The 1983 Mack Mh has 8 NHTSA recall campaigns affecting an estimated 36,334 vehicles. Recall repairs are always free at any authorized dealer. Last updated July 5, 2026.
SEAT TETHER BELTS MAY NOT HAVE BEEN ADJUSTED DURING ASSEMBLY.
DURING AN IMPACT, DRIVER AND/OR RIDER CAN MOVE FORWARDAND POSSIBLY STRIKE THE WINDSHIELD, EVEN WHEN WEARING A SEAT BELT.
ADJUST SEAT TETHER BELT IF NECESSARY.
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…
INSTALL A REINFORCEMENT BRACE IF NO CRACKS ARE FOUND. IN ADDITION, REPLACE STEP IF CRACKS ARE PRESENT.
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…
INSTALL TWO NEW SLEEVES IN THE DUAL DOUBLE CHECK VALVE WHICH WILL INCREASE AIR FLOW.
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…
REMOVE THE STEP CLEVIS AND REPLACE WITH A NEW IMPROVED CLEVIS.
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.
THE DEALER WILL INSPECT AND REMOVE THE FIFTH WHEEL AND REWELD THE MOUNTING ANGLES AT NO CHARGE TO THE OWNER.
A MANUFACTURING ERROR RESULTED IN THE INSTALLATION OF CARBON STEEL SPRINGS IN SOME DUAL-COMPARTMENT AIR RESERVOIR CHECK VALVES. CARBON STEEL SPRINGS ARE INADEQUATE FOR THIS APPLICATION BECAUSE THEY ARE SUBJECT TO SEVERE CORROSION AND SUBSEQUENT FAILURE OF THE CHECK VALVE.
THE CARBON STEEL SPRING WILL BE REPLACED WITH A STAINLESS STEEL ONE.
IMPROPER STEERING CLAMP BOLTS AND TORQUE APPLIED DURING INSTALLATION. THE BOLT COULD FAIL, ALLOWING THE STEERING YOKE TO BECOME LOOSE.
INSPECTION AND, IF NECESSARY, INSTALLATION OF PROPER STEERING SHAFT CLAMP BOLTS TIGHTENED TO SPECIFICATIONS.
UNDER SEVERE STRAIN, A DEFECTIVE WELD JOINING THE STEERING WHEEL HUB TO THE HUB PERIMETER COULD FAIL, CAUSING THE STEERING WHEEL TO SEPARATE FROM THE VEHICLE.
DEFECTIVE STEERING WHEELS WILL BE REPLACED AT NO CHARGE TO OWNER.
Recall, complaint, and investigation records from official NHTSA datasets (FLAT_RCL, FLAT_CMPL, FLAT_INV), synced weekly. Counts reflect NHTSA records for the 1983 Mack Mh as of July 5, 2026. Complaint narratives are consumer-submitted and unverified. This page contains ads and affiliate links. Full methodology.