1974 Mack Rm Recalls

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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: 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: 75V192000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: February 20th, 1976

Recall Notes:
MACK CAMPAIGN NO N/A.TRUCKS WITH DUAL BRAKE TREADLE VALVE PIPING SEPT.1974AND MAR.31, 1975.POSSIBILITY THAT THE PRIMARY AND SECONDARY AIR SUPPLYLINES MAY HAVE BEEN CONNECTED IN REVERSE AT THE DUAL BRAKE TREADLE VALVE.THEREVERSING OF THESE SUPPLY LINES DOES NOT IN ITSELF, AFFECT VEHICLE BRAKING IFBOTH THE PRIMARY AND SECONDARY AIR SUPPLY SYSTEMS HAVE NORMAL OPERATING AIRPRESSURE.HOWEVER, IN THE EVENT OF LOSS OF AIR PRESSURE IN EITHER THE PRIMARYOR SECONDARY SYSTEM, NEITHER THE PRIMARY NOR SECONDARY SERVICE BRAKES WOULDFUNCTION WHEN APPLIED.IN THIS EVENT, IT WOULD REQUIRE MANUAL APPLICATION OFTHE EMERGENCY SPRING BRAKE TO STOP VEHICLE.(CORRECT BY INSPECTING ANDREROUTING AIR SUPPLY PIPING AS REQUIRED TO CORRECT SYSTEM).