1996 Buick Park Avenue Owner's Manual

Mixing tires could cal ! you to lose control whiledriving. If you mix tires of different sizes or types(radial and bias-belted tires), the vehicle may nothandle properly, and you could have a crash.Using tires of different sizes may also causedamage to your vehicle. Be sure to use the samesize and type tires on all wheels.It’s all right to drive with your compact spare,though. It was developed for use on your vehicle.Uniform Tire Quality GradingThe following information relates to the systemdeveloped by the United States National HighwayTraffic Safety Administration, which grades tires bytreadwear, traction and temperature performance. (Thisapplies only to vehicles sold in the United States.) Thegrades are molded on the sidewalls of most passengercar tires.The Uniform Tire Quality Grading system does notapply to deep tread, winter-type snow tires, space-saveror temporary use spare tires, tires with nominal rimdiameters of 10 to 12 inches (25 to 30 cm), or to somelimited-production tires.While the tires available on General Motors passengercars and light trucks may vary with respect to thesegrades, they must also conform to Federal safetyrequirements and additional General Motors TirePerformance Criteria (TPC) standards.TreadwearThe treadwear grade is a comparative rating based onthe wear rate of the tire when tested under controlledconditions on a specified government test course. Forexample, a tire graded 150 would wear one and a half(1 1/2) times as well on the government course as a tiregraded 100. The relative performance of tires dependsupon the actual conditions of their use, however, andmay depart significantly from the norm due to variationsin driving habits, service practices and differences inroad characteristics and climate.