Myth #4: Always Overfill Your Tires

This car myth masqueraded for decades as an insider’s tip for getting better gas mileage with less wear and tear on your tires.

You want to keep your tires at the recommended pressure because if they’re over-inflated, they wear one way, under-inflated they wear another. Try to get even wear and rotate your tires every 7,500 miles. On the other hand, it doesn’t make a whole lot of difference on mileage. As far as wear goes, it’s better than under-filling them, and the reason is, for every pound that a tire is under the recommended pressure, it will run hotter and wear faster. If you ran a tire five pounds under the recommendation, it would last probably 20 percent less.