2008 Toyota Prius purchased new: I have done all of maintenance myself, never taken to the dealer or any other shop since I purchased the vehicle. I have the original tires on the car and am currently at 55k. I am a bit anal about tire pressure and rotation. I try to change front to back every 5 k miles and try to keep fronts around 44 psi and back at 40 psi. Also I change the oil at 5k. I still have quite a bit of tread left on the oem Goodyear tires and am about to go on a 3 k trip. I was thinking about replacing the tires as two of four have wear below the specification only on the outer edge. My thoughts on the posts on this board seem to be related to lack of proper maintenance, tirepressure, or bad driving including hitting curbs and such. I honestly don't see how some of you aren't getting the same performance unless you don't take care of your car or are abusing it. I do city, highway, snow, heat and have none of the issues that are described here. If you run into things like curbs your alignment will reduce longevity. I think I can easily get another 10k unless I run over something.