Welcome to iRV2. I'm with the General on this one. While not an annual maintenance task you'll be doing this more than once. Better than taking it to a dealer, see if there is a mobile tech that can come to you. Watch the tech or ask if you can "help". Make sure you know how to do this before the tech leaves.
The tensioner spring is like the spring on a garage door. It is not difficult to adjust, but one needs to understand the process and closely follow it.
If you are parked for long periods of time, consider purchasing several cheap plastic beach balls of appropriate size. Inflate them and push them between the topper and the top of the slide. This will keep everything tight and enhance water runoff.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
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