This summer, my grandson, Kai Rogers, and I drove to Alaska--Salt Lake City to Anchorage, 3,000 miles. Of course, we went in the thrifty, fuel-sipping Beetle TDI diesel.
Total fuel for the trip to Alaska, 3,000 miles, was 52 gallons. Not bad --- about 57 miles per gallon. On the return trip we did a little better, getting 58 miles per gallon.
I had hoped to do better. Here in the western states, my summer mileage is consistently about 60 miles per gallon. We surmise that the reason is the difference in climate. It would be necessary to use a little different diesel fuel blend in northern Canada and Alaska to insure that the fuel doesn't solidify if the weather were to suddenly turn cold. Cold-weather fuel contains a little less energy than what we use down around Utah in the summer time.
You can follow the link to my car's web page to see some pictures and hear more about the trip.