"Since it is a 2001 you might want to do a pressure test to find all the leaks."
Exactly. I bet it's leaking and I bet it has rot issues, how bad will depend entirely on if the original owner kept up on the seals but I doubt that.
TT's are no exception either, they also have forward facing seams that leak.
Really easy way to tell is pull the vinyl insert trim that fits in the extruded moulding and take a hard look at the screws. If any are rusty, it's leaking and you can buy the trim in rolls for replacement.