As the title says, my 2007 V6 Mustang Convertible is getting mediocre gas mileage. Not poor, but not as much as I feel I should be getting. I am getting ~17 mpg in my car with my driving being about 50% city and 50% interstate. My father owns a 2008 Mustang Convertible GT with the V8 and his gets ~20 mpg in a similar driving situation. our driving habits are also very similar. (Neither of us stomp the pedal, take off fast, etc.) I'm not exactly concerned about it, but I feel like I should be getting more out of my gas. My old vehicle, a 1999 Chevrolet blazer, got 15.5 mpg in the same conditions and I was expecting more than a 1.5 mpg difference between a 4x4 SUV and a lighter car... I am planning on seafoaming the car within the next few weeks to clean it out just because, and I am considering replacing the spark plugs but I don't think it needs it (haven't checked them, but I just hit 61k miles and they're stock). Is there anything you guys would recommend? Anything that's a common issue with these mustangs that I should know about? What kind of maintenance should I consider getting done to it soon/now? I can tell you that it runs great, and that the only work ever done to it has been oil changes and a bad wheel bearing. I just got this car about two months ago and I'd love to keep it in great shape. Thanks for any input!