Put the right rubber on the road

Surveying the sidewall
The stiffness of the tire's sidewall is the single most important factor in how it will ride, explains Wesoloski. While tread and tread pattern will help a tire grip the road, how it does that is affected by how the sidewall bends and collapses out of the way.

"The Corvette driver demands traction performance so he wants a stiff tire, whereas the Buick Century driver wants tires that will maintain traction for safety purposes, but he isn't likely to be driving under high-speed conditions and he doesn't want a stiff tire that will result in a harsh ride," Wesoloski says.

If you've selected a car like GM's Grand Prix or Monte Carlo (not really a sports car, but more performance-oriented than a Buick Century), Wesoloski says your choice of tires will change the personality of the car.

Put a performance tire designed to give better traction on these sedans and you've got a sporty ride and handling. But buy passenger tires if comfort is the goal. In Wesoloski's case, he had performance tires on his Monte Carlo SS until he got married and turned that car over to his wife, who complained that the ride was harsh. So he switched to tires with a softer sidewall.

"Now it's like driving my couch down the road," he jokes.

In general, the more rubber you put on the road, the more stable the vehicle will be. But Wesoloski believes that opting for the big rims and low-profile tires that have become a popular SUV and sport truck option won't help increase traction.

"It's an appearance, not a safety issue," he says.

He advises against off-road tires unless you're really going into the outback. If the only off-roading you're going to do is when you accidentally back over the flowerbed, stick with the standard-issue, all-weather truck/SUV tires, or even choose passenger vehicle tires.

"The tires these trucks came with have three or four inches of rubber showing on the side that give the tire more room to flex, and that gives you a much more comfortable ride," he says.

Matching tires to your driving style
Online tire retailer Tire Rack, whose headquarters is located near the racing capital of Indianapolis, started out in the tire business 20 years ago selling specialty tires to racers and car collectors. Today, Tire Rack maintains a testing facility, an online database of tire evaluations and has expanded its sales to consumers.

Matthew Edmonds, Tire Rack's director of marketing, says the tire industry makes it confusing for anyone buying replacement tires because even though a tire has the same name, it may not be the same tire everywhere it is sold. That's because tire manufacturers tailor tires to the requests and limitations of their customers: auto manufacturers and retailers.

Instead of trying to sort through the confusing array of numbers in an effort to match original equipment, Edmonds suggests that you shop for the tire that best reflects your driving habits. If, like most people, you do some of your driving on city streets and some of it on highways, an all-weather tire may be the best choice. But if you spend a lot of time on rough roads, drive often in rain, snow or icy weather or never go beyond the city limits, you may be happier with a more specialized tire.

"Even if you and I drive the same car in the same city, I may be concerned with how comfortable the car is, while you may be willing to sacrifice comfort for good handling around the turns and a performance feel," Edmonds says.

If you decide to change to a size other than what the manufacturer recommends, be particularly cautious. While a larger size will give a car a sportier look, tires and suspension work together. If the tire rubs or otherwise impedes the way the suspension works, at best you'll wear out the tires quickly, and at worst you could lose control in wet or snowy conditions. If you really have your heart set on larger tires, Edmonds suggests having two sets: the larger tires for the good-weather months and the recommended size with heavy-duty tread for the winter months.

Before you buy, do some research. Each tire manufacturer has a Web site that will help you identify a recommended range of tires available for your car. Tire dealers also often offer online advice and tools to help you determine your tire needs and compare options. Tire Rack's Web site, for example, will give you an evaluation and make recommendations about a number of brands.

It also might help to talk to a knowledgeable tire dealer, although remember that he probably sells only a few of the available brands. Compare prices at three or more tire outlets. Prices vary enormously.

Keeping the rubber on the road longer
Regardless of the type of tires, proper care will help keep them -- and your car -- on the road longer. One easy, but usually neglected, maintenance task is checking inflation.

When a professional racer complains that his car isn't handling well, technologically complex corrections usually aren't required. In most cases, a simple tire pressure adjustment will ease the problem.

Rising NASCAR star Ryan Newman, with a degree in vehicle structure engineering from Purdue University, relies on Goodyear to keep his race crew informed on the recommended air pressure for each track. "We are forever putting air in and taking air out to see how the car reacts on the race track. You never want to go too high or too low on pressures because it can do some big damage," says Ray Osian, tire expert for Newman's Dodge ALLTEL team.

Consumer tire experts say ordinary drivers should be as concerned as Newman and his colleagues about tire pressure because proper pressure will determine the life of the tire as well as the way it rides.

"Rubber is permeable and if the temp drops 30 degrees, tire pressure goes down. After three winter months, your tires probably dropped six pounds. If you're driving in snow or ice, that kind of low tire pressure can be extremely dangerous," Edmonds says.

Check your tire pressure often, with an accurate gauge, for routine driving and before and during any long trips. Measure the tire when the tires are cold, before you drive on them. The recommended inflation pressure can be found in your owner's manual or on a label frequently found in the glove box, near the door latch on the driver's side, or other locations on your vehicle.

Other tire safety tips from the U.S. Department of Transportation include:

A careful examination of your driving style, traffic needs and maintenance requirements will ensure that your tires keep you and your car on the road for a long time.

Jennie L. Phipps is a contributing editor based in Michigan.