1977 Mack Mb Recalls

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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: 78V172000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: February 22nd, 1979

Defect Summary:
THE EXISTING CROSS STEERING ARMS MAY HAVE INSUFFICIENT FATIGUE LIFE IN THE NECK AREA. THIS IS NEAR THE BOSS FOR THE CROSS STEERING TUBE BALL JOINT CONNECTION. FAILURE OF EITHER OF THE CROSS STEERING LEVERS COULD LEAD TO LOSS OF STEERING CONTROL OF THE RIGHT FRONT WHEEL.

Corrective Summary:
THE DEALER WILL INSPECT AND, IF NECESSARY, INSTALL CROSS STEERING ARMS OF IMPROVED DESIGN AND GREATER STRENGTH.

Recall Notes:
VEHICLE DESCRIPTION: TRUCK TRACTORS.SYSTEM: STEERING; STEERING ARM.CONSEQUENCES OF DEFECT: LOSS OF STEERING CONTROL COULD LEAD TO LOSS OF VEHICLECONTROL AND AN ACCIDENT.

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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: 77V096000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: September 9th, 1977

Defect Summary:
THE FRONT WHEEL RIM CLAMP STUDS, INSTALLED ON THE INVOLVED VEHICLES, MAY NOT HAVE BEEN MANUFACTURED CORRECTLY, CAUSING A BRITTLE CONDITION IN THE THREAD ROOT AREA. THE STUDS COULD EVENTUALLY CRACK AND BREAK WHEN WHEEL NUTS ARE TIGHTENED TO SPECIFICATIONS.

Corrective Summary:
THE DEALER WILL REPLACE ALL SUSPECT FRONT WHEEL STUDS, WITHOUT CHARGE TO OWNER.

Recall Notes:
VEHICLE DESCRIPTION: HEAVY TRUCKS.SYSTEM: WHEELS; STUDS.CONSEQUENCES OF DEFECT: WHEEL STUD FAILURE COULD CAUSE A LOOSENED TIRE ASSEMBLYAND IMPAIRED VEHICLE CONTROL. FAILURE OF MORE THAN ONE STUD COULD CAUSESEPARATION OF THE TIRE AND RIM ASSEMBLY, CAUSING LOSS OF VEHICLE CONTROL AND ANACCIDENT.NOTE: DRIVER MAY BE ALERTED TO THE CONDITION BY A WOBBLE OR VIBRATION IN THEAFFECTED WHEEL.