD BE PARKED IN AN UNSAFECONDITION. AN ACCIDENT AND PERSONAL INJURY COULD RESULT.

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NHTSA Campaign Number: 80V052000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: July 1st, 1979
Manufactured End Date: January 1st, 1980
Date of Owner Notification: October 20th, 1980

Defect Summary:
ON CERTAIN VEHICLES, THE KNOB THAT OPERATES THE TRACTOR PARK VALVE MAY BREAK OFF, RENDERING THE VALVE INOPERABLE.

Corrective Summary:
DEFECTIVE KNOBS WILL BE REPLACED WITH AN IMPROVED TYPE, WITHOUT CHARGE TO OWNER.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS.SYSTEM: SERVICE BRAKES; TRACTOR PARK VALVE CONTROL KNOB.CONSEQUENCES OF DEFECT: THE PURPOSE OF THE TRACTOR PARK VALVE IS TO ALLOW THEDRIVER TO APPLY THE TRACTOR SPRING EMERGENCY/PARKING BRAKE INDEPENDENTLY OF THETRAILER EMERGENCY PARKING BRAKES. IF THE KNOB IS BROKEN, THE TRACTOR PARKINGBRAKES CANNOT BE APPLIED. IF PARKED ON AN INCLINE AND LEFT UNATTENDED, VEHICLECOULD ROLL FREE AND CAUSE ACCIDENT AND INJURY.

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NHTSA Campaign Number: 80V054000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: July 1st, 1976
Manufactured End Date: January 1st, 1980
Date of Owner Notification: January 31st, 1981

Defect Summary:
THE PREFABRICATED PINCH BOLT CLAMP AT THE LOWER STEERING SHAFT LOWER YOKE MAY NOT PERFORM ADEQUATELY WHEN TIGHTENED TO SPECIFICATIONS. THE CLAMP MAY THEN DEFORM AND LOSS OF CLAMPING FORCE AND STEERING SHAFT DISENGAGEMENT MAY RESULT.

Corrective Summary:
DEALER WILL RETROFIT WITH LOWER STEERING SHAFT LOWER YOKES THAT PROVIDE FOR INTEGRAL PINCH BOLT INSTALLATION IN PLACE OF PREVIOUS SEPARATELY FABRICATED CLAMP FOR THE PINCH BOLT.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS.SYSTEM: STEERING; POWER STEERING SHAFT; FABRICATED PINCH BOLT CLAMP.CONSEQUENCES OF DEFECT: DISENGAGEMENT OF THE STEERING SHAFT MAY CAUSE LOSS OFVEHICLE CONTROL WITHOUT PRIOR WARNING AND, POSSIBLY, AN ACCIDENT.