1997 Pontiac Bonneville Owner's Manual - Page 299
1997 Pontiac Bonneville Manual
Page 299 highlights
Buying New Tires To find out what kind and size of tires you need,look at the Tire-Loading Information label. The tires installedon your vehicle when it was new had a Tire PerformanceCriteria Specification (TPC Spec) numb'eron each tire's sidewall. When you get new tires, get ones with thatsame TPC Spec number. That way your vehicle willcontinue to have tires that are designed to give properendurance, handling, speed rating, traction, ride andother things during normal service on your vehicle. If your tires have an all-season tread design, the TPC number will be followed by an "MS" (for mud and snow). Mixing tires could cause you to lose control w: e driving. If you mix tiresof 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 to use the same size and type tireson all wheels. It's all right to drive with your compact spare, though. It was developed for use on your vehicle. If you ever replace your tires with those not having a TPC Spec number, make sure they are the same size, load range, speed rating and construction (bias, type bias-belted or radial) as your original tires. 6-46