Do a gas mileage study. Fill your tank and zero out your trip odometer. Next time you fill up (and you must fill up when you do this) divide the gallons (to the 10ths) into the miles on your trip odometer when you fill up again. Do this at least 2 or three times and you'll get an average gas mileage figure.......that is if you do basically the same type of driving most of the time. Keep your foot out of the accelerator and drive close to the speed limit. In other words......no racing while you're doing this study. If you do, it could blow the numbers all to ****. Good luck.