1977 Mack Hmm
Safety record from NHTSA: recalls, owner complaints, investigations and service bulletins.
Have the VIN?
These records cover every 1977 Mack Hmm. To see whether one car still needs a recall repair, decode its VIN or check it with NHTSA.
Recalls
4 recalls name the 1977 Mack Hmm. Newest first.
The involved vehicles do not conform to federal motor vehicle safety standard nos. 207, "seating systems", and 210, "seat belt assembly anchorages". Vehicles equipped with viking t-bar seats have the seat belt anchorage located under the seat. The tether belt ruptured when subjected to the forces required in the safety test.
Risk and remedy
Remedy
Dealer will relocate the tether belt floor anchorage to correct the problem, without charge to owner.
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.
Risk and remedy
Remedy
Dealer will reweld the insulator spring bracket at no cost to owner.
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.
Risk and remedy
Remedy
Dealer will replace the original fan with a steel fixed blade fan, free of charge.
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…
Risk and remedy
Remedy
Dealer will inspect and, if necessary, replace seat belt assemblies without charge to owner.
Service bulletins
Technical service bulletins and other communications the manufacturer sent dealers about this vehicle. Ask a dealer for the full document by its number.
- 10215315Programming Failure - Chassis With Cummins Engine And An Allison Transmission
- 10215312(Back Office) - Cruise Control Inoperative After Updating Software VECU5 Without ESP Package (UESP).
- 10215289Automated Manual Transmission ( AMT ) I-Shift / mDRIVE - Ribbon Harness Replacement - Speed Sensor Bolts, Possible Fault Codes P1058 - 21 Or MID 130 PID 161 FMI 1
- 10215287US10 Emission Engines - Diagnostic Trouble Code ( DTC ) SPN 1231 FMI 9 Troubleshooting.
- 10213658Emcon (Spark Assist) Engine Aftertreatment System Troubleshooting Check Sheet - US07 Emissions
- 10213652Low Oil Pressure Diagnostic Process For 11 Liter Engines
- 10213644Premium Tech Tool ( PTT ) Training Materials And Support Tools
- 10213642No Start Condition After Over The Air Programing - VECU5 No Start "Safe State"
- 10213641Temperature Sensor Troubleshooting Guide - US10+OBD13 And Newer
- 10213640Electronically Controlled Suspension (ECS) Losing Air Pressure
- 10213639Low Voltage Disconnect (LVD), Function Description
- 10213638DEF Pump Troubleshooting Guide - US10+OBD13 And Newer Emissions
- 10213637DEF Pump Cycling periodically Hours After Key Off
- 10213636Selective Catalytic Reduction (SCR) Muffler Troubleshooting Guide - US10+OBD13 And Newer Emissions
- 10213633USE FOR NEW VEHICLES (US21+OBD22 Emissions) - Intermittent Diagnostic Trouble Codes U02A3, U029D, U029E
- 10213632NOx Sensor Troubleshooting Guide - US10+OBD13 And Newer Emissions
- 10213630Mack Chassis - Vehicles Equipped With An Automated Manual Transmission Model F ( AMT-F, mDrive ), Premium Tech Tool ( PTT ) Gearbox Calibration Failure; Gearbox Calibration Operation Stops And Fails At 33% When Run With Transmission Removed
- 10213625Mack - PTO Pump Speed Calculator
- 10213612(Back Office Only) Mack Chassis - Cruise Control Inoperative After Disabling The Electronic Stability Program (ESP)
- 10213609Mack Chassis - Diesel Exhaust Fluid ( DEF ) System Cleaning/Flush After DEF Pump Failure Or System Contamination
- 10213608Mack Chassis - Bendix Vendor Configuration Program ( VCP ) Software Download Information
- 10213605Mack Chassis - Diagnostic Trouble Codes ( DTC's ) - P020113, P020213, P020313, P020413, P020513, P020613, Cylinders 1 Through 6 Injector A Open Circuit
Every Mack Hmm model year
Bars are owner complaints, dots mark years with recalls. Select a year to open its report.