1974 Mack Fl Recalls

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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: 75V060000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: August 5th, 1975

Recall Notes:
MACK CAMPAIGN NO N/A.TRUCKS MFG'D APRIL 1, 1974 THRU NOV.15, 1974.POSSIBILITY THAT ON MODELS WITH OUTBOARD-MOUNTED BRAKE DRUMS AND STEEL DISCWHEEL ON ALUMINUM WHEEL HUBS, THE MANUFACTURING TOLERANCES MAY CAUSE ANINTERFERENCE PROBLEM BETWEEN THE INSIDE PORTION OF WHEEL AND OUTER EDGE OF CASTDRUM.THIS CONDITION RESULTS IN OVERSTRESS OF WHEEL STUDS.THE FAILURE OFWHEEL STUDS COULD CAUSE SEPARATION OF DISC WHEEL FROM CHASSIS AND COULD CAUSELOSS OF VEHICLE CONTROL.(CORRECT BY INSPECTING AND ADJUSTING TO PRECLUDEINTERFERENCE WHERE NECESSARY).

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NHTSA Campaign Number: 73V205000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: June 1st, 1973
Manufactured End Date: September 1st, 1973
Date of Owner Notification: November 6th, 1973

Recall Notes:
MACK CAMPAIGN NO SCO44.WITH RIM ASSEMBLY 14QJ19305.TRUCKS.POSSIBILITYTHAT THE INCORRECT BASE RIMS OR SIDE RINGS OF THE WHEEL ASSEMBLY MAY HAVE BEENINSTALLED.THE OPERATION OF VEHICLES WITH INCORRECT SIDE RING OR BASE RIMCOULD LEAD TO LOSS OF VEHICLE CONTROL.RIM SEPARATION COULD OCCUR WHEN VEHICLEIS NOT IN OPERATION AND CAUSE SERIOUS PERSONAL INJURY TO ANYONE IN THEIMMEDIATE VICINITY.(CORRECT BY INSPECTION AND REPLACING INCORRECT BASE RIMSOR SIDE RINGS).

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NHTSA Campaign Number: 75V070000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: September 23rd, 1975

Recall Notes:
MACK CAMPAIGN NO K1006.TRUCKS WITH PERLUX LAMPS MFG'D NOV.15, 1973 THRUJAN.2, 1975.POSSIBILITY THAT PERLUX ROAD LAMPS CIRCUIT WAS WIRED PARALLELWITH THE HEADLAMPS.THIS RESULTED IN AN ELECTRICAL OVERLOAD AND CAUSED THECIRCUIT BREAKER TO CYCLE OR "TRIP", CAUSING MOMENTARY LOSS OF FORWARDILLUMINATION.(CORRECT BY INSPECTING AND PROVIDING SEPARATE CIRCUIT BREAKER TOPREVENT OVERLOAD).

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NHTSA Campaign Number: 74V228000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: April 14th, 1975

Recall Notes:
MACK CAMPAIGN NO 56.MODEL WITH SWS56, SWS57, SWS76 SERIES BOGIES, ALUMINUMHUBS AND DISC REAR WHEELS.BUILT 7/15 74 THRU 11/14 74.POSSIBILITY THATINCORRECT STUDS WERE USED TO ATTACH DISC REAR WHEELS TO ALUMINUM HUBS.IF THISOCCURS, THE STUDS WILL LOOSEN AND RESULT IN FAILURE OF THE HUB,DRUM OR WHEELAND COULD LEAD TO SEPARATION OF THE REAR DISC WHEEL FROM THE CHASSIS.(CORRECTBY INSPECTING AND INSTALLING PROPER STUDS WHERE NECESSARY).