WASHINGTON, D.C. --- Paccar Inc. is recalling 178 MY 2008-2010 Kenworth trucks and MY 2009-2010 Peterbilt trucks built on a Cummins diesel engine. 

According to NHTSA, the vehicles may be designed with a hard-wired, dash-mounted switch that enables drivers to inhibit after-treatment diesel particulate filter regeneration in environments where the driver believes elevated exhaust temperatures pose a safety hazard. Because of an issue with the logic in the ECM software in these engines, the switch may malfunction.

As a result, the operator may believe the switch is in "inhibit" mode when it actually is not. This condition might permit hot exhaust gases to exit the truck tailpipe, increasing the risk of fire or of melting or burning of nearby surfaces. 

Paccar is working with Cummins to repair the engines free of charge. The safety recall began this month.