1973 Mack Rd 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: 73V102000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: January 1st, 1971
Manufactured End Date: March 1st, 1973
Date of Owner Notification: August 24th, 1973

Recall Notes:
EQUIPPED WITH ANCHORLOK SPRING BRAKE CHAMBERS.MANF'D JAN.1971 THRU MARCH1973.TRUCKS.POSSIBILITY THAT THE CLAMP RINGBOLTS ON THE ANCHORLOK SPRINGBRAKE CHAMBER WERE INCORRECTLY POSITIONED AT TIME OF INSTALLATION.IN THISPOSITION THE END OF THE BOLT MAY CONTACT REAR AXLE HOUSING DURING BRAKEACTUATION.DUE TO BRACKET DEFLECTION, THE CLAMP RING OR BOLT MAY FAILPERMITTING THE SPRING BRAKE SECTION TO SEPARATE FROM THE SERVICE CHAMBER.(CORRECT BY INSPECTING AND REPOSITIONING CLAMP AND BOLTS).

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NHTSA Campaign Number: 74V227000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: February 7th, 1975

Recall Notes:
MACK CAMPAIGN NO 55.MFG'D JAN.1, 1973 THRU AUG.14, 1974.POSSIBILITYTHAT VEHICLES EQUIPPED WITH A TRACTOR PROTECTION VALVE AN INTERFERENCE COULDOCCUR BETWEEN THE STOP LAMP SWITCH AND THE HEAD LAMP SWITCH COULD CREATE ASHORT CIRCUIT THAT WOULD INTERRUPT HEAD LAMP OPERATION.(CORRECT BY INSPECTINGAND PROVIDING ADDITIONAL CLEARANCE BETWEEN SWITCHES WHERE NECESSARY).

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NHTSA Campaign Number: 73V153000
Manufacturer: Mack Trucks, Inc.
Manufactured Begin Date: February 1st, 1971
Manufactured End Date: June 1st, 1973
Date of Owner Notification: October 22nd, 1973

Recall Notes:
MACK TRUCKS CAMPAIGN NO N/A.MANUF'D FEB.1971 THRU JUNE 1973.TRUCKS.POSSIBILITY THAT THE ELECTRIC HORN MOUNTING BRACKET COULD CRACK AND FAIL.IFTHIS CONDITION EXISTS THE HORN COULD INTERFERE WITH STEERING SHAFT UNIVERSALJOINT AND CAUSE STEERING LOCKUP IN A LEFT HAND TURN SITUATION.(CORRECT BYINSPECTING AND REPLACING HORN ASSEMBLY WITH IMPROVED TYPE BRACKET).