I will soon need new tyres so have been looking at some of the tyre manufacturers websites. None of the ones that I looked at gave any information on DOT Quality Grades for their tyres; Treadwear, Traction(A,B,C), or Temperature(A,B,C) What is going on ?
http://www.tirerack.com/
is a good place to get that info and more.
www.carbibles.com is another good site for information on tire markings.