I have a 05 S60 AWD, and when it is raining and I drive through a mid size puddle in the road, the car develops a bad vibration. I don't feel it in the steering wheel. It will continue until the car is parked for awhile, and it goes away. But it will continue as long as I drive the car. The fast I go, the stronger the vibration. Has anyone else run into something like this? It only happens when real wet. Otherwise, it is quiet as a mouse.