The 1981 Mack Ms300t has 4 NHTSA recall campaigns affecting an estimated 6,915 vehicles. Recall repairs are always free at any authorized dealer. Last updated July 5, 2026.
THE YOKE OF THE TRANSMISSION PROPELLER SHAFT MAY LACK REQUIRED STRENGTH DUE TO ERRONEOUS COUNTERBORE OPERATION IN WHICH 10 MILLIMETERS OF EXTRA MATERIAL MAY HAVE BEEN CUT. THIS CONDITION COULD LEAD TO FRACTURE OF THE YOKE IN SERVICE.
ALL AFFECTED PARTS WILL BE INSPECTED AND REPLACED, IF NECESSARY.
THE CIRCUIT WIRING ON THESE VEHICLES IS ARRANGED SO THAT A SHORT CIRCUIT IN THE REAR TAILLIGHTS WILL ALSO RESULT IN LOSS OF POWER TO THE HEADLAMPS. FOR SAFETY REASONS THE LIGHTING SYSTEM WIRING SHOULD BE INDEPENDENT.
VEHICLES WILL HAVE AN AUTOMATIC RESET CIRCUIT BREAKER INSTALLED TO ENSURE CONTINUED HEADLAMP ILLUMINATION IN THE EVENT OF A SHORT IN OTHER LIGHTING SYSTEMS.
HOLES DRILLED IN THE REAR AXLE YOKES TO BALANCE THEM COULD CAUSE A FAILURE OF THE YOKE.
VEHICLES WILL BE INSPECTED AND ALL DEFECTIVE YOKES WILL BE REPLACED WITH YOKES WITHOUT HOLES.
ON CERTAIN VEHICLES, THE SEMI-TRAILER STOP LIGHTS MAY NOT ACTIVATE WHEN HAND CONTROL LEVER IS ACTIVATED.
AFTER INSPECTING BRAKE LIGHT SYSTEM, A SWITCH WILL BE INSTALLED WHICH WILL ACTIVATE THE TRAILER STOP LIGHT WHEN THE HAND CONTROL VALVE IS USED, IF NECESSARY.
Recall, complaint, and investigation records from official NHTSA datasets (FLAT_RCL, FLAT_CMPL, FLAT_INV), synced weekly. Counts reflect NHTSA records for the 1981 Mack Ms300t as of July 5, 2026. Complaint narratives are consumer-submitted and unverified. This page contains ads and affiliate links. Full methodology.