Kenworth is recalling certain model year 2012 and 2013 T270 and T370 medium duty trucks built with Eaton Ultrashift transmissions between December 7, 2011, and April 6, 2012. The air harness from the treadle valve on the affected vehicles was routed in a manner that can cause the air brake lines to be pinched between the cab and the electronic clutch actuator of the Eaton Ultrashift transmission. Significant movement between the cab and transmission can cause progressive wear and an eventual leak in the air lines.