6. Consider Diesel
Diesel vehicles operate more efficiently than their gasoline counterparts, because they use higher compression ratios and higher combustion temperatures. The efficiency advantage is enhanced by the fact that a gallon of diesel fuel contains about 10 percent more energy than a gallon of gasoline. These two factors help modern direct-injection diesels achieve roughly 50 percent higher fuel economy than gasoline engines. That’s a big reason why diesel vehicles now account for nearly half of all new vehicle sales in Europe. Diesel still carries a black smoke stigma for many American car buyers, but that’s changing. For now, there are only a handful of diesels, some of which are not available in all 50 states because of strict emission standards at the local level. But expect greater choice in diesel engine vehicles in the next few years.

7. Avoid Gas-Guzzling Vehicle Options
After you select a vehicle segment, and a specific make and model, you’re still not done. If you have a choice between two-wheel drive or four-wheel drive versions, opt for the two-wheel drive. When is the last time you drove a stick shift? Going with manual transmission will earn fuel economy points. And remember that anything adding weight to the base vehicle will result in lower fuel efficiency. Rooftop luggage racks, kayak holders, and ski racks add weight and reduce aerodynamics.

8. New Beats Used
As your car ages, so can its ability to squeeze more miles out of a gallon of gasoline. If your budget allows, purchase new rather than used. Newer cars are more likely to use advanced technologies, such as camless systems, low friction lubricants, idle-stop, and cylinder deactivation, which shuts down cylinders when not needed. Of course, late model used cars can also feature many of these technologies—and can be a great value. Older cars should not be dismissed out of hand. Purchasing used simply means that you need to be careful that the vehicle has been well maintained.

9. Plan Your Shift to Low-Resistance Tires
Don’t just kick the tires. Think about swapping them out with a low-resistance option. The tire offered by the manufacturer is a compromise designed for the widest range of customers. Fuel efficiency aficionados know that tires with lower rolling resistance have a big impact on mpg. See if the dealership will sweeten the deal by making the switch for you. Decreasing the resistance by 20 percent could raise mileage by as much as five percent. No matter what kind of tire you use, proper inflation is essential. For every three pounds below recommended pressure, fuel economy goes down by about one percent.

10. Maintain Your Investment with Good Driving Habits
The EPA window labels say “your mileage may vary” for a reason. The way you drive is every bit as important as what you drive. First of all, don’t speed. Driving 65 mph instead of 75 mph will increase your fuel economy by about 10 percent. In addition, avoid "jack rabbit" starts and anticipate stops. Flooring the gas pedal and speeding up to a red light is a waste of gas. After spending your hard-earned dollars on a fuel efficient vehicle, you don’t want to see your investment get wasted on unnecessary trips to the pumps.