1979 Mack Ws Recalls

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NHTSA Campaign Number: 79V133000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: February 1st, 1977
Manufactured End Date: March 1st, 1979
Date of Owner Notification: November 2nd, 1979

Defect Summary:
IN THE EVENT OF TURBOCHARGER COMPRESSOR WHEEL FAILURE, ONE OR MORE OF THE FOUR CAPSCREWS THAT HOLD THE TURBOCHARGER TOGETHER MAY BE STRUCK BY PARTS OF THE COMPRESSOR WHEEL, RESULTING IN THE CAPSCREWS BEING DAMAGED. IF THESE CAPSCREWS ARE DAMAGED TO THE POINT THAT THEY ALLOW THE COMPRESSOR BACK PLATE TO DISLOCATE FROM THE TURBOCHARGER BEARING HOUSING, ENGINE LUBRICATING OIL MAY BE ALLOWED TO ESCAPE UNDER PRESSURE, CONTACTING THE ENGINE EXHAUST MANIFOLD SECTIONS OR TURBOCHARGER TURBINE HOUSING.

Corrective Summary:
DEALER WILL INSTALL A SHIELD FOR THE HEADS OF THE FOUR CAPSCREWS, ALONG WITH STRONGER SAE 8 GRADE 8 CAPSCREWS, IF NECESSARY, AT NO COST TO OWNER.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS EQUIPPED WITH ENDT (B) 676, ETAZ (B) 673A, AND ETAY(B) 673A ENGINES.SYSTEM: ENGINE AND ENGINE COOLING.CONSEQUENCES OF DEFECT: ENGINE LUBRICATING OIL, IN THE PRESENCE OF A SOURCE OFIGNITION, COULD LEAD TO AN ENGINE COMPARTMENT FIRE AND SERIOUS INJURY TOVEHICLE PASSENGERS.

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NHTSA Campaign Number: 79V137000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: May 1st, 1977
Manufactured End Date: April 1st, 1979
Date of Owner Notification: October 22nd, 1979

Defect Summary:
THE PITMAN ARM RETAINING NUT MAY NOT HAVE BEEN TORQUED TO MANUFACTURER SPECIFICATIONS. THIS COULD RESULT IN INADEQUATE RETENTION OF THE NUT AT THE OUTPUT SHAFT, ALLOWING THE PITMAN ARM TO BECOME LOOSE.

Corrective Summary:
DEALER WILL INSPECT AND RETORQUE PITMAN ARM, IF NECESSARY, AT NO COST TO OWNER.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS.SYSTEM: STEERING LINKAGES; ARM, PITMAN.CONSEQUENCES OF DEFECT: THIS CONDITION COULD LEAD TO PREMATURE WEARING OF THEOUTPUT SHAFT CAUSING LOSS OF VEHICLE CONTROL AND AN ACCIDENT.

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NHTSA Campaign Number: 79V171000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: December 10th, 1979

Defect Summary:
THE SPRING SEAT PLATE, LOCATED BETWEEN THE AXLE HOUSING AND THE SUSPENSION SPRINGS, MAY DEFORM DUE TO SPRING BENDING. AS A RESULT, THE CLAMPING FORCE IN THE ASSEMBLY MAY BE REDUCED. LOSS OF CLAMPING FORCE COULD CAUSE SPRING FAILURE AND THE AXLE WILL DISLOCATE. ALSO, THE TIRE COULD COME INTO CONTACT WITH THE SPRING.

Corrective Summary:
THE DEALER WILL REPLACE THE EXISTING SPRING SEAT WITH A NEWLY FABRICATED SEAT WHICH IS WELDED TO THE HOUSING. AN IMPROVED SPRING CLAMPING PLATE AND NEW SPRINGS WILL ALSO BE INSTALLED WITHOUT CHARGE.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS.SYSTEM: SUSPENSION; REAR AXLE ASSEMBLY.CONSEQUENCES OF DEFECT: LOSS OF VEHICLE CONTROL AND AN ACCIDENT COULD RESULTDUE TO DISLOCATION OF AXLE AND TIRE TO SPRING INTERFERENCE.

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NHTSA Campaign Number: 79V164000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: November 1st, 1978
Manufactured End Date: June 1st, 1979
Date of Owner Notification: January 11th, 1980

Defect Summary:
THE FLANGE HEAD PINCH BOLTS USED IN THE YOKES OF THE STEERING SHAFT ASSEMBLIES MAY HAVE BEEN OVERSTRESSED DUE TO THE BOLTS NOT BEING TIGHTENED TO SPECIFICATIONS. AS A RESULT, THE PINCH BOLTS COULD BREAK WHILE IN SERVICE.

Corrective Summary:
FLANGE HEAD PINCH BOLTS WILL BE REPLACED WITH STANDARD GRADE 8 FASTENERS WITHOUT CHARGE TO OWNER.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS.SYSTEM: STEERING; FLANGE HEAD PINCH BOLTS.CONSEQUENCES OF DEFECT: IF BREAKAGE OCCURS, LOSS OF STEERING CONTROL AND AVEHICLE ACCIDENT COULD OCCUR.