The highest-impact way to lower fuel costs is to lower the amount of fuel needed to power your cars. Weight, drag, and lack of basic functionality can cause your power to require more energy to move. Changing the way you drive can also significantly increase your mileage.
Keep your tires properly inflated. Low-pressure tires take more energy to push down the road. Since the manufacturer tests optimal pressure at cool temperatures, you should check your tire pressure when it's cold outside.
Efficiency increase: 3%.
Take all the junk out of your car. If you have a bunch of items in your trunk that you've simply forgotten about, take them out. It takes more energy to walk with a heavy backpack; the same holds true when you're car's running with extra weight.
Efficiency increase: 2%.
Take off the roof rack. Unless you're currently using it, a roof rack creates unneeded wind resistance.
Efficiency increase: 2%.
Use your air conditioner at the right time. Air conditioners use up a large amount of fuel, but on the other hand, opening the windows increases drag. If you're going under 40 mph, it's much better to lower the windows than use the A/C; over 40 mph, you'll save energy by running the A/C than increasing drag with open windows.
Efficiency increase: 8%.
Don't fill up the gas tank all the way. The more gasoline you put in your car, the heavier it will be. Even though by doing this you'll need to fill up more often, you use less fuel by keeping the weight down.
Efficiency increase: 1%.
Accelerate your car gradually. Remember high school physics – force equals mass times acceleration? It'll take more energy to move a larger object, and to make it accelerate faster. A gradual ramp-up will save you energy.
Try to slow down naturally. Whenever possible, let your car decelerate naturally instead of braking. The car is still burning through gas when it slows down. Braking can cancel out what the car is already using.
Plan ahead while you're driving. Maintain a safe following distance, merge smoothly, and avoid sudden stops to increase fuel efficiency -- and to avoid being that jerk driver.
Hard starts and stops can increase fuel consumption by 40%.
Use cruise control. If you're driving on a highway, cruise control helps you keep a constant speed and avoid expending energy on acceleration or deceleration.
Follow the darn speed limit. Driving over 60 mph increases fuel consumption drastically; according to the EPA, every 5 mph over 60 is like paying 20 cents more for gas.
Efficiency increase by staying under 60: 7% up to 23%.
Find the lowest gas prices. Gas prices vary wildly by station and area; use a map to find the lowest prices within a given range.
But when it comes to saving on the actual gas, think plastic: Many rewards credit cards offer 2%, 3%, and even 5% back on gas station purchases. It's all about choosing the right card. Your best bet is to choose a card that isn't tied to a specific station, because of that price fluctuation thing. Instead, find one that gives rewards on all gas purchases, and preferably one that doesn't impose limits on your rewards earning, if you spend heavily on gas. We've put together a comprehensive comparison of gas cards, taking into account such restrictions and limits.
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