Tire size 1999 Pontiac grand prix gtp?

The tire size for a 1999 Pontiac Grand Prix GTP depends on the options selected when the car was originally manufactured. There wasn't a single standard size. To know for sure, you should:

* Check the sticker on your driver's side doorjamb. This sticker will list the recommended tire size for your specific vehicle.

* Check your owner's manual. It will also specify the recommended tire size.

* Look at the sidewall of your current tires. The size is printed directly on the tire sidewall. This will tell you what's currently on the car, but it might not be the original or the *recommended* size.

Without checking these sources, I can't give you a definitive answer.