To get better gas mileage all you need is air.
That's right, air.
Not in your car, but in your car's tires.
"The number one thing I think is proper tire inflation," said mechanic Tim Kotter.
It's one of those areas that people often forget when it comes to getting better mileage. But Kotter says when you're pushing a car you really notice the difference.
"They don't go down the road as smoothly," said Kotter who says once you add the proper inflation, "it feels like a different car."
But how do you know how much air to put in the tire? Don't trust the "psi" number on the tire itself but look at the owner's manual or on the sticker in the driver's side door jam.
What about keeping your car in idle instead of stopping and restarting?
"If it's a fuel injected engine," said Charles Langley with the consumer group UCAN, "it's probably cheaper to shut if off after about 35 or 40 seconds.