to GM info, their tire and wheel engineers develop GM-exclusive Tire
Performance Criteria (TPC) specifications for each vehicle engineered
in North America to ensure tire performance, handling, and durability
under a variety of driving conditions. Additionally, major tire
manufacturer engineers work together with GM's tire and wheel engineers
during the validation process.
GM uses this research partnership to bring new tires to the marketplace so that tires are properly matched to specific vehicles. That way customers can go to a GM dealership or a national tire brand retail store and order a TPC-branded tire that was engineered to go with a specific GM vehicle.
"Tires are an engineering marvel, with 20 individual compounds and components designed to provide the customer with an optimum blend of performance and durability," says Cowger. "Replacing your tires with anything besides the original equipment Tire Performance Criteria (TPC) specified tire can impact many safety and performance aspects of a vehicle including braking, steering, cornering, ride and handling, noise and vibration, traction and even fuel economy."
Basic Tire Maintenance Tips
Some simple tire maintenance steps can help identify and address problems before replacement is needed, such as:
* Check for uneven wear or excessive tread wear.
* Make sure all tires, including the spare, are properly inflated. Inflate tires to recommended pressure. Under-inflated tires can be a safety hazard, and according to the U.S. Department of Energy, can reduce fuel economy by up to 3.3 percent.
* Properly rotate tires at recommended intervals.
* Properly align and balance wheels.
New Tires are Needed When
Tire wear depends on several factors, including driving style and tire maintenance habits. But one sure way to know when to replace tires is when treadwear indicators appear. A tire's built-in treadwear indicators are "wear bars" that look like narrow strips of smooth rubber across the tread and appear when its time to replace the tire.
A new tire is needed if any of the following statements are true:
* The indicators at three or more places around the tire are visible.
* Cord or fabric is showing through the tire's rubber.
* The tread or sidewall is cracked, cut or snagged deep enough to show cord or fabric.
* The tire has a bulge or split.
* The tire has a puncture, cut or other damage that can't be repaired well because of the size or location of the damage.
Buying New Tires
To find out what kind and size of tires are needed, check the vehicle label. For GM vehicles engineered in North America, the tires installed on each vehicle when it was new had a Tire Performance Criteria Specification (TPC Spec) number on each tire's sidewall. When purchasing new tires, get ones with that same TPC Spec number. If you're not driving a GM vehicle, be sure to follow your manufacturer's recommendation. That way your vehicle will continue to have tires that are designed to give proper endurance, handling, speed rating, traction, ride and performance during normal service on the vehicle.
Each vehicle's owner manual has more information on tires for that specific vehicle, or any Goodwrench dealer can provide tire maintenance services and the correct TPC replacement tires.