Having the right tires and ensuring that they're inflated properly goes a long way toward maximizing your vehicle's safety, performance and fuel efficiency.

By Samuel Greengard

Head out on the highway, and you're sure to think about what music you've brought along, whether your mobile phone is fully charged and if you have enough gas to reach your destination. For most of us, the tires that keep our vehicle in motion are little more than an afterthought — unless they cause a bumpy ride or one of them goes flat. Yet, having the right tires on a vehicle and ensuring that they're inflated properly goes a long way toward maximizing performance, safety and fuel efficiency.

This is not a trivial matter. Although new cars come with tires that are already matched to the performance requirements of the vehicle, you may want to upgrade to different or more sophisticated tires — either through the dealer or an outside shop.

If you're looking to replace worn tires on an older vehicle, the choices can seem overwhelming. Spending some time researching various designs and finding a tire dealer you can trust can help you get the most out of your investment.

"When you purchase a new set of tires, it's okay to make price a key consideration, but be sure to look for tires that provide the performance level you really want," suggests Jim Davis, a spokesperson for Goodyear North America. "Otherwise, you may get tires that fit into your price goals but fail to make your vehicle ride as well as it should."

Choosing Your Type

There are several different types of tires from which to choose:

• All Season tires are widely used on passenger vehicles, minivans and some small pickup trucks. As the name implies, they perform well under a wide range of conditions, including summer heat and winter cold. They're available in a variety of sizes, but they're not ideal for extreme conditions, such as snow and ice.
• Touring designs are best suited to sports cars. They offer improved handling but are not as versatile as all season tires.
• Performance tires offer superior responsiveness and a sporty appearance at the expense of tread life and comfort.
• Snow tires provide a wide tread pattern with "lugs" that penetrate the snow. Some models offer metal studs for additional traction in icy conditions.
• Truck tires are available in street/sport designs, highway models and off-road tires for challenging terrain.

Another recent innovation is the run-flat tire. These tires are available as original equipment on several automobile models and also as replacement tires. These designs are increasingly popular among safety-conscious consumers, Davis explains. They allow you to drive to the next repair facility at a reduced speed, thus eliminating tire changes on busy roadways, at night and in inclement weather. Other tires may include anti-puncture features or self-sealing technology.

By the Numbers

All the numbers on the side of tires can be confusing, but it pays to know what they mean. If you see a tire stamped with P185/60-R14 82S, for example, here's what it means:

• The P indicates that it's a passenger tire. If it had LT stamped on it instead, that would represent a light truck.
• The three-digit number that follows, such as 185, indicates the width of the tire in millimeters.
• The next number, 60, is the ratio of sidewall height to width.
• R indicates that it is a radial tire.
• 14 is the diameter of the tire in inches.
• The tire's load index, or how much weight it supports, is indicated by 82 (an arbitrary number).
• The final letter, S, is the vehicle's speed rating. In this case, the tire is rated to a sustained speed of 113 miles per hour. An H rating means the tires are rated to 130 mph, and a Z rating indicates they're safe up to 149 mph.

Under Pressure

Of course, not all the action revolves around buying tires. Proper tire care is one of the most overlooked aspects of automobile ownership, Davis says. Regular tire rotation, visual inspections for damage and correct inflation levels are essential.

The National Highway Traffic Safety Administration reports that one in three cars in the United States has at least one underinflated tire, and improperly inflated tires cost the country more than 3.5 million gallons of gasoline each day. In addition, low air pressure will cause tires to wear out much sooner, and it's a serious safety concern, notes Tony Molla, vice president of industry affairs at the National Institute for Automotive Service Excellence.

Many newer vehicles, particularly high-end models such as Acura, BMW and Lexus, offer built-in tire pressure sensors that let you know when you need to add air. Otherwise, buy a gauge and check the pressure at least once a month. Follow the recommendations that are printed in your owner's manual or posted on the doorframe.

It's also essential to check for tire wear. Modern tires include a series of small indentations that are 2/32 of an inch higher than the tread grooves. When the tires become worn, these spots create a visible gap in the groove.

You can also buy an inexpensive gauge at an auto care center or place a penny — with Lincoln's head facing down and into the tread. If you can see all of Lincoln's head, it's time to replace the tire. (It's best to check several treads and also look for uneven wear and bulges.)

If you need new tires, make sure you ask what's included in the price. Otherwise, you may pay extra for balancing, valve stem replacement, installation and road hazard coverage.

Make no mistake, the right tires — when properly maintained — can put a whole new spin on your driving experience.

Bio: Samuel Greengard is a veteran technology journalist based in West Linn, Ore. His articles have appeared in numerous publications, including Discover, Wired, American Way, Hemispheres, Acura Style, Ford Times, and the AAA publications Journey and Westways. 

The views and opinions expressed in this article are solely those of the author and not necessarily those of Progressive Casualty Insurance Company or its affiliates.