I just got home after a 500 mile weekend trip. The first half of the trip was all highway at 75 mph, removed a 7000 lb boat from the water and towed it 2 miles to a gas station for fuel, then two miles back to the launch. The rest of the trip was at 70 mph home. averaged 19.0 mpg for the entire trip. Total miles on my 06 LBZ right now is 3,300. Ed

No towing except for the 4 miles with the boat.