I noticed today when I was in a covered parking structure that I have an odd, intermittent rattling coming from under the car. I've narrowed the problem down to the wheels because it only rattles when the car is moving (in gear or rolling in neutral). It almost sounds like bearings or a lot of small metallic things rattling around. It's not very loud and doesn't seem to be causing any problems (other than the sound). ANY IDEAS?

 

have you checked the control arms and the ball joints?

 

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