Bridgestone/Firestone's traveling classroom keeps tire
retailers informed. Learn what we learned when we tagged along.
The traveling Bridgestone/Firestone Drive & Learn program operates in order to keep tire retailers up to date on current products and the official company line on tire maintenance and safety and will make 15 stops in 2008.
 Image courtesy Bridstone/Firestone |
In addition to the instructive presentation, participants
were given autocross-style track time to compare Bridgestone's product to
the competition. Representing front- and rear-drive cars were Volkswagen GTIs and BMW 328s, respectively. Participants were
able to compare, back-to-back, tires from Bridgestone/Firestone,
Michelin, and Yokohama.
Here's what Consumer Guide learned:
Tires Matter
As simplistic as that sounds, it is amazing how differently similarly-priced tires from two manufacturers can behave under identical circumstances. Unfortunately, most shoppers will never have the opportunity to test drive the tires they are considering.
If you are buying new tires, you likely had 50,000 or more miles to become familiar with the rubber on your car now. Stick with what you know. Ask your retailer for the closest match to the tires you are replacing. Replicating the feel and behavior of the tires you are accustomed to will likely be an asset when driving conditions turn ugly.
People Ignore Their Tires
For most drivers, the biannual trek to Jiffy Lube constitutes the sum total of their tire maintenance regimen. A recent Bridgestone/Firestone survey of 12,000 randomly selected vehicles revealed the following:
- 27 percent of cars surveyed had one or more tires under-inflated by at least eight psi.
- 33 percent of trucks surveyed had one or more tires under-inflated by at least eight psi.
- Three percent of cars surveyed had all four tires under-inflated by at least eight psi.
- Six percent of trucks surveyed had all four tires under-inflated by at least eight psi.
Tire Pressure Monitoring Systems Only Work So Well
Federally required on all new cars and light-duty trucks in calendar-year 2007, Tire Pressure Monitoring Systems (TPMS) alert drivers when one or more tires becomes under inflated. "But the systems can only do so much," said Larry Stevens, spokesman for Bridgestone/Firestone. "The most common systems won't act until a tire is more than 25 percent under inflated, and that's already a dangerous situation."
Stevens also noted that most tire pressure systems work through a vehicle's ABS system, measuring inflation by comparing wheel rotation speed. This system could thus be fooled if all four tires became under inflated simultaneously, and therefore, issue no warning.
Tire Pressure Changes Quickly
According to the Bridgestone/Firestone technical staff, a tire will lose one psi a month, just through normal seepage. Plus, tires typically lose one psi for every 10-degree drop in temperature. By example, unchecked tires on a Chicago-area car could lose 10 psi between July and December.
 Image courtesy Bridgestone/Firestone |
There's More to Tire Replacement Than you Think
Ideally tire dealers would prefer to sell you four tires at a time. Additional revenue is one reason, but safety plays a factor here, too. A car is safest when all four tires are similarly worn.
Because front and rear tires wear at different rates, and because customers would rather not finance four tires when two will suffice, tires are often sold only in pairs.
Bridgestone/Firestone always recommends placing the new tires on the rear axle, even on front-drive vehicles. The reason for this is a handling dynamic known as oversteer. Simply, a car is said to oversteer when the rear is more likely to lose traction in a corner than the front. Oversteer is considered especially dangerous and best avoided by placing the tires with the greatest traction on the rear axle.
Paying Attention Pays Off
No car owner can reasonably be expected to fully understand the physics of replacement tire location and crash avoidance, but most should be paying more attention to their tires. Regular tire inflation checks are a simple way to improve your odds of avoiding a dangerous situation, and may pay off in extended tire life and improved fuel economy.
Bridgestone/Firestone dealers (and a number of other retail tire chains) offer customers free rotations for the life of tires purchased from their stores, and will gladly check the pressure in your tires, should you be driving by.
In a nutshell, drivers need to pay attention to the simple stuff like monitoring the pressure in their tires. For the big stuff, find a tire retailer who answers questions to your satisfaction and whom you trust.
Updated by Don Sikora II 08.07.2008
