Ive got an 07 Malibu ls. For quite some time now I have had this frt end noise. Its a tapping rattling noise on fine bumps. Here is the strange thing. It only happens in the winter and then only for a while when I start driving. It kinda goes away as I keep going. When its very cold it doesnt quite go away but gets lots less as the car is driven for a while. Ive checked everything in the front end including sway bar links. Ive made sure the brake calipers arent loose. Ive had it checked out at a reputable shop. Of course as soon as the car is inside a warm shop, it wouldnt make the noise anyways. They have not been able to pinpoint it either. Any body else had this? What was the solution?