Saggy Under Pan

[Chaos1]

I have a 2018 26RBPR I was crawling around underneath and the covered under pan is saggy its just plastic cardboard has anyone else have this issue and if so how did you fix it.Our old 19FBPR was the same but not as bad longer trailer i guess.

[JRTJH]

Coroplast (corrugated plastic) will sag. Usually there's no problem with some minimal sagging. However, if the sag is extreme, the first question would be, "why???".... Is there something inside (above the coroplast) that has broken, fallen out of place? Is there a leaking tank that is allowing water to pool above the coroplast, making it sag? Are there fasteners that have pulled loose, corroded or fallen out allowing the coroplast to sag?

Get under your RV, take a look at the coroplast and see if you can find any reason for the extreme sagging. Pushing up on it should reveal whether there is anything "heavy" like a pool of water above the area. Fasteners are easy to identify and inspect. You might also consider, if you suspect something has fallen out of place, removing a couple of fasteners and using a flashlight to "peek inside" and see what you find.

Let us know what your inspection reveals, then we can give you some advice on how to resolve the problem (if its even a problem). Good Luck

[Chaos1]

Just brought it home so its brand new dealer said some sag is normal but checked it all out seems light no water not to many screws though was just crawling around under re caulking seams and touching up paint before maiden voyage next week (a little ocd i guess)lol. looks like there is not too many cross beams to add any more screws thought of adding a channel down middle

[BamaRam]

Mine was sagging forward of the axles. It must have been flopping in the breeze because the foam sealant around the fresh water drain valve had broken loose. I was able to push up on it about 3" at the valve. So I pushed up on it and the pointy end of a three sheet metal screws poked through the coroplast. I went to the hardware store and picked up some fender washers and sheet metal nuts and used those screws to pull the liner up, then resealed the valve.

[Chaos1]

Thanks put a bunch of screws in, deciding to return it back to dealer to look at it

[Todd 423]

The coroplast liner under my 2020 Raptor is sagging too. I first noticed the sagging at the dealers and their answer was; "that's typical". After I got it home I added wet bolt kit and x factor bracing to strengthen the suspension. So I was under the trailer a lot. It was sagging about the same. I used my RV for several days in the driveway, as if I was camping, and endured a heavy rain storm. I crawled under the trailer again to install sewer hose storage and noticed that there is now water on top of the coroplast liner. I don't know if I have a leak, or the rain somehow found it's way there, or what.