The 1974 Mack Dmm has 4 NHTSA recall campaigns affecting an estimated 72,700 vehicles. Recall repairs are always free at any authorized dealer. Last updated July 5, 2026.
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 DEALER WILL INSPECT AND, IF NECESSARY, INSTALL CROSS STEERING ARMS OF IMPROVED DESIGN AND GREATER STRENGTH.
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.
THE DEALER WILL INSPECT AND, IF NECESSARY, REPLACE THE ANTI-WHEEL LOCK CONTROLLER WITHOUT CHARGE 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.
DEALER WILL REPLACE THE ORIGINAL FAN WITH A STEEL FIXED BLADE FAN, FREE OF CHARGE.
MACK CAMPAIGN NO N/A.TRUCKS WITH DUAL BRAKE TREADLE VALVE PIPING SEPT.1974AND MAR.31, 1975.POSSIBILITY THAT THE PRIMARY AND SECONDARY AIR SUPPLYLINES MAY HAVE BEEN CONNECTED IN REVERSE AT THE DUAL BRAKE TREADLE VALVE.THEREVERSING OF THESE SUPPLY LINES DOES NOT IN ITSELF, AFFECT VEHICLE BRAKING IFBOTH THE PRIMARY AND…
Recall, complaint, and investigation records from official NHTSA datasets (FLAT_RCL, FLAT_CMPL, FLAT_INV), synced weekly. Counts reflect NHTSA records for the 1974 Mack Dmm as of July 5, 2026. Complaint narratives are consumer-submitted and unverified. This page contains ads and affiliate links. Full methodology.