I've been considering buying a five or six year old smaller fifth wheel and looked at two nice ones yesterday that had a spongy feel on the outside rear wall. One was a 2013 Wildcat and the other was a 2015 Cougar. Both were 30 footers with a large rear window and below the window the fiberglass exterior would flex in and out when I pushed on it. Both sides of the window and above it and the rest of the walls felt firm and looked good. They were at two different dealers and the salesman at both told me that was fairly common on these models with large rear windows. Anyone had any experience with this that can give me some advice? Thanks

I know those walls are typically of a "hung" variety, but I don't think they should be any different firmness than the side walls! I may be wrong, but I would suspect a small amount of water intrusion from the window or roof has made it spongy. Other potential issue is the wall materials have delaminated due to glue/adhesive failure. Not sure I would proceed much further without an independant inspection. Buying an rv with a leak or delamination puts your investment in jeopardy.

Thats normal for a non bonded wall. The only things holding the outer layer to the 5er are the window, perimeter trim and lights. Or whatever else penetrates the wall.

The window has probably leaked. Also check the roof especially around the corners and ladder area. Check under the slides for soft or crunchy areas when you push up. Very common at the ends. Sometimes they leak and dry out and leave raised/bumpy crunchy areas.

goducks10 wrote:Thats normal for a non bonded wall. The only things holding the outer layer to the 5er are the window, perimeter trim and lights. Or whatever else penetrates the wall.Yes, many FWs with bonded firm sidewalls, do not have the same across the back. You can press on the inside back wall, and likely feel more give, than at the sidewalls. If no sign of water intrusion around rear window, inside or out, the units mentioned should not be a problem.Jerry

Exterior rear wall feels spongy | Good Sam Community

FLY_4_FUN
Explorer
Mar 29, 2019
I know those walls are typically of a "hung" variety, but I don't think they should be any different firmness than the side walls! I may be wrong, but I would suspect a small amount of water intrusion from the window or roof has made it spongy. Other potential issue is the wall materials have delaminated due to glue/adhesive failure. Not sure I would proceed much further without an independant inspection. Buying an rv with a leak or delamination puts your investment in jeopardy.
pianotuna
Nomad III
Mar 29, 2019
Run away.
goducks10
Explorer
Mar 29, 2019
Thats normal for a non bonded wall. The only things holding the outer layer to the 5er are the window, perimeter trim and lights. Or whatever else penetrates the wall.
azrving
Explorer
Mar 29, 2019
The window has probably leaked. Also check the roof especially around the corners and ladder area. Check under the slides for soft or crunchy areas when you push up. Very common at the ends. Sometimes they leak and dry out and leave raised/bumpy crunchy areas.
MFL
Nomad II
Mar 29, 2019
goducks10 wrote:
Thats normal for a non bonded wall. The only things holding the outer layer to the 5er are the window, perimeter trim and lights. Or whatever else penetrates the wall.

Yes, many FWs with bonded firm sidewalls, do not have the same across the back. You can press on the inside back wall, and likely feel more give, than at the sidewalls. If no sign of water intrusion around rear window, inside or out, the units mentioned should not be a problem.

Jerry
WNYBob
Explorer
Mar 29, 2019
Yes that's'delamination', so drop the price $6 to $10, because that is what a dealer would sock you on trade in!
Ralph_Cramden
Explorer II
Mar 29, 2019
WNYBob wrote:
Yes that's'delamination', so drop the price $6 to $10, because that is what a dealer would sock you on trade in!

It may be, but most likely just the way its designed and built as at least two others have posted in this thread. If you go look at laminated trailers on a dealers lot you'll see the bows and waves in the rear walls on most of them, just look from an angle. The only manufacturer I am sure of who uses a true laminated panel the same as the sidewall for rear walls is Rockwood / Flagstaff. There has to be others.
bingford
Explorer
Mar 29, 2019
If it's a composite bonded wall then it should be solid. Some rear walls are of a 'floating" design and have some give. However it would be uncommon to have a large window on this type of wall.
goducks10
Explorer
Mar 29, 2019
WNYBob wrote:
Yes that's'delamination', so drop the price $6 to $10, because that is what a dealer would sock you on trade in!

I know for a fact that Keystone does not vacuum bond or pinch roll the rear walls on Cougars. It's not delam. We have a dealer south of us next to the freeway that carries Keystone Cougars. When driving past them in the right light you can see the waves in the wall from expansion in the heat.
I can't vouch for the Wildcat.

My 2nd TT had the same floating rear wall. Heartland North Trail.

It's just another way to save money by the MFG.
ppine
Explorer II
Mar 29, 2019
Sounds like water damage. If it is common the design is all wrong. Run away is exactly my feeling about a rig with spongy walls.

Forum Discussion

Exterior rear wall feels spongy

About Fifth Wheel Group

Related Content

Exterior Stairs

Spongy Floor

Spongy breaks

Spongy floor

Spongy Floor