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Old 11-14-2019, 08:49 PM   #1
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What's going on under the back of my 5er

I would appreciate someone taking a look at these pics and providing some direction. I notice the black plastic hanging down and found the bent metal and screws backing out. We purchased this (3931FB) new in Feb. Thanks for taking a look.



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Old 11-14-2019, 09:03 PM   #2
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It's called "vibration" and you better get use to it Your home on wheels tries to self destruct every time it goes down the road. It looks like it's just screws backing out. You should replace any that are missing and check the rest for tightness. If the screws won't tighten then you can replace them with one size larger. Seriously, you just need to keep a constant vigil on ALL of the fasteners on your trailer, as it's a never ending task to keep them tight.
Actually, after looking at your model year you might have nails holding the coroplast. If that's the case you can replace them with self tapping screws. Any nails that are starting to slip down should be pulled out and replaced with the screws instead of being pounded back in. Good thing you caught it early while it's still an easy fix.
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Old 11-14-2019, 09:07 PM   #3
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Had ours coming down like that, but ours was because they had cut the coroplast wrong and it didn't hit the metal frame some of the way across. I fixed it by screwing a door sill on there to bridge the gap. From what your pictures show I'd either put screws back in place with some fender washers or use the sill treatment. My problem is I can't identify what that is hanging down in the middle picture and that concerns me.
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Old 11-14-2019, 09:20 PM   #4
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The piece hanging down is black corrugated plastic. There's another small piece on the left side. It think it may be part of the large underbelly covering.
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Old 11-14-2019, 09:40 PM   #5
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Use stainless steel screws and washers.
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Old 11-15-2019, 08:08 PM   #6
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Mine did the same. I reattached mine with self tapping screws. Looked like they cut mine a little short.

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Old 11-16-2019, 08:40 AM   #7
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Put a dab of silicone on the self tapping screws when reinstalling and they likely won't back out anymore. It seems to help absorb the vibration..... worked for me...
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Old 11-16-2019, 09:44 AM   #8
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Our HC had the same problem though not quite as bad. I 'temporarily' fixed it with Eternabond tape - then forgot about it until this thread. Oh well, spring is just around the corner

Oh and that gap, it's nice open doorway to critters and most likely whay we had mice this spring since the extension cord I use to keep the battery charged, hooked the corner, probably when I used the snow blower and moved the cord. Made for a nice walkway.
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Old 11-20-2019, 03:51 PM   #9
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I used 1 1/2" angle ,the kind with holes already in it. Mine was left open some by the repair shop and I didn't want cold getting in freezing my water or the stink-bugs getting in.
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Old 11-21-2019, 08:44 PM   #10
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Another point to be aware of. The black plastic undersheath is constructed much like corrugated cardboard. On my unit the open ends of the corrugation was on the sides of the unit. While traveling in the rain, water spray from the roadway / tires filled the corrugated channels. The weight of the water in the channels caused the underbelly to sag greatly. While parked at a RV site I was able to raise the center area of the underbelly and drain most of the water. After couple weeks of no rain and apparently dried out, I sealed the ends or edges of the underbelly plastic corrugations with black silicone caulking. So far, no more problems.
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