Hello! My car is a Mercedes Sprinter 213CDI from 11/2001 I bought a set of new summer tires last year (02.04.2011). In winter I drove with my winter kit. In the last weeks the driving behaviour of my car became always more sponge. Especially with wind. I am used to the fact that the car is wind prone, but the extra measure of the last few weeks has moved me to become presumptuous at the DEKRA. I first thought it was something at the wheel suspension but what the Examiner then showed was more than disturbing. 3 out of 4 matures have massive bulges inside and meim 4 starts it already. see pictures. Now I want to go complain next week my tires. But since now a good 13 months have passed since purchase, I would like to know if on the tire is still guaranteed. With batteries it also says, it is only 6 months. Would I be very happy about pertinent ways.