1977 Mack Rs 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: 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: 78V210000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: October 1st, 1977
Manufactured End Date: September 1st, 1978
Date of Owner Notification: November 7th, 1978

Defect Summary:
DELAYS OF UP TO ABOUT 2 SECONDS MAY EXIST IN THE BRAKE APPLICATION TIMES TO THE BRAKES ON THE BOGIE AXLES IN THE PRESENCE OF CERTAIN TYPES OF WHEEL SPEED SENSOR SIGNAL DISCONTINUITIES OR DISTORTIONS THAT MAY OCCUR AS A RESULT OF SENSOR WIRE FAILURE. THIS CONSTITUTES A NON-COMPLIANCE TO FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 121, "AIR BRAKE SYSTEMS".

Corrective Summary:
DEALER WILL INSTALL NEW WHEEL SPEED SENSORS THAT INCORPORATE IMPROVED WIRING AND THE PRESENT BOGIE ANTI-WHEEL LOCK SYSTEM WILL BE CHANGED TO AN AXLE-TO-AXLE SYSTEM FOR IMPROVED RELIABILITY.

Recall Notes:
VEHICLE DESCRIPTION: HEAVY TRUCKS.SYSTEM: SERVICE BRAKES; ELECTRICAL WIRING AND CONNECTORS.CONSEQUENCES OF DEFECT: THIS DELAY IN EFFECTIVE BRAKING ACTION COULD LEAD TO ANACCIDENT UNDER CERTAIN TRAFFIC CONDITIONS.

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NHTSA Campaign Number: 77V149000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: January 17th, 1978

Defect Summary:
THE FRONT WHEEL ALUMINUM HUBS ON THE INVOLVED VEHICLES MAY BE SUBJECT TO CRACKS WHICH MAY PROGRESS CIRCUMFERENTIALLY AROUND THE BARREL OF THE HUB. THIS COULD LEAD TO A FRACTURE IN THE "BARREL" POSITION OF THE HUB AND COMPLETE HUB FAILURE.

Corrective Summary:
DEALER WILL INSTALL STEEL HUBS IN PLACE OF ALUMINUM HUBS WITHOUT CHARGE TO OWNER.

Recall Notes:
VEHICLE DESCRIPTION: TRUCKS EQUIPPED WITH FF-931 FRONT AXLES.SYSTEM: WHEELS; ALUMINUM HUBS, FRONT.CONSEQUENCES OF DEFECT: HUB FAILURE COULD RESULT IN LOSS OF VEHICLE CONTROL ANDAN ACCIDENT.NOTE: HUB FAILURE MAY BE INDICATED BY AN AUDIBLE SOUND AT THE INSTANT OF HUBSEPARATION, ALONG WITH THUMPING OR WHEEL WOBBLE. HUB MAY SEPARATE FROM THEWHEEL AND STILL BE RETAINED ON THE AXLE.

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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: 77V205000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: May 1st, 1977
Manufactured End Date: October 1st, 1977
Date of Owner Notification: March 14th, 1978

Defect Summary:
A DEFICIENCY EXISTS IN THE WELDS SECURING THE REAR SPRING INSULATOR BRACKET TO THE AXLE HOUSING. THIS IS DUE TO IMPROPER POSITIONING OF THE WELD, IN RELATIONSHIP TO THE BRACKET AND AXLE HOUSING. FAILURE OF THE WELDS WOULD CAUSE SEPARATION OF THE SPRING INSULATOR BRACKET AND THE AXLE HOUSING, RESULTING IN IMPROPER ALIGNMENT OF THE AFFECTED AXLE.

Corrective Summary:
DEALER WILL REWELD THE INSULATOR SPRING BRACKET AT NO COST TO OWNER.

Recall Notes:
VEHICLE DESCRIPTION: HEAVY TRUCKS.SYSTEM: SUSPENSION; TANDEM AXLE.CONSEQUENCES OF DEFECT: THIS CONDITION COULD CAUSE A LOSS OF VEHICLE CONTROLAND A VEHICLE ACCIDENT.

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NHTSA Campaign Number: 78V222000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: July 1st, 1977
Manufactured End Date: September 1st, 1978
Date of Owner Notification: February 7th, 1979

Defect Summary:
A SHORT CIRCUIT COULD OCCUR DUE TO CHAFING OR WIRE DISCONNECTION IN THE BOX.

Corrective Summary:
THE WIRING IN THE SLEEPER BOX WILL BE CORRECTED, FREE OF CHARGE.

Recall Notes:
VEHICLE DESCRIPTION: HEAVY TRUCK TRACTORS EQUIPPED WITH THE ABLE BODY COMPANY"SSLEEPER BOX.CONSEQUENCES OF DEFECT: A SHORT CIRCUIT CREATES A POTENTIAL FIRE HAZARD WHICHCOULD JEOPARDIZE THE SAFETY OF VEHICLE OCCUPANTS.