Verdict · NHTSA data
Limited data — recalls on file
NHTSA has just 0 complaints on file for the 1975 Mack DM — too few to judge reliability from owner reports alone — but 6 recall campaigns apply to this year, so any used example should have its VIN checked for completed recall work.
0
NHTSA complaints
6
Recalls
0
Investigations
0
Crash-involved
0
Fires reported
0
Injuries
0
Deaths
—
NCAP overall
6 NHTSA recall campaigns on file. Recall repairs are free at franchised dealers.
Defect
IN THE INVOLVED TRUCKS IT IS POSSIBLE THE ADJUSTABLE STEERING COLUMN REAR MOUNTING BRACKET COULD FAIL, ALLOWING STEERING WHEEL ASSEMBLY TO FALL DOWN ONTO THE OPERATOR"S LAP.
Remedy
DEALER WILL INSTALL AN ADDITIONAL BRACKET IN THIS AREA TO PREVENT THE STEERING WHEEL FROM DISLOCATING IN THE EVENT OF A BRACKET FAILURE.
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.
Remedy
THE DEALER WILL INSPECT AND, IF NECESSARY, INSTALL CROSS STEERING ARMS OF IMPROVED DESIGN AND GREATER STRENGTH.
Defect
AN AXLE "NO BRAKE" CONDITION COULD RESULT FROM AN EATON CONTROLLER INTERNAL ELECTRICAL MALFUNCTION. THIS CONDITION MAY CAUSE THE ANTI-WHEEL LOCK VALVE SOLENOID TO BE CONTINUOUSLY ENERGIZED AND PREVENT THE BRAKES FROM BEING APPLIED ON ONE OF THE AXLES. AS A RESULT, THE ANTI-WHEEL LOCK WARNING LAMP IS NOT ACTIVATED.
Remedy
THE DEALER WILL INSPECT AND, IF NECESSARY, REPLACE THE ANTI-WHEEL LOCK CONTROLLER WITHOUT CHARGE TO OWNER.
Defect
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
DEALER WILL REPLACE THE ORIGINAL FAN WITH A STEEL FIXED BLADE FAN, FREE OF CHARGE.
The record is thin — 0 NHTSA complaints — so owner-report data can't strongly confirm reliability either way, though 6 recalls should be verified as completed.
Yes — NHTSA lists 6 recall campaigns affecting the 1975 Mack DM. Recall repairs are free at franchised dealers; check the VIN at nhtsa.gov/recalls to confirm the work was done.
Based on NHTSA ODI data through June 2026. Complaints are consumer-reported and unverified. Updated July 5, 2026.
Compiled by Sharon Ben-Moshe, Founder.