My '04 XC90 has developed a water sloshing sound under the floorpan. The noise is noticeable when braking, presumably when the water moves. There are no leaks under the car. The only thing that is new is that the car was kept outside for a week, when it rained. I also have running boards, and I was wondering if they are hollow and have water in them, or whether it is something more ominous. My brother's XC90 had a sunroof leak that drained into the floorpan. Is this the same problem? Anybody know the fix? Advice please!<br>Thanks.