Great car, with highway mileage at 65 mph 30 mpg, 24 in town, only small problems. Great to handle on sharp curves, hugs the road. Same battery that came with the car, now have 80,000 miles on it hard to wash though always leaving dirty spots in the creases.
This car is great! The car is very well constructed. I recently got this car as my first car and I wouldn't take anything else. It's pretty fast for being 13 years old and that 3800 Series II engine is a beast. My car personally has trouble starting and the key gets stuck in the ignition. i know the key getting stuck in the ignition is a common problem, but if this happens, there is a hole (you may need to remove a little plastic cover) under where you would insert the key on the steering column. You just use a pen or something, push in the little knob and you can remove the key. There are some websites or videos telling you how to. But this is a great car and would recommend to people!
The Supercharged 3.8 Series II engine is very reliable. 100,000 miles and the engine is flawless, but the rest of the car started falling apart. The Supercharger is not a serviceable item, so when the bearing goes out you have to replace the whole thing ($600 rebuild w/ installation). Both front wheel- bearings needed replacing. Power- steering pump went out. All within 10,000 miles of 100k. The car is definitely worth keeping and repairing. The GTP is the only way to go. If you are considering a Grand Prix, only get one w/ a Supercharger (20% more horsepower than the GT, and it shows). Before buying one, listen to the supercharger, if you hear a grind, get it replaced.