In my '00 X, I get 16.7 MPG daily driving (highway + city driving).The closer you keep it to 70 MPH, the better your fuel economy will be. My best is 19.5 MPG. With a 44 gallon tank, that will take you over 800 miles without having to fill up. I normally see about 16.5-17 on the highway mainly because the speed limits are 70 or 75 where I drive, and you can get away with 80-85. 75 MPH and higher and the fuel economy starts to drop off.