2012 Mack Mru recalls

Defect: Mack Trucks, Inc. (Mack) is recalling certain 2010-2018 MRU and 2019-2025 Terrapro towing vehicles. The vehicles are missing the anti-lock brake (ABS) warning light and circuitry that controls the anti-lock brake function for an attached trailer. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 121, "Air Brake Systems.".

Why it matters: Driving without a functioning anti-lock brake system may result in the trailer not braking as intended, increasing the risk of a crash.

Dealers will add an ABS warning light and circuitry, free of charge. Owner notification letters were mailed April 28, 2025. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0474.

Owner notification: April 30, 2025 · Filing manufacturer: Mack Trucks, Inc.

Defect: Mack Trucks, Inc. (Mack) is recalling certain model year 2011-2016 Mack MRU and LEU trucks manufactured June 25, 2010, to April 30, 2015, and 2015-2016 LR6 trucks manufactured from December 18, 2014 through March 6, 2015. Excessive engine crankcase pressures may cause the 90-degree elbow of the vent tube assembly to detach from the crankcase ventilation breather, possibly allowing engine oil to come into contact with hot surfaces.

Why it matters: If engine oil comes into contact with a hot surface, there could be an increased risk of a fire.

Cummins will notify owners on behalf of Mack, and Cummins service centers will administer the repairs which include securing the ends of the 90-degree elbow and reprogramming the electronic control module (ECM) with software that can adjust the engine output under misfire conditions to limit crankcase pressures. These repairs will be performed free of charge. The recall began on June 12, 2015. Owners may contact Mack customer service at 1-800-528-6586 or Cummins Inc. at 1-800-343-7357. Mack's number for this recall is SC0391.

Owner notification: June 12, 2015 · Filing manufacturer: Mack Trucks, Inc.

Defect: Mack Trucks Inc. (Mack) is recalling certain model year 2010-2014 CHU, CXU, and MRU, 2007 CT and CV, 2008-2014 GU, and 2011-2014 LEU, and TD trucks manufactured February 28, 2006, through November 8, 2013, and equipped Hamsar Electronic Flasher. The hazard warning lights may fail.

Why it matters: A failure of the hazard warning lights could reduce the trucks visibility, increasing the risk of a crash.

Mack will notify owners, and dealers will replace the electronic flasher unit, free of charge. The recall will begin by mid-June 2014. Interim letters went out to owners on June 23, 2014. The recall began on July 25, 2014. Owners may contact Mack customer service at 1-866-298-6586. Mack's number for this recall is SC0379.

Owner notification: July 25, 2014 · Filing manufacturer: Mack Trucks, Inc.

Defect: Mack Trucks Inc. (Mack) is recalling certain model year 2014-2015 CXU, 2010-2015 LEU, and 2011-2015 MRU vehicles manufactured with certain Cummins Westport Model ISL G and ISX12 G engines. Condensation in the intake manifold may freeze during cold weather conditions and interfere with the proper operation of the intake manifold pressure sensor.

Why it matters: The improper operation of the sensor could induce elevated exhaust temperatures or flames from the exhaust pipe, increasing the risk of a vehicle fire or burn injury to a person near the exhaust pipe.

Cummins and Cummins Westport will notify owners, and authorized Cummins service facilities will upload a new ECM calibration, free of charge. The recall began on March 12, 2014. Customers may contact Mack at 1-336-393-2000 or Cummins Inc. at 1-800-343-7357. Mack's number for this recall is SC0377.

Owner notification: March 12, 2014 · Filing manufacturer: Mack Trucks, Inc.

Defect: Mack is recalling certain model year 2010-2012 leu and model year 2011-2012 mru vehicles, manufactured from may 14, 2009, through october 31, 2011, and built to operate on compressed natural gas. on these vehicles the alternator ground cable runs directly to the starter, which defeats the circuit protection.

Why it matters: In the event of an electrical short, a vehicle fire may result.

Mack will notify owners, and dealers will relocate the alternator ground cable to the engine ground stud. this service will be performed free of charge. the recall began on april 19, 2012. owners may contact mack trucks at 1-800-866-1177.

Owner notification: April 19, 2012 · Filing manufacturer: MACK TRUCKS, INC

Defect: Mack trucks is recalling certain model year 2009-2012 mru heavy trucks manufactured from november 26, 2008, through april 26, 2011. the bolts used to mount the steering gear were not tightened to specification. the bolts can loosen which over time may cause the steering gear to disconnect from its mounting bracket.

Why it matters: A complete loss of steering may occur increasing the risk of a vehicle crash.

Dealers will replace the bolts, which will be tightened to the correct specification. this service will be performed free of charge. the safety recall began on september 19, 2011. owners may contact mack trucks at 1-800-866-1177.

Owner notification: September 19, 2011 · Filing manufacturer: MACK TRUCKS, INC

Defect: Mack trucks is recalling certain model year 2012, chu, cxu, gu, mru, leu, and td trucks equipped with a meritor driveline. the tubing used to assemble the affected drivelines has a nonconforming seam weld with insufficient bonding of the material.

Why it matters: This can result in seam weld fracture when torque is applied. once the tube seam weld is fractured, the driveline may become inoperable which may result in a disabled vehicle or debris from the driveline may fall on the roadway, both of which can increase the risk of a crash.

Dealers will replace the drivelines free of charge. the safety recall began on july 25, 2011. owners may contact mack trucks at 1-800-528-6586.

Owner notification: July 25, 2011 · Filing manufacturer: MACK TRUCKS, INC

Defect: Mack trucks is recalling certain model year 2011-2012 chu, cxu, gu, leu and mru trucks manufactured from october 15, 2010, through january 31, 2011, and equipped with gunite automatic slack adjusters. due to an incomplete "knitting" of the iron at the time of casting, inadequate structural integrity of the slack adjuster housing can occur, which could cause the housing to break at the handle under normal operating loads.

Why it matters: Slack adjusters with this flow notch could crack under normal braking conditions causing loss of braking which could result in a vehicle crash.

Mack trucks will notify owners and dealers will replace the subject slack adjusters free of charge. the safety recall began on august 24, 2011. owners may contact mack trucks at 1-800-528-6586.

Owner notification: August 12, 2011 · Filing manufacturer: MACK TRUCKS, INC

Defect: Mack trucks is recalling certain model year 2008-2012 mru and leu heavy trucks manufactured from january 3, 2007, through february 3, 2011. the electrical circuitry in these vehicles may not provide adequate overcurrent protection.

Why it matters: In the event of an electrical overage, the fuse that should prevent the over current from reaching the mirror switch circuit may fail, such that the mirror switch can overheat. an overheated switch could cause a vehicle fire.

Dealers will install a relay harness to prevent the mirror switch from overheating. they will also inspect the mirror switch and if signs of overheating are shown, replace that switch. all inspections and repairs will be performed free of charge. the safety recall began on june 30, 2011. owners may contact mack trucks at 1-800-866-1177.

Owner notification: June 30, 2011 · Filing manufacturer: MACK TRUCKS, INC