Does tire size matter?

Automakers are following a growing trend toward bigger tires in the replacement market. Customers who replace standard tires for bigger ones say what they really want is bigger chrome wheels and shorter sidewalls on their tires. That, they say, gives the car a cool side view. Antonius agrees, "When a tire fills the wheel well, it looks good."

There are big downsides to the new tires:

• To boldly hug curves and grip dry pavement, they need shorter sidewalls and complicated tread designs. That makes them wear out faster and cost more to replace, a double whammy for the car owner.

"No matter the vehicle, bigger is almost always better when it comes to wheels and tires," says Rick Brennan, Kumho's high-performance brand manager. "If a midsize sedan can wear a 20-inch wheel and tire package, a large SUV needs an even bigger wheel and tire to achieve the same cosmetic look."