I am hearing what sounds like a rattle noise when the car is in drive accelereating at low speeds... it almost sounds like marbles rolling around. I do not believe it is motor sound as there is no noise in neutral or park. In drive you can definately hear it. It is faint but it is there... I do not remember hearing it on the test drive. The noise does not seem to change with rpm. Wondering if anyone else hears this/knows what I am talking about. Car is 4wd with 500 miles on it.