I have a 99 SHO with almost 37K. There's this rattling noise that sounds like it's coming from the driver side rear door but I can't seem to pinpoint it. It seems to be riding a bit rough too, not the engine but the car itself, like it's a truck or something. It's really getting on my nerves and I'm wondering if anyone can tell me what it could be. I'm worried that it might be something in the suspension. Any guesses? TIA for your input.