Posted by steel on June 15, 1999 at 02:58:36:
In Reply to: Re: treadwear number posted by MarkC on June 14, 1999 at 12:09:35:
Okay, can't give a complete answer, but I think I can help with some of it. The easy part...the treadware numbers on the sides of tires are DIFFERENT from manufacturer to manufacturer...so for the most part you can toss them out the window. Now you can reasonable hope to assume that a 300 treadware will last longer than a 100. On the other hand, the tires I have now have a 300 treadware and a 45,000 mile warrenty, while the goodyears i took off had a 420 treadware and a 40,000 mile warrenty. So much for nice easy comparisons...the only time you can use treadware ratings is within one companys own tire line (like Dunlops SP4000 vs SP9000, or etc)
OK now some of the reasons for the shorter warrenties have been disputed with me on here before, particularly the argument over if high performance tires have softer rubber compounds. I believe they do. Also, since they are ultra low profile, they have much stiffer sidewalls (better handling, and to protect those bloody expensive rims from getting bent going over unexpected bumps!) Stiffer sidewalls make a driver feel like they can do faster around corners. Corners cause uneven treadware...a problem already since the tire is wider and has a larger contact point. So while the car with wider tires usually feels better in corners, we tend to go faster thru them to um, well, enjoy the corners more. So anyways, these things among others contribute to why tire companies don't want to put much if any warrenty on 17" and above...even if they did it would be short, so there is no reason to do it so they don't because having a tire with a 25,000 mile warrenty would be bad PR and people would think they are junk. SO if you are on 16" you can find some with warrenties, but beyond that, your treadlife is most dependant on your driving and maintenance, cause you are on your own for now...
luck! and don't forget to still have some fun driving those nice wheels...