1996 Buick Roadmaster Owner's Manual - Page 263

Buying New Tires To find out what kind andsize of tires you need, lookat the Tire-Loading Information label. The tires installed on yourvehicle when it was new had a Tire Performance Criteria Specification (TPC Spec) number on each tire's sidewall. When you get new tires, get ones withthat same TPC Spec number. That way your vehicle will continue to have tires that are designed to give proper endurance, handling, speed rating, traction, ride and other things during normal service-on your vehicle. If your tires have an all-season tread design, the TPC number will befoliowed by an "MS" (for mud and snow). A CAUTION: Mixing tires could cause you to lose control while driving. Ifyou mix tires of different sizes or types (radial andbias-belted tires), the vehicle maynot a handle properly, and you could have crash. Using tires of different sizes may also cause damage to your vehicle. Be sure to use the same size and type tires on all four wheels. It's all right to drive with your compact spare (if you have one).It was developedfor use on your vehicle. If you ever replace your tires withthose not having a TPC Spec number, make sure they are the same size, load range, speed rating and construction type (bias, bias-belted or radial) as youroriginal tires. 6-41