Underinflation of tires, according to studies by the National Highway Traffic Safety Administration, is the leading cause of tire failure and, therefore, tire-related automotive accidents. In short, keeping your tires inflated to the proper pressure is integral for the safety or yourself, your passengers, and other drivers on the road.

There are several reasons tires lose pressure. Tears in the tire wall or punctures are obvious causes of "slow leaks," but ambient temperature can also cause changes in tire pressure as well. For example, if you live in Los Angeles where it is 68 degrees and drive up into the mountains where it is 33 degrees ? a journey of about 1.5 hours ? you can expect a 4.4 psi pressure drop by the time you reach your destination. Why? It's typical for tires to lose pressure at approximately 1 psi for every 8-degree drop in temperature. On top of that, tires regularly lose 1 psi per month as well.

Most of us simply "eyeball" our tires and don't add air until we see a visual difference. This method is not reliable and if fewer people used it as a guide for proper inflation, there'd certainly be fewer accidents as well. In most cars, trucks, and SUVs, the recommended tire pressures are printed on a label in the glove box, on the driver's manual, or on a sticker adhered to the doorframe. Keep a gauge handy and use it regularly. Doing so will not only keep you and your occupants safer, but will also improve your fuel economy.

It's also important to have your tires rotated and inflated to the proper pressure about once every 6,000 miles unless the manufacturer of your vehicle suggests otherwise. Uneven wear on tires can also lead to underinflation.

Some new vehicles now have warning systems to alert drivers of tire pressure loss as a part of their active safety packages. For example, Isuzu's Ascender SUV ? known for its upgraded safety features ? has a Tire Pressure Monitoring System that instantly warns the driver of a significant pressure loss. Isuzu's pickup truck line employs the same technology.

The second leading cause of tire failure is overloading a tire. This happens often with owners of pickup trucks and SUVs. Just because your vehicle can contain a heavy load doesn't mean your tires can support the same amount of weight. Be sure to check maximum load weights and speeds before attempting to haul or tow a heavy load.

Be sure to also use the proper tire for the conditions you're driving in. While it may seem more appropriate to use snow tires on dry roads than regular tires in heavy snow and ice conditions, it's not. Dry roads cause escalated wear of snow tires and reducing traction. It's best to use the proper tires in the proper environments and when the season changes, change your tires as well. "All-season" tires may seem like the most convenient answer, but keep in mind that while they may be adequate in all weather conditions, the nature of their design to do so, keeps them from performing excellently in one specific condition. And because they are not perfectly adapted to any specific weather condition, they may wear more quickly than specialized seasonal tires would when used in the conditions they were designed to function the best.