1973 Mack R Recalls

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NHTSA Campaign Number: 78V171000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: August 10th, 1979

Defect Summary:
DEFICIENCIES, IN THE FORM OF FORGING LAPS, CRACKS AND EXCESSIVE DECARBURIZATION DURING HEAT TREATMENT, EXIST IN THE STEERING KNUCKLES. STRESSES IMPOSED WITH INTEGRAL HYDRAULIC POWER STEERING MAY LEAD TO A FAILURE IN THE AREA OF THE STEERING ARM ATTACHING BOSS. THIS TYPE OF FAILURE WOULD CAUSE LOSS OF STEERING CONTROL.

Corrective Summary:
DEALER WILL INSPECT AND, IF NECESSARY, REPLACE THE LEFT STEERING KNUCKLE WITH AN IMPROVED TYPE OF KNUCKLE.

Recall Notes:
VEHICLE DESCRIPTION: TRUCK TRACTORS.SYSTEM: STEERING; STEERING KNUCKLE.CONSEQUENCES OF DEFECT: LOSS OF STEERING CONTROL COULD CAUSE A VEHICLEACCIDENT.

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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: 74V001000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: March 15th, 1974

Recall Notes:
MACK CAMPAIGN NO SCO#45.EQUIPPED WITH FA535 FRONT AXLE.TRUCKS.POSSIBILITYTHAT THE AXLE BEAM MAY HAVE SURFACE CRACKS ON THE UNDERSIDE BELOW THE SPRINGPADS.SUCH CRACKS COULD OVER A LONG PERIOD OF TIME PROGRESS TO BEAM FAILUREAND LOSS OF VEHICLE CONTROL.(CORRECT BY INSPECTING AND REPLACING WHERENECESSARY).

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NHTSA Campaign Number: 76V057000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: September 13th, 1976

Recall Notes:
MACK CAMPAIGN NO SC074.TRUCK-TRACTOR EQUIPPED WITH ROCKWELL INTERNATIONALSTEERING ARM.POSSIBILITY THAT THE STEERING ARM MAY CONTAIN A FORGING FLAWWHICH COULD RESULT IN A FAILURE DURING NORMAL OPERATION.FAILURE OF THESTEERING ARM COULD LEAD TO A LOSS OF VEHICLE CONTROL WITHOUT PRIOR WARNING TOTHE DRIVER WITH POSSIBLE VEHICLE CRASH OCCURRENCE.(CORRECT BY INSPECTING ANDREPLACING STEERING ARMS).

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NHTSA Campaign Number: 74V002000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: March 19th, 1974

Recall Notes:
MACK CAMPAIGN NO SCO#46.MODELS EQUIPPED WITH TURBO UNLOADER.MAR 1969 THRUNOV 1973.TRUCKS.POSSIBILITY THAT THE OIL SUPPLY LINE TO THE TURBO UNLOADERIS ROUTED TOO CLOSE TO THE TURBO CHARGER.IF THIS CONDITION EXISTS, HEAT COULDCAUSE HOSE DETERIORATION AND OIL LEAKAGE WHICH COULD CREATE A FIRE HAZARD.(CORRECT BY INSPECTING AND RELOCATING OIL LINES TO PROVIDE ADEQUATE CLEARANCEBETWEEN OIL SUPPLY LINE AND TURBO CHANGER).

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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).

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NHTSA Campaign Number: 75V118000
Manufacturer: Mack Trucks, Inc.
Date of Owner Notification: November 11th, 1975

Recall Notes:
MACK TRUCKS CAMPAIGN NO SC060.TRUCKS MFG'D 1967 THRU JAN.31, 1973.POSSIBILITY THAT THE SUSPENSION TRUNNION BRACKETS MAY DEVELOP CRACKS.IF SUCHCONDITION EXISTS AND CRACKS ARE NOT DETECTED, CONTINUED OPERATION COULDULTIMATELY LEAD TO TRUNNION TUBE SEPARATION FROM THE TRUNNION AND PERMIT AXLEASSEMBLY DISLOCATION.FAILURE OF THE TRUNNION BRACKET COULD RESULT IN LOSS OFVEHICLE CONTROL WITHOUT WARNING TO THE DRIVER.(CORRECT BY INSPECTING ANDREPLACING BRACKETS WHERE NECESSARY).