2004 Kenworth T300 7.2L 6 Cyl DIESEL. 2005 Kenworth T300 7.2L 6 Cyl DIESEL. 2006 Kenworth T300 7.2L 6 Cyl DIESEL. Notes: Heavy-Duty Thermostat -- 190 Degree. Ensure Proper FitTo confirm that this part fits your vehicle, enter your vehicle's Year, Make, Model, Trim and Engine in the Compatibility Table.