whenever i drive over bumps of any size there is a loud noise that sounds like rattling from the front end. I can feel it a little in the firewall, however when i lift the car and grab parts nothing seems to rattle. I recently replaced the bushings on the sway bar and sway bar stabilizers. has anyone had this problem, something similar, or any idea what this is. the noise is driving me crazy and the fact that i can't pin point it is that much more annoying. please help.