Originally Posted by JBHorner

There are some freeways in the Los Angeles area that will toss cars from side to side. One of know of is the 91 in some places, and the 605 in some places. I've had this happen with a number of vehicles, big and small. (Inclusive of my X5.) It's not really bad, but it is obvious.

I believe it is the ridges that are cut into the road to negate a perfect hydroplane environment. The tread of the tires, I think interacts with the ridges and moves the vehicle very slightly.

I'm not sure where you're located, or if this is even the issue. I'm only giving my own experience.

Joel