I too have used an air deflector wing for the last 2 years on my 7.3 '02 Excursion. I echo Forest's analysis and agree with his excellent assessment. I pull a 32 foot Outback travel trailer and it pulls like a dream. I have a 6 inch all spring Skyjacker lift, with Air Lift air bags in the rear, 37 inch Nitto tires, a weight distributing and sway control hitch, with a 120 hp DP Tuner. The wing provides stability, keeps the bugs off the front, and helps with milage. Thanks Forest.