As the topic says..there is a rattling/grinding noise coming from the front right side of my 2005 s40. It ONLY does this when it is cold (below ~40 F). It does not matter how long I am driving, if it is cold out I hear the noise. I first noticed it last winter, but it subsided in the summer months and is now back.


I notice it the most when driving around town and hitting small bumps in the road. It does not happen, or I can not hear it, at highway speeds. There is also a slight hum/low grinding noise when I turn in cold temperatures.

I have replaced the sway bar endlinks and skid plate (the old one was cracked and I thought that might be contributing to the noise). I have also taken the right wheel of and could not find anything lose or missing. I tried to put weight on it to reproduce the noise and couldn't.
Any ideas?