Defect
SEAT TETHER BELTS MAY NOT HAVE BEEN ADJUSTED DURING ASSEMBLY.
Consequence
DURING AN IMPACT, DRIVER AND/OR RIDER CAN MOVE FORWARDAND POSSIBLY STRIKE THE WINDSHIELD, EVEN WHEN WEARING A SEAT BELT.
Remedy
ADJUST SEAT TETHER BELT IF NECESSARY.
1984 Mack MH problems
Verdict · NHTSA data
Limited data — recalls on file
NHTSA has just 0 complaints on file for the 1984 Mack MH — too few to judge reliability from owner reports alone — but 9 recall campaigns apply to this year, so any used example should have its VIN checked for completed recall work.
0
NHTSA complaints
9
Recalls
0
Investigations
0
Crash-involved
0
Fires reported
0
Injuries
0
Deaths
—
NCAP overall
Does the 1984 Mack MH have recalls?
9 NHTSA recall campaigns on file. Recall repairs are free at franchised dealers.
Defect
LEFT OR RIGHT CAB STEP MAY CRACK IN ITS WELDED AREA DUE TO FLEXING OF THE STEP DURING ENTERING AND EXITING. CONSEQUENCE OF DEFECT: AS THE CRACKS EXTEND, THE TUBULAR STEP COULD PARTIALLY COLLAPSE AND BREAK WITHOUT WARNING TO THE USER, AND COULD RESULT IN PERSONAL INJURIES.
Remedy
INSTALL A REINFORCEMENT BRACE IF NO CRACKS ARE FOUND. IN ADDITION, REPLACE STEP IF CRACKS ARE PRESENT.
Defect
THE DUAL DOUBLE CHECK VALVE MAY NOT RELEASE THE PROPER AIR VOLUME TO THE BRAKE SYSTEM, CAUSING A SLIGHT TIMING DELAY BETWEEN THE TRACTOR AND THE TRAILER BRAKE SYSTEM. CONSEQUENCES OF DEFECT: IF THE BRAKES ARE SUDDENLY APPLIED, THE TRAILER COULD JACKKNIFE WITHOUT WARNING TO THE OPERATOR, WHICH COULD RESULT IN A VEHICLE CRASH.
Remedy
INSTALL TWO NEW SLEEVES IN THE DUAL DOUBLE CHECK VALVE WHICH WILL INCREASE AIR FLOW.
Defect
THE DRAG LINKS MAY HAVE BEEN INSTALLED INCORRECTLY ALLOWING DRAG LINK CLAMP BOLT TO AXLE BEAM INTERFERENCE. CONSEQUENCE OF DEFECT: DURING A TURNING MANEUVER, INCREASED STEERING EFFORT OR COMPLETE LOCKUP OF STEERING COULD OCCUR WITHOUT WARNING. THIS COULD RESULT IN LOSS OF TRUCK CONTROL AND A CRASH.
Remedy
ASSURE THAT DRAG LINKS ARE INSTALLED TO CORRECT INTERFERENCE CONDITION.
Defect
THE FLIP OUT STEP CLEVIS ON THE BUMPER MAY FAIL AND BREAK UNDER THE WEIGHT OF THE PERSON STANDING ON THE STEP TO SERVICE THE FRONT AREA OF THE VEHICLE. CONSEQUENCE OF DEFECT: THIS SUDDEN BREAK WILL CAUSE THE PERSON STANDING ON THE STEP TO FALL, WITHOUT WARNING, AND COULD RESULT IN INJURIES.
Remedy
REMOVE THE STEP CLEVIS AND REPLACE WITH A NEW IMPROVED CLEVIS.
Defect
THE SPRING CENTER BOLT IS NOT THE PROPER SIZE OR LENGTH. AS A RESULT, LOCATION AND ALIGNMENT OF THE SPRING TO THE FRONT AXLE MAY NOT BE CORRECT. IF THE FRONT SPRING CLIPS LOOSEN, THE INADEQUATE CENTER BOLT MAY RESULT IN SPRING TO AXLE MISALIGNMENT, SHIFTING OF THE AXLE, AND LOSS OF STEERING CONTROL.
Remedy
THE DEFECT WILL BE CORRECTED BY THE ADDITION OF A SPACER BETWEEN THE SPRING AND THE CENTER BOLT HEAD TO INCREASE THE EFFECTIVE HEAD LENGTH. A LONGER CENTER BOLT WILL ALSO BE INSTALLED FOR POSITIVE RETENTION.
Defect
THE DOOR LATCHES MAY BE DEFECTIVE BECAUSE A PAWL SPRING WAS NOT MANUFACTURED TO SPECIFICATIONS. THE PAWL SPRING DOES NOT CREATE PROPER TENSION ON THE PAWL, (A PART OF THE DOOR LATCH MECHANISM). THIS CONSTITUTES A NON-COMPLIANCE WITH THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 206, "DOOR LATCHES AND DOOR RETENTION COMPONENTS".
Remedy
THE DEALER WILL INSPECT AND REPLACE DOOR LATCHES, IF NECESSARY.
Defect
DUE TO IMPROPER AND INADEQUATE WELDING PRACTICES, THE FIFTH WHEEL ON THE INVOLVED VEHICLES IS DEFECTIVE. FRAME MOUNTED SUPPORTS MAY HAVE INCOMPLETE OR POOR QUALITY WELDS. THE WELDS COULD SUBSEQUENTLY FAIL ALLOWING SEPARATION OF THE TRACTOR FROM THE TRAILER.
Remedy
THE DEALER WILL INSPECT AND REMOVE THE FIFTH WHEEL AND REWELD THE MOUNTING ANGLES AT NO CHARGE TO THE OWNER.
Defect
IMPROPER STEERING CLAMP BOLTS AND TORQUE APPLIED DURING INSTALLATION. THE BOLT COULD FAIL, ALLOWING THE STEERING YOKE TO BECOME LOOSE.
Remedy
INSPECTION AND, IF NECESSARY, INSTALLATION OF PROPER STEERING SHAFT CLAMP BOLTS TIGHTENED TO SPECIFICATIONS.
1984 Mack MH — common questions
Is the 1984 Mack MH reliable?
The record is thin — 0 NHTSA complaints — so owner-report data can't strongly confirm reliability either way, though 9 recalls should be verified as completed.
Does the 1984 Mack MH have recalls?
Yes — NHTSA lists 9 recall campaigns affecting the 1984 Mack MH. Recall repairs are free at franchised dealers; check the VIN at nhtsa.gov/recalls to confirm the work was done.
Related
Based on NHTSA ODI data through June 2026. Complaints are consumer-reported and unverified. Updated July 5, 2026.
Compiled by Sharon Ben-Moshe, Founder.