Daimler Trucks North America LLC (DTNA) is recalling certain model year 2008-2015 Thomas Built Buses Saf-T-Liner HDX school buses manufactured May 25, 2008, to December 18, 2014, and equipped with certain Cummins Westport ISL G engines. 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.
If engine oil comes into contact with a hot surface, there is an increased risk of a fire.
Cummins will notify owners on behalf of DTNA, and dealers secure the ends of the 90-degree elbow. In addition, the electronic control module (ECM) will be reprogrammed 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 DTNA customer service at 1-800-745-8000, or Cummins customer service at 1-800-343-7357. DTNA's number for this recall is FL-681.
Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.safercar.gov.