RoadVitals

1977 Mack Mb

Recalls, owner-reported complaints, investigations and safety data

Owner complaintsComplaints are reports submitted to NHTSA by owners and drivers. NHTSA does not verify most reports before publishing them, and a complaint does not establish that a defect exists. Volume is influenced by how many of a vehicle were sold, how long it has been on the road, and how much attention an issue has received.
0
Safety recallsA safety recall is issued when a manufacturer or NHTSA determines that a vehicle has a safety-related defect or does not comply with a federal motor vehicle safety standard. Recall repairs are free. Whether a specific vehicle is covered depends on its VIN — a recall listed for a model year does not necessarily apply to every vehicle of that year.
4
Latest Oct 3, 1978
InvestigationsNHTSA opens an investigation to examine whether a safety defect may exist. An open investigation is not a determination that a defect exists, and many investigations close without a recall. Investigations can, however, lead to one.
0
Crash or fire reportedComplaints whose submitter recorded that a crash or a fire occurred. These are the reporter's own answers on the NHTSA form, not verified findings.
0

Overview

Our database contains no NHTSA owner-reported complaints for the 1977 Mack Mb. 4 safety recalls have been issued covering this model year; and 22 manufacturer communications are on file.

Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.

Safety recalls

4 campaigns cover this model year

Recalls apply to specific vehicles, not to every vehicle of a model year. Check your VIN with NHTSA or your manufacturer's dealer to confirm whether a recall affects your vehicle.

Check a VIN on NHTSA.gov

SERVICE BRAKES, AIR:ANTILOCK:INTERCONNECTING ASSEMBLY(WIRING)

Oct 3, 1978
19,370 units potentially affected
The defect: 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".
The 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.
MACK TRUCKS, INCORPORATEDView on NHTSA.gov

STEERING:LINKAGES:KNUCKLE:SPINDLE:ARM

Aug 8, 1978
13,800 units potentially affected
The defect: THE EXISTING CROSS STEERING ARMS MAY HAVE INSUFFICIENT FATIGUE LIFE IN THE NECK AREA. THIS IS NEAR THE BOSS FOR THE CROSS STEERING TUBE BALL JOINT CONNECTION. FAILURE OF EITHER OF THE CROSS STEERING LEVERS COULD LEAD TO LOSS OF STEERING CONTROL OF THE RIGHT FRONT WHEEL.
The remedy: THE DEALER WILL INSPECT AND, IF NECESSARY, INSTALL CROSS STEERING ARMS OF IMPROVED DESIGN AND GREATER STRENGTH.
MACK TRUCKS, INCORPORATEDView on NHTSA.gov

SUSPENSION:REAR:SPRINGS:LEAF SPRING ASSEMBLY:HANGER/BRACKET

Nov 21, 1977
7,400 units potentially affected
The defect: 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.
The remedy: DEALER WILL REWELD THE INSULATOR SPRING BRACKET AT NO COST TO OWNER.
MACK TRUCKS, INCORPORATEDView on NHTSA.gov

Recent owner complaints

Reports submitted to NHTSA, shown in the owner's own words

No owner complaints recorded for this model year

Either none have been filed with NHTSA, or this vehicle is too new for reports to have accumulated.

Manufacturer communications

A bulletin sent by a manufacturer to its dealers. Not a recall, and repairs are not necessarily free.

KC-750

ENGINE AND ENGINE COOLING

US10 Emission Engines - Diagnostic Trouble Code ( DTC ) SPN 1231 FMI 9 Troubleshooting.

KC-745

POWER TRAIN

Automated Manual Transmission ( AMT ) I-Shift / mDRIVE - Ribbon Harness Replacement - Speed Sensor Bolts, Possible Fault Codes P1058 - 21 Or MID 130 PID 161 FMI 1

KC-2143

VEHICLE SPEED CONTROL

(Back Office) - Cruise Control Inoperative After Updating Software VECU5 Without ESP Package (UESP).

KC-2112

ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING; POWER TRAIN

Programming Failure - Chassis With Cummins Engine And An Allison Transmission

KC-2158

ENGINE AND ENGINE COOLING

Selective Catalytic Reduction (SCR) Muffler Troubleshooting Guide - US10+OBD13 And Newer Emissions

KC-2165

ENGINE AND ENGINE COOLING

DEF Pump Troubleshooting Guide - US10+OBD13 And Newer Emissions

Manufacturers file copies of the bulletins they send to dealers with NHTSA. These often describe diagnostic or repair procedures for a known condition. They are not recalls: repairs described in a bulletin are usually only free if the vehicle is still under warranty or the manufacturer has extended coverage.

Compare model years

Complaint and recall counts across every year of this model

Mack Mb by model year
YearComplaintsRecallsInvestigationsIssue Index
1979010
1978030
1977Viewing040
1976020
1975040
1974040
1973030
1972040
1971050
1970030
1969020
1968020
1967020
1966010
1965010

Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers. Older model years have had longer for reports to accumulate.