Well, after doing the springtime maint. on the wagon, I noticed alot of cracking on the sidewalls of my tires, all within the first inch of the wheel. Now, I see this as a manufacturer defect becasue these tires are ONLY 17 months old and only have 15k miles on an 80K tire. The tire wear is all the same on all 4 tires and even across the tire, so there is no possible question about abuse ( sidewalls are all in excellent condition to--no curb rash). I stopped at the tire shop that put them on and they are calling Yokohama and will get back to me with a possible solution. My thought is that this is a manufacturer defect and there should be no pro-rating of the tires since there is no abuse or issuers on my side of the deal. I will keep everyone informed as to what happens.