1978 Mack Rm 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: 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.