Dear Tom and Ray:
When shopping for a new car, we favored the Mazda5, but my wife had one major concern: the low-profile tires. The dealer assured us they were absolutely safe and had standard tires beat. A month after purchasing this car, we caught a hidden pothole, which took out both right-side tires (sidewall bulges), rims, a front strut and a rear shock absorber. In 60 years of driving, having met many a pothole and losing only one tire to them, we've never experienced this degree of damage ($1,800) from a pothole. Are these low-profile tires as safe as standard tires? Or are we the guinea pigs testing these tires? -- Rick
RAY: Are you sure it was just a pothole, Rick? From the amount of damage you did, it sounds like it may have been a canyon at a national park.
TOM: Or, it sounds like you were going very fast when you hit this pothole.
RAY: Or both. When you hit a large pothole at high speed, no matter what kind of tires you have, you're going to do some damage.
TOM: That said, low-profile tires are more susceptible to road hazards. "Low-profile" means the sidewalls are short. This makes the sidewalls firmer, and less likely to bend and deform on turns, which results in better handling.
RAY: But the downside is that there's less space between the road and your wheels. And if you hit a pothole, jump a curb or drive over your neighbor's granite lawn flamingo, you easily could find yourself in need of a new, $800 alloy wheel or two.
TOM: Plus, there are two other things we don't like about low-profile tires. First, they're noisier. And second, the ride is more punishing, because there's less sidewall rubber to absorb the bumps.
RAY: This is something to keep in mind when you're buying a new car. On some cars (like the Mazda5), you don't have a choice. Mazda obviously felt that the van needed the handling advantage of low-profile tires. But sometimes you do have a choice.
TOM: Dealers often will push optional "bigger wheels." But remember, bigger wheels almost always come with lower-profile tires. Why? Because if the wheels are bigger, the tires have to be smaller so the whole shebang can still fit in the wheel well.
RAY: So our advice, in general, is: Unless you own stock in alloy-wheel companies, stick with standard-size wheels and standard-profile tires when you have the option. Your wife was onto something, Rick.