1981 Mack Ms300t Recalls

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NHTSA Campaign Number: 83V102000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: November 1st, 1980
Manufactured End Date: July 1st, 1981
Date of Owner Notification: January 3rd, 1984

Defect Summary:
THE YOKE OF THE TRANSMISSION PROPELLER SHAFT MAY LACK REQUIRED STRENGTH DUE TO ERRONEOUS COUNTERBORE OPERATION IN WHICH 10 MILLIMETERS OF EXTRA MATERIAL MAY HAVE BEEN CUT. THIS CONDITION COULD LEAD TO FRACTURE OF THE YOKE IN SERVICE.

Corrective Summary:
ALL AFFECTED PARTS WILL BE INSPECTED AND REPLACED, IF NECESSARY.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS.SYSTEM: POWER TRAIN; TRANSMISSION PROPELLER SHAFT YOKE.CONSEQUENCES OF DEFECT: DURING ENGINE OPERATION AT HEAVY THROTTLE, AS INVEHCILE STARTING, FRAGMENTS OF A FRACTURED YOKE COULD BE PROPELLED OUTWARD ANDCAUSE INJURY TO NEARBY PERSONS.NOTE: THE FRACTURE COULD ALSO OCCUR WITHOUT WARNING DURING NORMAL HIGHWAYOPERATION, RESULTING IN LOSS OF POWER AT THE DRIVING WHEELS, DIFFICULTY INMAINTAINING VEHICLE CONTROL, AND A POSSIBLE ACCIDENT.

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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: 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.

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NHTSA Campaign Number: 81V032000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: November 1st, 1980
Manufactured End Date: February 1st, 1981

Defect Summary:
ON CERTAIN VEHICLES, THE SEMI-TRAILER STOP LIGHTS MAY NOT ACTIVATE WHEN HAND CONTROL LEVER IS ACTIVATED.

Corrective Summary:
AFTER INSPECTING BRAKE LIGHT SYSTEM, A SWITCH WILL BE INSTALLED WHICH WILL ACTIVATE THE TRAILER STOP LIGHT WHEN THE HAND CONTROL VALVE IS USED, IF NECESSARY.

Recall Notes:
VEHICLE DESCRIPTION: HEAVY TRUCKS.SYSTEM: LIGHTING; REAR BRAKE LIGHTS, TRAILER STOP LAMP WIRING.CONSEQUENCES OF DEFECT: REAR-END COLLISION COULD RESULT DUE TO FAILURE OFTRAILER STOP LAMPS. OPERATER OF VEHICLE TO THE REAR WOULD NOT BE WARNED OFBRAKING ACTION ON AFFECTED VEHICLES.