Model year record

1977 MACK R

10 recall campaigns on file for this model year. No owner complaints on file.

Recalls

Recall campaignNHTSA 79V133000

Engine and engine cooling: engine

Component
Engine and engine cooling: engine
Manufacturer
MACK TRUCKS, INCORPORATED
Vehicles affected
23,000
Reported to NHTSA
1979-05-31
Owners notified
1979-11-02

Defect description

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.

Manufacturer remedy

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 campaignNHTSA 79V082000

Steering: steering wheel/handle bar

Component
Steering: steering wheel/handle bar
Manufacturer
MACK TRUCKS, INCORPORATED
Vehicles affected
12,000
Reported to NHTSA
1979-04-03
Owners notified
1979-08-13

Defect description

AN IMPROPER PINCH BOLT AND NUT MAY HAVE BEEN USED IN THE CLAMPING OF THE STEERING SHAFT TO THE STEERING GEAR INPUT SHAFT. DUE TO CLAMPING FORCE LOADS APPLIED AT THE BOLT, THE NUT COULD YIELD, RESULTING IN LOOSENESS OF THE INPUT SHAFT YOKE. SHOULD THIS CONDITION GO UNNOTICED, SPLINE WEAR COULD CAUSE SHAFT SEPARATION.

Manufacturer remedy

VEHICLES WILL BE INSPECTED AND, IF NECESSARY, THE CORRECT FASTENERS WILL BE INSTALLED AT NO CHARGE TO OWNER.

Recall campaignNHTSA 79V017000

Suspension: multiple axle

Component
Suspension: multiple axle
Manufacturer
MACK TRUCKS, INCORPORATED
Vehicles affected
4,000
Reported to NHTSA
1979-01-12
Owners notified
1979-08-13

Defect description

A CASTING DEFICIENCY EXISTS IN THE LOWER SECTION OF THE CAPS RESULTING IN A REDUCTION IN THE THICKNESS OF THE MATERIAL. FAILURE OF A CAP CAN ALLOW THE END OF THE REAR SPRING TO DETACH FROM THE AXLE HOUSING.

Manufacturer remedy

DEALER WILL INSPECT AND, IF NECESSARY, REPLACE ANY OF THE SPRING INSULATOR CAPS FOUND TO BE DEFECTIVE. THIS WILL BE DONE AT NO COST TO OWNER.

Recall campaignNHTSA 78V210000

Service brakes, air: antilock: interconnecting assembly(wiring)

Component
Service brakes, air: antilock: interconnecting assembly(wiring)
Manufacturer
MACK TRUCKS, INCORPORATED
Vehicles affected
19,370
Reported to NHTSA
1978-10-03
Owners notified
1978-11-07

Defect description

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".

Manufacturer remedy

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 campaignNHTSA 78V032000

Engine and engine cooling: engine: gasoline

Component
Engine and engine cooling: engine: gasoline
Manufacturer
MACK TRUCKS, INCORPORATED
Vehicles affected
459
Reported to NHTSA
1978-02-09
Owners notified
1978-10-26

Defect description

THE SYNFLEX-TYPE OIL PRESSURE SIGNAL LINE MAY HAVE BEEN ROUTED TOO CLOSE TO THE EXHAUST MANIFOLD. EXCESSIVE HEAT MAY CAUSE THE LINE TO RUPTURE, AND OIL LEAKAGE MAY OCCUR.

Manufacturer remedy

THE DEALER WILL REROUTE THE OIL PRESSURE SIGNAL LINE TO ELIMINATE POTENTIAL FIRE HAZARD, WITHOUT CHARGE TO OWNER.

Recall campaignNHTSA 78V031000

Suspension: multiple axle

Component
Suspension: multiple axle
Manufacturer
MACK TRUCKS, INCORPORATED
Vehicles affected
33,000
Reported to NHTSA
1978-02-09
Owners notified
1978-08-16

Defect description

THE TEE BRACKET, WHICH IS MOUNTED ON THE FRONT AXLE OF THE BOGIE, MAY FAIL DUE TO VIBRATION BROUGHT ON BY ROAD SURFACE IRREGULARITIES. BRACKET FAILURE WOULD LEAVE THE TEE BRACKET UNSUPPORTED AND CAUSE BROKEN HOSE CONNECTOR FITTINGS. THIS WOULD RESULT IN AUTOMATIC APPLICATION OF THE SPRING EMERGENCY BRAKES.

Manufacturer remedy

THE DEALER WILL REPLACE THE DEFECTIVE BRACKET WITH A REDESIGNED VERSION.

Recall campaignNHTSA 77V205000

Suspension: rear: springs: leaf spring assembly: hanger/bracket

Component
Suspension: rear: springs: leaf spring assembly: hanger/bracket
Manufacturer
MACK TRUCKS, INCORPORATED
Vehicles affected
7,400
Reported to NHTSA
1977-11-21
Owners notified
1978-03-14

Defect description

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.

Manufacturer remedy

DEALER WILL REWELD THE INSULATOR SPRING BRACKET AT NO COST TO OWNER.

Recall campaignNHTSA 77V174000

Seat belts: front: anchorage

Component
Seat belts: front: anchorage
Manufacturer
MACK TRUCKS, INCORPORATED
Vehicles affected
6,591
Reported to NHTSA
1977-10-12
Owners notified
1978-08-23

Defect description

THE INVOLVED VEHICLES DO NOT CONFORM TO FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 209, "SEATBELT ASSEMBLIES". ALTHOUGH THE SEATBELTS IN QUESTION PERFORMED MARGINALLY WITH RESPECT TO THE 5000 LB. LOAD REQUIREMENT, ADDITIONAL TESTING CONFIRMED THAT THE ANCHOR COULD FAIL, ALLOWING EITHER THE ANCHOR TO SLIP OVER THE HOLD-DOWN NUT OR THE ANCHOR TO SEPARATE INTO TWO PIECES.

Manufacturer remedy

DEALER WILL INSPECT AND, IF NECESSARY, REPLACE SEAT BELT ASSEMBLIES WITHOUT CHARGE TO OWNER.

Recall campaignNHTSA 77V173000

Engine and engine cooling: cooling system: fan

Component
Engine and engine cooling: cooling system: fan
Manufacturer
MACK TRUCKS, INCORPORATED
Vehicles affected
48,000
Reported to NHTSA
1977-10-12
Owners notified
1978-03-23

Defect description

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.

Manufacturer remedy

DEALER WILL REPLACE THE ORIGINAL FAN WITH A STEEL FIXED BLADE FAN, FREE OF CHARGE.

Recall campaignNHTSA 77V096000

Wheels

Component
Wheels
Manufacturer
MACK TRUCKS, INCORPORATED
Vehicles affected
825
Reported to NHTSA
1977-06-17
Owners notified
1977-09-09

Defect description

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.

Manufacturer remedy

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

Owner complaints

A complaint is one person's report to a federal agency. It is not a finding.

No complaints recorded for this model year.

Safety recall repairs are provided free of charge by franchised dealers, regardless of vehicle age or mileage. This page displays aggregated data for the model year. To check recall status for a specific vehicle, search its VIN at nhtsa.gov.