I have kept a record of my gas milage from day one on this car. I has about 47k miles and I have averaged 23 mpg combined driving to/from work and maximum 29 mpg hwy. Since the gasoline prices went up, I did everything I could to squeeze what I could from this car. I have used Lucas Fuel Treatment occasionally with no noticeable difference. Over the last 1300 miles I have used it every fill-up, and my bonafide mpg average is 26mpg. I have had 3 tanks full at 28 mpg including today. I will continue to use this product every fill-up from this point on.