While some commuting Americans might turn to public transportation or carpools, many drivers live in areas that require cars.

But drivers can take steps to maximize their fuel economy.

One big problem?

Only 19 percent of drivers properly check their tire pressure, and poorly inflated tires cost Americans an unnecessary $1.1 billion each year. That's equates to 3.5 million wasted gallons of gasoline each day.

Properly inflated tires could save drivers $2 every time they fill up, getting the average passenger car an additional 10 miles per tankful.

To help maximize fuel economy and improve tire performance and efficiency, Goodyear is offering free tire inspections - regardless of brand - as part of its national "Free Air" campaign.

Consumers can get their tires checked at any of Goodyear's 750 company-owned, and at participating independently owned and operated, Goodyear locations across the country. If tires are underinflated, they will be filled at no charge - no appointment necessary.

Goodyear offers other helpful tips to improve gas mileage:

- Check the air filter. A clogged air filter can reduce a vehicle's fuel efficiency by 10 percent. A clean filter also keeps impurities from the engine, improving its performance and lifespan.

- Remove junk from the trunk. Overpacking a vehicle beyond its manufacturer's recommended weight costs gas money. Carrying 100 extra pounds in the trunk? That reduces a car's fuel economy by 1 to 2 percent.

- Drive peacefully. Aggressive driving - speeding, slamming on the breaks, fast acceleration - can reduce highway gas mileage by 33 percent.

- Use the right oil. Vehicle manufacturers recommend motor oil grades for a reason. Using the right grade can improve a car's mileage by 1 to 2 percent.

- Tune In. Drivers should maintain their vehicles. According to the U.S. Department of Energy, regular tune-ups can improve gas mileage by 4.1 percent.

To learn more about Goodyear fuel saving tips and the "Free Air" Campaign, visit www.goodyeartires.com.