1998 Chevrolet Blazer Owner's Manual - Page 315

Uniform Tire Quality Grading Mixing tires could cause to lose control while you driving. If you mix tires of different sizes or types (radial and bias-belted tires), the vehicle may not handle properly, and you could have a crash. Using tires of different sizes may also cause damage to your vehicle. Be sure touse the same size and type tires on all wheels. It's all right to drive with your compact spare (if you have one). It was developed for use on your vehicle. The following information relatesto the system developed by the United States National Highway Traffic Safety Administration, which grades tires by treadwear, traction and temperature performance. (This applies only to vehicles sold in the United States.) The grades are molded on the sidewalls of most passenger car tires. The Uniform Tire Quality Grading system does not applyto deep tread, winter-type snow tires, space-saver or temporary use spare tires, tires with nominal rim diameters of 10 to 12 inches (25 to 30 cm), or to some limited-production tires. While the tires available on General Motors passenger cars and light trucks may vary with respect these to grades, they mustalso conform to Federal safety requirements and additional General Motors Tire Performance Criteria (TPC) standards. A CAUTION: If you use bias-ply tires on your vehicle, the wheel rim flanges could develop cracks after many miles of driving. A tire and/orwheel could fail suddenly, causing crash. Use only radial-ply a tires with the wheels on your vehicle. 6-45