I was on your home page about bad fuel mileage on the F-150. I have a 97 F-150 Supercab 4X4. I have found that when I change my oil, I add Justice Brothers Oil Treatment with Metal Conditioner and I get about 35 to 40 miles more to a tank of fuel. I also have a friend with a 98 F-150 and by using this additive he had approximately the same results. (I have not tried this with any other oil treatments). I am not indorsing
Justice Brothers; however, it works for me.