My wife says she hears a knocking sound which gets a little louder on a bumpier road. She says it feels like its under her feet while driving. I am out of town and have not driven it myself, but if any one has ever experienced it and know's what it might be, please help me out! We have 2 kids and she is pregnant and I dont want something to happen to the car while she is driving and cause an accident. So the sooner someone can respond the better, thanks!!!