Just got back off a trip. Wasn't watching the gas gauge, and the fuel light on my '06 2500 Cummins came on. The DTE said that I had another 43 miles. When I got to the gas station, I put in 33+ gallons. I think it has a 34 gallon tank. That would mean that I should have gotten 43 miles per gallon on the last gallon.
How accurate is the DTE display?
Steve