Perhaps the main thing to be sure of, is that the slides are sealing sufficiently when extended. All four slides on our 3400 needed to be adjusted in order to be air/water tight - and the main problem was at the top and upper sides. By the way, the warranty does say that slide adjustment and maintenance is a reponsibility of the owner - and not a warranty issue.
It's pretty easy to check that the slides are properly sealing at the top. While extended,simply use a small mirror to peer down on the top and upper back portion of the slide from the inside. You will be able to see if the inside weather stip is adequately compressed - ours are white rubber that is attached to the inside walls around the slide opening.
Rick & Wanda
2003 2500HD Crew Cab
Duramax with Allison Trans.
Firestone Airbags
Glide-Ride Pinbox - It's Great!
2006 3400RL - We Love The Trailer!
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