[ErraticAKn]

I have the 30RKDS in the PNW through the summer and vouch that the trailer being level will help with rain. In heavy rains or days where rain is called on for days I slightly lower the slide-out side to help drain away. Of course every little thing helps, so make sure the rubber isn't kinked, folded or compromised in any way. Like others have said - check the caulking.