1980 Mack Ms300p Recalls

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NHTSA Campaign Number: 82V054000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: July 1st, 1979
Manufactured End Date: May 1st, 1982
Date of Owner Notification: November 24th, 1982

Defect Summary:
THE CIRCUIT WIRING ON THESE VEHICLES IS ARRANGED SO THAT A SHORT CIRCUIT IN THE REAR TAILLIGHTS WILL ALSO RESULT IN LOSS OF POWER TO THE HEADLAMPS. FOR SAFETY REASONS THE LIGHTING SYSTEM WIRING SHOULD BE INDEPENDENT.

Corrective Summary:
VEHICLES WILL HAVE AN AUTOMATIC RESET CIRCUIT BREAKER INSTALLED TO ENSURE CONTINUED HEADLAMP ILLUMINATION IN THE EVENT OF A SHORT IN OTHER LIGHTING SYSTEMS.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS.SYSTEM: LIGHTING; HEAD LAMP WIRING.CONSEQUENCES OF DEFECT: SIMULTANEOUS LOSS OF BOTH TAILLIGHTS AND HEADLAMPSDURING NIGHT DRIVING COULD RESULT IN A HEAD-ON OR REAR-END COLLISION.

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NHTSA Campaign Number: 81V157000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: September 1st, 1979
Manufactured End Date: August 1st, 1981
Date of Owner Notification: August 12th, 1982

Defect Summary:
WHEN THE IGNITION KEY IS IN THE "ON" POSITION AND THE HEATER IS OPERATING AT THE "LOW" OR "MEDIUM" SETTING, THE HEATER SWITCH WIRING WILL OVERLOAD IN THE EVENT THE HEATER MOTOR SEIZES.

Corrective Summary:
A SPEED VARIATION RESISTANCE UNIT AND AN ELECTRIC MOTOR MOISTURE PROTECTION CAP WILL BE INSTALLED WITHOUT CHARGE.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS.SYSTEM: HEATING; CAB HEATER MOTOR, ELECTRICAL SWITCH.CONSEQUENCES OF DEFECT: IF THE VEHICLE IS STANDING STILL (PARKED OR STOPPED INTRAFFIC) HEAT GENERATED BY THE OVERLOAD MAY MELT AND IGNITE THE SURROUNDINGPLASTIC HOUSING AND WIRE COVERING. A FIRE COULD SPREAD QUICKLY THROUGHOUT THECAB, CAUSING SERIOUS INJURY TO VEHICLE OCCUPANTS.NOTE: OWNER IS ADVISED TO MAKE SURE HEATER/DEFROSTER FAN MOTOR IS FUNCTIONALBEFORE USING CAB HEATER PRIOR TO REPAIR. HEATER/DEFROSTER BLOWER SHOULD NOT BEUSED IN "LOW" OR "MEDIUM" SPEEDS WHILE THE VEHICLE IS STOPPED OR ENGINE ISIDLING.

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NHTSA Campaign Number: 81V089000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: November 1st, 1980
Manufactured End Date: June 1st, 1981
Date of Owner Notification: January 25th, 1982

Defect Summary:
HOLES DRILLED IN THE REAR AXLE YOKES TO BALANCE THEM COULD CAUSE A FAILURE OF THE YOKE.

Corrective Summary:
VEHICLES WILL BE INSPECTED AND ALL DEFECTIVE YOKES WILL BE REPLACED WITH YOKES WITHOUT HOLES.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS.SYSTEM: SUSPENSION; REAR AXLE YOKE.CONSEQUENCES OF DEFECT: THE YOKE COULD FAIL WITHOUT WARNING DURING VEHICLEOPERATION, POSSIBLY CAUSING LOSS OF VEHICLE CONTROL AND AN ACCIDENT. ALSO, THEFAILURE COULD CAUSE SHRAPNEL TO BE PROPELLED OUTWARD FROM THE VEHICLE, INJURINGANYONE WITHIN CLOSE PROXIMITY.NOTE: THE FAILURE IS MOST LIKELY TO OCCUR WHEN THE VEHICLE IS FIRST STARTED ORWHILE DRIVING AT MODERATE OR HIGH SPEEDS IN A HEAVY TORQUE CONDITION.