Buddy of mine at work just bought a used 2013 laramie 2500 with a cummins and it will not take fuel. Shuts off every few seconds while filling up. After he fills up, gauge on reads 3/4. Not sure if both are related. Since he has a cummins, is there anything to look for here that would cause both? Thinking the fuel level sensor may be at fault for the gauge issue, but I don't see what that has to do with the truck not taking fuel.