Driving aggressively (including braking and accelerating suddenly) wastes gas, and every 5 mph you drive over 60 mph is like paying an additional 20 cents per gallon, according to fueleconomy.gov.
Keeping your tires properly inflated reduces fuel use by 3% to 4%, according to Ford Motor Company's Eco-driving tips. Also, filling your gas tank during cooler times of the day gets the most bang for your buck and prevents fumes from heating up and creating ozone, the EPA advises.
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