Have you ever peddled a bicycle with under-inflated tires and then noticed the difference in effort after you inflated the tires to their proper pressure? Your automobile feels the same way.

How much of a difference in gas mileage does tire pressure make?

Under-inflated tires lower gas mileage by 0.4% for every 1 psi (pounds per square inch) drop in the pressure of all four tires. The fueleconomy.gov web site estimates that drivers can save about 3.3% off their gas costs by keeping their tires properly inflated.

The Tire Rack's Tire Decision Guide is an excellent decision support tool for researching and choosing your next set of tires. The tool enables you to get a good deal on the tires that are best for your vehicle, your road conditions, your tire attribute preferences, and your price point preference. The prices at Tire Rack are tough to beat and they'll even recommend an installer near you.

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