Hello. I am a Diesel enthusiast currently driving my New Beetle TDI daily on a 17 mile one-way commute down the highway. For the past half dozen tanks or so, I have been buying Shell fuel and my average has been 46 MPG, calculated by hand. I am really wanting to hit that magical 50 MPG mark and every tank, i say, "I'll swap over to the Jetta tires this time," then am too whipped at the end of the day to do it. THe beetle tires are 16s and wider than the Jetta tires, so between those two factors, I should be able to get to 48 easily. I drive at about 57 MPH until I hit the construction for the last five miles, then it's 48 MPH. No stop and go in the constuction zone and it's only on the way to work, so my commute is about 34 miles R/T with the last 5ish under 50 MPH. I do use the Cruise control so I know I could be picking up a little bit there because I'm smarter than the Computer, I'm just less focused. Anyway, I think I saw a place to track my mileage, so I'll go check that out.