Wheel Related Problems of the 1998 Ford Explorer Sport

Wheel problem

These tires are still under warranty. When they were first installed, we noticed a strange sound. We did not assume it was from the tires, but thought it was related to the rotors. This is not our only vehicle and we don't drive it all of the time; in fact it is parked much of the time. We did not get the rotors replaced until August of 2013. The sound continued even with the new rotors, to our surprise. So we went back and checked a second mechanic who then removed all of the tires. After inspecting the tires, the mechanic showed us where they were defective. He physically pointed out some areas where they were deformed. He told us to take them back to where we purchased them for replacement. In short, we were not able to get them replaced at wal mart where they were purchased. I would like these tires independently inspected so that we can verify that they are indeed defective. Thank you.