Mack DMM recalls by model year

Reported: 1977-10-12 (October 12, 1977) · Model years: 1972, 1973, 1974, 1975, 1976, 1977

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.

Reported: 1975-10-31 (October 31, 1975) · Model years: 1974, 1975

Reported: 1978-04-04 (April 4, 1978) · Model years: 1974, 1975, 1976

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.

Reported: 1978-08-08 (August 8, 1978) · Model years: 1974, 1975, 1976, 1977, 1978

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.

Reported: 1976-07-28 (July 28, 1976) · Model years: 1976

Reported: 1977-10-12 (October 12, 1977) · Model years: 1977

THE INVOLVED VEHICLES DO NOT CONFORM TO FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 209, "SEATBELT ASSEMBLIES". ALTHOUGH THE SEATBELTS IN QUESTION PERFORMED MARGINALLY WITH RESPECT TO THE 5000 LB. LOAD REQUIREMENT, ADDITIONAL TESTING CONFIRMED THAT THE ANCHOR COULD FAIL, ALLOWING EITHER THE ANCHOR TO SLIP OVER THE HOLD-DOWN NUT OR THE ANCHOR TO SEPARATE INTO TWO PIECES.

Remedy: DEALER WILL INSPECT AND, IF NECESSARY, REPLACE SEAT BELT ASSEMBLIES WITHOUT CHARGE TO OWNER.

Reported: 1978-10-03 (October 3, 1978) · Model years: 1977, 1978

DELAYS OF UP TO ABOUT 2 SECONDS MAY EXIST IN THE BRAKE APPLICATION TIMES TO THE BRAKES ON THE BOGIE AXLES IN THE PRESENCE OF CERTAIN TYPES OF WHEEL SPEED SENSOR SIGNAL DISCONTINUITIES OR DISTORTIONS THAT MAY OCCUR AS A RESULT OF SENSOR WIRE FAILURE. THIS CONSTITUTES A NON-COMPLIANCE TO FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 121, "AIR BRAKE SYSTEMS".

Remedy: DEALER WILL INSTALL NEW WHEEL SPEED SENSORS THAT INCORPORATE IMPROVED WIRING AND THE PRESENT BOGIE ANTI-WHEEL LOCK SYSTEM WILL BE CHANGED TO AN AXLE-TO-AXLE SYSTEM FOR IMPROVED RELIABILITY.

Reported: 1979-05-31 (May 31, 1979) · Model years: 1977, 1978, 1979

IN THE EVENT OF TURBOCHARGER COMPRESSOR WHEEL FAILURE, ONE OR MORE OF THE FOUR CAPSCREWS THAT HOLD THE TURBOCHARGER TOGETHER MAY BE STRUCK BY PARTS OF THE COMPRESSOR WHEEL, RESULTING IN THE CAPSCREWS BEING DAMAGED. IF THESE CAPSCREWS ARE DAMAGED TO THE POINT THAT THEY ALLOW THE COMPRESSOR BACK PLATE TO DISLOCATE FROM THE TURBOCHARGER BEARING HOUSING, ENGINE LUBRICATING OIL MAY BE ALLOWED TO ESCAPE UNDER PRESSURE, CONTACTING THE ENGINE EXHAUST MANIFOLD SECTIONS OR TURBOCHARGER TURBINE HOUSING.

Remedy: DEALER WILL INSTALL A SHIELD FOR THE HEADS OF THE FOUR CAPSCREWS, ALONG WITH STRONGER SAE 8 GRADE 8 CAPSCREWS, IF NECESSARY, AT NO COST TO OWNER.

Reported: 1990-02-23 (February 23, 1990) · Model years: 1980, 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988

CRACK MAY DEVELOP ON STEERING ARM THAT COULD PROGRESS AND REDUCE THE FATIGUE LIFE OF THE STEERING ARM.

Consequence: STEERING ARM COULD FAIL WITHOUT WARNING RESULTING IN LOSS OF STEERING CONTROL AND POSSIBLY A CRASH.

Remedy: INSTALL A REDESIGNED STEERING ARM.

Reported: 1994-02-15 (February 15, 1994) · Model years: 1987, 1988, 1989, 1990, 1991, 1992

FUEL INJECTION SYSTEM RECONFIGURATION TO COMPLY WITH ENGINE EMISSION STANDARDS CAUSE HIGHER ENGINE VIBRATION LEVELS WHICH LEAD TO EARLY WEAR AND COMPLETE FAILURE OF THE SECONDARY THROTTLE RETURN MECHANISM.

Consequence: IN THE EVENT THE PRIMARY THROTTLE RETURN FAILS, FAILURE OF THE SECONDARY THROTTLE RETURN SYSTEM WOULD NOT PROVIDE PROTECTION AGAINST LOSS OF THROTTLE CONTROL.

Remedy: A NEW PRODUCTION SECONDARY THROTTLE RETURN SYSTEM CONFIGURATION WILL BE INSTALLED.

Reported: 1990-03-16 (March 16, 1990) · Model years: 1989

A TOLERANCE MISMATCH IN THE CRANK ASSEMBLY OF THE BOSCH WINDSHIELD WIPER MOTOR COULD CAUSE INSTANTANEOUS SEPARATION OF THE CRANK FROM THE LINKAGE ASSEMBLY IN THE LEFT HAND CONTROL ARM ASSEMBLY; THIS WOULD MAKE THE SYSTEM INOPERABLE.

Consequence: WIPER FAILURE DURING VEHICLE OPERATION COULD REDUCE DRIVER'S ABILITY TO SEE THE ROAD, AND CREATES A POTENTIAL FOR AN ACCIDENT.

Remedy: REPLACE LEFT HAND CONTROL ARM LINKAGE ASSEMBLY.

Reported: 2001-08-01 (August 1, 2001) · Model years: 2000, 2001

VEHICLE DESCRIPTION: HEAVY DUTY TRUCKS EQUIPPED WITH CERTAIN MERITOR-WABCO BRAKE SYSTEM TWO AND FOUR PORT RELAY VALVES. THE VALVE MAY STICK OPEN WHEN A HIGH-PRESSURE APPLICATION IS RELEASED.

Consequence: WHEN THE VALVE STICKS OPEN, IT CAN RESULT IN A TOTAL LOSS OF AIR FROM EITHER THE SERVICE OR THE PARK BRAKE SYSTEM. THE DRIVER MAY LOSE BRAKING ABILITY UNDER A SERVICE APPLICATION, POSSIBLY RESULTING IN A VEHICLE CRASH.

Remedy: DEALERS WILL REPLACE THESE VALVES. OWNER NOTIFICATION BEGAN NOVEMBER 16, 2001. OWNERS WHO TAKE THEIR VEHICLES TO AN AUTHORIZED DEALER ON AN AGREED UPON SERVICE DATE AND DO NOT RECEIVE THE FREE REMEDY WITHIN A REASONABLE TIME SHOULD CONTACT MACK AT 1-610-709-3011 OR MERITOR WABCO AT 800-535-5560.

Reported: 2001-12-21 (December 21, 2001) · Model years: 2001

VEHICLE DESCRIPTION: TRUCKS EQUIPPED WITH E-TECH ENGINES. A CONDITION EXISTS ON THE AUXILIARY DRIVE SHAFT OF THE E-TECH ENGINE THAT CAUSES THE LOSS OF POWER STEERING ON VEHICLES WHERE THE POWER STEERING PUMP IS MOUNTED OFF THE FRONT OF THE ENGINE.

Consequence: THIS COULD RESULT IN THE LOSS OF POWER STEERING.

Remedy: DEALERS WILL INSPECT THE VEHICLES AND REPLACE THE NUT THAT HOLDS THE GEAR TO THE AUXILIARY DRIVE SHAFT. OWNER NOTIFICATION BEGAN MARCH 22, 2002. OWNERS WHO TAKE THEIR VEHICLES TO AN AUTHORIZED DEALER ON AN AGREED UPON SERVICE DATE AND DO NOT RECEIVE THE FREE REMEDY WITHIN A REASONABLE TIME SHOULD CONTACT MACK AT 1-610-709-3011.

Reported: 2003-07-17 (July 17, 2003) · Model years: 2003

CERTAIN HEAVY DUTY VEHICLES FAIL TO COMPLY WITH THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 121, "AIR BRAKE SYSTEMS." IMPROPER SEATING OF THE CHECK VALVE RETAINER IN THE BRASS FITTING HOUSING HAS OCCURRED. IT IS POSSIBLE FOR THE AIR BRAKE SYSTEM PRESSURE TO PUSH THE CHECK VALVE INTERNAL PARTS INTO THE PRIMARY SYSTEM RESERVOIR AND A VEHICLE OPERATOR WOULD NOT KNOW THAT THIS HAS HAPPENED.

Consequence: IN THIS CONDITION, THE VEHICLE WOULD NOT MEET THE EMERGENCY REQUIREMENTS OF THE STANDARD.

Remedy: DEALERS WILL REPLACE THE CHECK VALVE. OWNER NOTIFICATION BEGAN NOVEMBER 26, 2003. OWNERS SHOULD CONTACT MACK AT 1-610-709-3337.