My car was making a roaring noise from the rear of the car starting at about 45 mph and increasing in volume as the speed increased. The Honda dealer in downtown Dayton said all my tires were slightly cupped, so Michelin partially paid for a new set of tires. The noise didn't go away and actually sounded worse. The dealer checked the tires and the rest of the car and said nothing was wrong. They even said they couldn't hear the sound. I then took the car to 3 other places and all of them said the sound was normal and nothing was wrong. After suffering for months with the noise that "only I could hear", I took it to another Honda dealer, who heard the noise and said the transmission needed replacing. So under warranty they replaced the transmission, but that didn't fix it. After that, the service manager and I drove the car together and compared it to another used car just like mine on the lot. The next day, they fixed the problem by replacing the right wheel bearing. Now my car is like new again. In fact I don't think it was ever this quite the day I bought it brand new.