Originally Posted by troutslayer
My slide has a rubber gasket at the top of the slide which prevents the slide from direct contact with the RV sidewall. Looks like yours is missing.
+1, I have rubber gasket on the top and down the sides of all slides. So I think you have more of a missing gasket issue than anything else. Without the gasket water can get down to and sit on that buckled tape -slowly seeping in over time.
I also agree with PlayersZ28
: the slide may require adjustment to keep it from closing too tight. However, with proper gasketing this shouldn't be an issue.