1975 Mack Rl Recalls

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NHTSA Campaign Number: 79V134000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: June 1st, 1974
Manufactured End Date: March 1st, 1978
Date of Owner Notification: November 10th, 1979

Defect Summary:
IN THE INVOLVED TRUCKS IT IS POSSIBLE THE ADJUSTABLE STEERING COLUMN REAR MOUNTING BRACKET COULD FAIL, ALLOWING STEERING WHEEL ASSEMBLY TO FALL DOWN ONTO THE OPERATOR"S LAP.

Corrective Summary:
DEALER WILL INSTALL AN ADDITIONAL BRACKET IN THIS AREA TO PREVENT THE STEERING WHEEL FROM DISLOCATING IN THE EVENT OF A BRACKET FAILURE.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS.SYSTEM: STEERING ASSEMBLY; STEERING WHEEL AND COLUMN.CONSEQUENCES OF DEFECT: WHILE STEERING WOULD REMAIN FUNCTIONAL IN THISCONDITION, THE ELEMENT OF SURPRISE TO OPERATOR COULD CAUSE LOSS OF VEHICLECONTROL AND AN ACCIDENT.

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NHTSA Campaign Number: 78V068000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: October 1st, 1974
Manufactured End Date: March 1st, 1976
Date of Owner Notification: September 1st, 1978

Defect Summary:
AN AXLE "NO BRAKE" CONDITION COULD RESULT FROM AN EATON CONTROLLER INTERNAL ELECTRICAL MALFUNCTION. THIS CONDITION MAY CAUSE THE ANTI-WHEEL LOCK VALVE SOLENOID TO BE CONTINUOUSLY ENERGIZED AND PREVENT THE BRAKES FROM BEING APPLIED ON ONE OF THE AXLES. AS A RESULT, THE ANTI-WHEEL LOCK WARNING LAMP IS NOT ACTIVATED.

Corrective Summary:
THE DEALER WILL INSPECT AND, IF NECESSARY, REPLACE THE ANTI-WHEEL LOCK CONTROLLER WITHOUT CHARGE TO OWNER.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS EQUIPPED WITH EATON 21 ANTI-LOCK CONTROLLERS.SYSTEM: SERVICE BRAKES; ANTI-WHEEL LOCK SOLENOID.CONSEQUENCES OF DEFECT: LOSS OF BRAKES ON ANY ONE AXLE WILL RESULT IN EXTENDEDVEHICLE STOPPING DISTANCES, WHICH COULD LEAD TO A VEHICLE ACCIDENT.

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NHTSA Campaign Number: 78V030000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: December 1st, 1975
Manufactured End Date: January 1st, 1978
Date of Owner Notification: August 23rd, 1978

Defect Summary:
A DESIGN DEFICIENCY EXISTS IN THE AIR DRYER PIPING IN THE AREA OF THE PRESSURE RELIEF VALVE AND COMPRESSOR GOVERNOR CONTROL LINK. MOISTURE IS PASSED AND BUILDS UP IN THIS RELIEF VALVE AND CONTROL LINE. IN FREEZING AMBIENT TEMPERATURES, THIS MOISTURE MAY FREEZE, ALLOWING THE CHASSIS AIR SYSTEM PRESSURE TO EXCEED 150 PSI. EXCESSIVE AIR SYSTEM PRESSURE CAN CAUSE SEPARATION OF AIR PIPING CONNECTIONS AND AIR SYSTEM VALVE FAILURE.

Corrective Summary:
THE DEALER WILL RELOCATE THE AIR SYSTEM COMPRESSOR GOVERNOR LINE AND PRESSURE RELIEF VALVE TO ELIMINATE MOISTURE ACCUMULATION.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS EQUIPPED WITH ANCHORLOK AIR DRYERS.SYSTEM: SERVICE BRAKES; AIR SYSTEM AND GOVERNOR CONTROL LINE (AIR DRYER).CONSEQUENCES OF DEFECT: WHEN THIS OCCURS, AUTOMATIC APPLICATION OF THE CHASSISEMERGENCY SPRING BRAKES AND TRAILER BRAKES COULD CAUSE LOSS OF VEHICLE CONTROLWITHOUT PRIOR WARNING AND A VEHICLE ACCIDENT.NOTE: OWNER/DRIVER IS ADVISED NOT TO OPERATE VEHICLE IF AIR PRESSURE EXCEEDS15O PSI.

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NHTSA Campaign Number: 77V173000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: March 23rd, 1978

Defect Summary:
THE FLEX BLADE FANS ON THE INVOLVED VEHICLES MAY DEVELOP CRACKS IN THE LAMINATED STIFFENER AS A RESULT OF FATIGUE DURING OPERATION. IF SUCH A CONDITION EXISTS AND THE CRACKS GO UNDETECTED, CONTINUED OPERATION COULD CAUSE PIECES OF THE STIFFENER TO BREAK OFF.

Corrective Summary:
DEALER WILL REPLACE THE ORIGINAL FAN WITH A STEEL FIXED BLADE FAN, FREE OF CHARGE.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS EQUIPPED WITH SIX-CYLINDER ENGINES.SYSTEM: ENGINE COOLING; FAN.CONSEQUENCES OF DEFECT: BROKEN PIECES CAN BE PROPELLED OUTSIDE OF THE FANSHROUD AND WILL PRESENT AN IMMEDIATE DANGER AND POSSIBLE INJURY TO PERSONSSTANDING NEARBY.NOTE: PRIOR TO CORRECTION, VEHICLE SHOULD NOT BE SERVICED WITH THE HOOD RAISEDAND THE ENGINE RUNNING.

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NHTSA Campaign Number: 76V006000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: May 13th, 1976

Recall Notes:
MACK CAMPAIGN NO SC072.TRUCKS EQUIPPED WITH EATON SKID CONTROL SYSTEM ANDROCKWELL INTERNATIONAL FF931 OR FL931 W FRONT AXLES WITH ALUMINUM WHEEL HUBS.POSSIBILITY THAT FULL ADJUSTMENT OF THE WHEEL SPEED SENSOR CANNOT BE OBTAINEDWITH THE PRESENT EATON WHEEL SPEED ROTOR.IF THIS RESULTS IN INTERFERENCEBETWEEN THE ROTOR AND SENSOR ON ONLY ONE WHEEL OF THE FRONT AXLE AND THEINTERFERENCEIS SUFFICIENT TO DAMAGE THE SENSOR, THEN ANTI-WHEEL LOCK CAPABILITYWILL BE LOST ON THE FRONT AXLE AND THE ANTI-WHEEL LOCK WARNING LIGHT INDICATORWILL ACTIVATE, ALERTING THE DRIVER.HOWEVER, IN THE EVENT SENSOR-TO-ROTORINTERFERENCE ON BOTH WHEELS OF THE FRONT AXLE, AND CAUSES DAMAGE TO BOTHSENSOR, THE ANTI-WHEEL LOCK CAPABILITY WILL BE LOST ON THE FRONT AXLE, BUT THEANTI-WHEEL LOCK INDICATOR WARNING LIGHT WILL NOT BE ACTIVATED.ABSENCE OF THEANTI-LOCK CAPABILITY COULD RESULT IN IMPAIRED VEHICLE CONTROL SHOULD THE DRIVERUNDERTAKE A PANIC STOP IN SLIPPERY ROAD CONDITIONS.(CORRECT BY INSPECTING ANDREPLACING EATON WHEEL ROTORS WITH IMPROVED PARTS AND REPLACE DAMAGED SENSOS).

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NHTSA Campaign Number: 75V070000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: September 23rd, 1975

Recall Notes:
MACK CAMPAIGN NO K1006.TRUCKS WITH PERLUX LAMPS MFG'D NOV.15, 1973 THRUJAN.2, 1975.POSSIBILITY THAT PERLUX ROAD LAMPS CIRCUIT WAS WIRED PARALLELWITH THE HEADLAMPS.THIS RESULTED IN AN ELECTRICAL OVERLOAD AND CAUSED THECIRCUIT BREAKER TO CYCLE OR "TRIP", CAUSING MOMENTARY LOSS OF FORWARDILLUMINATION.(CORRECT BY INSPECTING AND PROVIDING SEPARATE CIRCUIT BREAKER TOPREVENT OVERLOAD).

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NHTSA Campaign Number: 75V139000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: November 14th, 1975

Recall Notes:
MACK CAMPAIGN NO SCO-61.TRUCKS.POSSIBILITY THAT THE REINFORCEMENT INSERTSPECIFIED IN CONNECTOR USED WITH SYNFLEX HOSE MAY HAVE BEEN OMITTED.THISCONDITION COULD RESULT IN INADEQUATE RETENTION OF THE HOSE TO THE CONNECTOR ANDCOULD ALLOW HOSE TO DISCONNECT DURING BRAKE APPLICATION, CAUSING LOSS OFBRAKING ON THE AFFECTED WHEEL.(CORRECT BY INSPECTING AND INSTALLING PROPERASSEMBLY WHERE NECESSARY).

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NHTSA Campaign Number: 75V141000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: November 17th, 1975

Recall Notes:
MACK CAMPAIGN NO SCO-63.TRUCKS MFG'D DEC.12, 1974 THRU JUNE 30, 1975.POSSIBILITY THAT THE TRAILER SUPPLY CONTROL VALVE EXHAUST PORT WAS INADVERTENLYPLUGGED, AND THE SAFETY VALVE ON THE AIR RESERVOIR MAY HAVE BEEN OMITTED.IFTHIS CONDITION EXISTS IT COULD LEAD TO INTERMITTENT LOCKUP OF THE TRAILERBRAKES AND DIFFICULTY IN CHARGING THE TRAILER BRAKE AIR SYSTEM.(CORRECT BYINSPECTING AND INSTALLING VALVE AND UNPLUG CONTROL VALVE).