I have been driving a Kia Sportage since May 2008. After about 4 months and 15000 km of driving performance I had a saw tooth formation on my vehicle on all four tires (Bridgestone). After I complained about this problem during the inspection, I was often asked to change the tyres from front to rear or diagonally (running direction bound ? ). Now I have already driven 37000 km my winter tires have the same problem. I try now with a lawyer my Garatie claims through European Union.