....It happens everytime I'm in the car - it comes and goes, although its becoming more common now. It's a subtle grinding sound, with a slight rattle sometimes mixed in. Any ideas? It happens at any speed - not just braking or cruising; although it isn't very loud.

I was guessing a bearing or brakes hanging up. The car has 40,500 miles on it, all of which I put on, if that has any significance. I haven't hit any pot holes or bumps either.

Thoughts?