Question for G37x with about 400 miles: when I put my driver window down, I hear a strange sound coming from the tires or wheels. I only hear it when going slowly in a parking lot. It sounds kind of like a loud salt shaker shaking. It gets quicker as I speed up. Once I get up to road speed, I can't hear it anymore. I'm not sure if it's only on the driver side, but that's where I hear it as the driver. Any idea of what this could be?

 

stone in wheel ? but not sure where that would be considering the spokes. Perhaps you picked up a stone or nail in a tire. Road noise at speed would cover it up. I would start by examining tires.

 

+1 check your tire .. have someone slowly drive the car with the wheel turned to one extreme or another and look for embedded stones, etc...

 

Nothing on the tire, so I took it to the dealer. Turned out to be the dust cap rubbing against the rotor. All is good now.