I think I have the oldest TL in this thread 9/03 800. I bought it third hand from a couple on Long Island, and a storm called Sandy! I found rot under the two driver side jack stand supports. I got a bucket full of what looked like wood mulch from where the support structure was supposed to be. I blamed this on Sandy. I replaced all the bad wood with new, knock on wood (pun intended) everything is fine now. I think I should do a pressure leak test soon.
We have tweaked a few things to our tastes, a curtain in place of the bathroom door, replaced all lights with LEDs.
Otherwise we love to camp in our TL TC.