We just got 8.3 mpg on the 3300 mile trip to Tucson. 12,000 Lbs 78 Royale 403. ( I think the Royales are the heaviest in the range of 1000 lbs extra weight.) Then a 5,000lbs Chevy Uplander handicap lift van on a dolly. We never travel without towing something. So I have no idea on the towing loss. The Tracker is half of our modified Uplander. Weight plays in. But so does the shape of what your towing. Bob Dunahugh