I was driving home from work today on the highway and it started to sound like I had a flat tire. I pulled off the highway and checked and no flat. I could smell the faint smell of burning rubber. Checked the tires and could see no problems. It did it again before I got home after I picked up speed again, a lot of really loud road noise. Called my father in law and he said it sounded like maybe one of the tires is seperating. So i took it to a little po-dunk shop here in town and the kid jacked the car up and spun all 4 tires and said he didnt see anything wrong. Any ideas?