PACCAR IS RECALLING MODEL YEAR 2008-2010 KENWORTH T300, T270, AND T370, MODEL YEAR 2009-2010 T800 AND PETERBILT MODEL YEAR 2008-2010 335, 340, AND 367 VEHICLES BUILT ON CUMMINS’ DIESEL ENGINE. THE VEHICLES MAY BE DESIGNED WITH A HARD WIRED, DASH-MOUNTED SWITCH THAT ENABLES THE VEHICLE OPERATOR TO INHIBIT AFTERTREATMENT DIESEL PARTICULATE FILTER REGENERATION IN ENVIRONMENTS WHERE THE OPERATOR BELIEVES IT MAY BE UNSAFE FOR ELEVATED EXHAUST TEMPERATURES. DUE TO AN ISSUE WITH THE LOGIC IN THE ECM SOFTWARE IN THESE ENGINES, THE SWITCH MAY NOT FUNCTION CORRECTLY, LEADING THE OPERATOR TO BELIEVE THAT THE SWITCH IS IN “INHIBIT” MODE WHEN IT IS NOT.