Daimler Trucks North America LLC (DTNA) is recalling certain model year 2007-2016 Freightliner 114SD and M2 Business Class trucks, 2008-2009 Sterling LT8500 trucks and Thomas Built Bus Saf-T-Liner HDX transit buses 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.