that has been their responce since i was looking into it. i don't expect there wouold be any problems running the b-20 other than the fuel filter element needing to be changed. ive been waiting for my warrenty to run out or the price of biodiesel to be lower than reg #2 before i run it. the guy at the fuel station says he sees lots of cummins pickups useing it... and he also says when it come to warenty covereage... don't ask don't tell