I can hear a slight sound that I would describe as metal on metal scraping coming from my rear wheels. By "slight" I mean I only hear it when I'm driving slowly, if EV mode, on a quite street with the windows down. Even then I only really notice it if the sound gets reflected off of a parked car or a building close to the road. Is this normal for a hybrid? I had the dealer look at it and they said it was fine when they test-drove it. I don't really trust the dealer that much yet.