I was driving the car hard this weekend through lots of highways. Added a lot of kilometers on it. Just today after a long rest there came a sort of grinding sound from beneath the car. I don't know where exactly it came from. I felt it from the floor though. But, it could have beeen from anywhere.<p>Has anybody experienced this? I am scared that it might be the quattro system or something.<p>It also sounds like there is something loose from beneath the car. I tried the suspension and the modified exhaust already and nothing seems to be loose.<p>Thanks for any help<p>Patrick Chan