1977 Mack HMM: recalls and complaints
NHTSA lists 4 recall campaigns for the 1977 Mack HMM. The newest campaign is 77V205000. NHTSA received the report on 21 Nov 1977. The NHTSA record gives the component Suspension / Rear / Springs / Leaf Spring Assembly / Hanger/Bracket. NHTSA has no complaint on file for this model year.
The NHTSA recall file shows no do-not-drive advisory and no park-outside advisory on these campaigns.
This page cannot show if a recall applies to one vehicle. The NHTSA VIN lookup shows the unrepaired recalls of one vehicle.
Remedy of the newest campaign, 77V205000, in the NHTSA record
Dealer will reweld the insulator spring bracket at no cost to owner.
Complaint information entered into NHTSA’s Office of Defects Investigation vehicle owner's complaint database is used with other data sources to identify safety issues that warrant investigation and to determine if a safety-related defect trend exists.
NHTSA publishes these words. Source: NHTSA Datasets and APIs, section Complaints, read on . Complaint file through . Recall file through .
Since the last update
No tracked figure of this page changed in a data update. What the log tracks
Recall campaigns
4 campaigns, newest first. 62,002 units in total.
- 77V205000Suspension / Rear / Springs / Leaf Spring Assembly / Hanger/Bracket
- 77V204000Seat Belts / Front / Anchorage
- 77V173000Engine and Engine Cooling / Cooling System / Fan
- 77V174000Seat Belts / Front / Anchorage
77V205000Received . 7,400 units.
Suspension / Rear / Springs / Leaf Spring Assembly / Hanger/Bracket
- Defect, in the NHTSA record
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.
- Remedy, in the NHTSA record
Dealer will reweld the insulator spring bracket at no cost to owner.
Report filed by MACK TRUCKS, INCORPORATED. Owner notification date in the NHTSA record: .
77V204000Received . 11 units.
Seat Belts / Front / Anchorage
- Defect, in the NHTSA record
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.
- Remedy, in the NHTSA record
Dealer will relocate the tether belt floor anchorage to correct the problem, without charge to owner.
Report filed by MACK TRUCKS, INCORPORATED. Owner notification date in the NHTSA record: .
77V173000Received . 48,000 units.
Engine and Engine Cooling / Cooling System / Fan
- Defect, in the NHTSA record
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.
- Remedy, in the NHTSA record
Dealer will replace the original fan with a steel fixed blade fan, free of charge.
Report filed by MACK TRUCKS, INCORPORATED. Owner notification date in the NHTSA record: .
77V174000Received . 6,591 units.
Seat Belts / Front / Anchorage
- Defect, in the NHTSA record
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.
- Remedy, in the NHTSA record
Dealer will inspect and, if necessary, replace seat belt assemblies without charge to owner.
Report filed by MACK TRUCKS, INCORPORATED. Owner notification date in the NHTSA record: .
The campaign number opens the NHTSA record. Each quotation is the text of the NHTSA recall file.
Recall campaign: One recall in the NHTSA recall file, with one campaign number. A campaign can name many makes, models and model years.
Units: The number of vehicles or products that a recall can include. The manufacturer or the firm reports the number to the agency.
Complaints by component
The NHTSA complaint file has no complaint for this model year.
Investigations
The NHTSA investigation file has no investigation that names this model year.
Investigation: A study of a possible safety defect by the NHTSA Office of Defects Investigation. An investigation with no closing date in the NHTSA file is open.
Other model years
The number under each year is the number of recall campaigns.
A year without a link has fewer than 2 campaigns and fewer than 25 complaints. It has no page.
Follow by RSS:Mack recallsVehicle recalls
Official channels
- NHTSA VIN lookupNHTSA shows the unrepaired recalls of one vehicle from its VIN or its license plate.
- NHTSA: report a safety problemThe NHTSA form for a complaint about a vehicle, a tire, a child seat or equipment.
- NHTSA page of the 1977 Mack HMMThe recalls, the complaints and the investigations that NHTSA shows for this model year.
Cite this page
Recall Register. 1977 Mack HMM: recalls and complaints. https://recallregister.com/vehicle/mack/hmm/1977/. Source: NHTSA Office of Defects Investigation, recall, complaint and investigation files. Data through .
Sources
- Source
- NHTSA Office of Defects Investigation
- Licence
- US government work, public domain
- Recall file through
- 29 Sep 2026
- Complaint file through
- 29 Mar 2018
- First complaint in the file
- 1 Jan 1995
- Manufacturer in the recall file
- MACK TRUCKS, INCORPORATED
The NHTSA record is the authority. A complaint count is the number of different complaint numbers for the make, the model and the model year. How the register is made. Report an error.
Questions
- How many units are in the recall campaigns for the 1977 Mack HMM?
- 62,002 units in 4 campaigns. A campaign can name other models and model years, and its units include them.
- How many recall campaigns does the Mack HMM have for all model years?
- NHTSA lists 6 recall campaigns for the Mack HMM, model years 1972 to 1977. 4 of them name the 1977 model year.
- Is an NHTSA investigation of the 1977 Mack HMM open?
- The NHTSA investigation file has no investigation that names this model year.