Cracks in siding above door

I have never ever seen anything like those cracks and I've had way too many trailers since 1988. Kinda looks serious. How do you crack aluminum?

We have a 2008 sunny brook that had the cracking above the door. Ours only cracked at the front radius corner. I took mine to the Indiana factory in 2011 to have it repaired. It was good until just last year when I noticed the same crack has developed again. I agree that the screws from the door frame initiate the crack and the flexing of the frame most likely during traveling causes it to propagate.
I drilled an arresting hole at the end of the crack and sealed it up. It seems to have stabilized for now

mosseater wrote:

bobndot wrote:
Even if the slide is on the opposite side of the cracks, anytime I have seen this happen is when people tried to level the TT once the slide was open.
You level it, stabilize it, then open the slide.

After reading one of the previous posts on this, I agree it's probably a weak spot in the build and that's where it cracked from the TT being stressed.

I won't disagree that the majority of trailers are nothing but varying degrees of junk, but if you look at most dealer lots, there are a lot of trailers with the slides deployed and no stabilizers down. I think if this were a root cause there would be a lot more cracks in siding than there are. Sunnybrook had a known issue and the OP has one of those units. The screw went into the siding and nothing else. That's his root cause. I've put my slide out without stabilizers many times since the repair without any negative effects.

I'm not debating what you said regarding this unit. :) I think my wording in my post might have been misunderstood.

It has nothing to do with not having stabilizers down and a slide deployed. That can be done without incident.

Its the motion of leveling an rv once the slide is deployed that can cause cracks.

bobndot wrote:
Even if the slide is on the opposite side of the cracks, anytime I have seen this happen is when people tried to level the TT once the slide was open.
You level it, stabilize it, then open the slide.

After reading one of the previous posts on this, I agree it's probably a weak spot in the build and that's where it cracked from the TT being stressed.

I won't disagree that the majority of trailers are nothing but varying degrees of junk, but if you look at most dealer lots, there are a lot of trailers with the slides deployed and no stabilizers down. I think if this were a root cause there would be a lot more cracks in siding than there are. Sunnybrook had a known issue and the OP has one of those units. The screw went into the siding and nothing else. That's his root cause. I've put my slide out without stabilizers many times since the repair without any negative effects.

Even if the slide is on the opposite side of the cracks, anytime I have seen this happen is when people tried to level the TT once the slide was open.
You level it, stabilize it, then open the slide.

After reading one of the previous posts on this, I agree it's probably a weak spot in the build and that's where it cracked from the TT being stressed.

Our 2008 Sunset Creek 298 BH, and many others, had the same issue. Sunnybrook fixed quite a few of these as warranty issues before Winnebago took over. You had to take the trailer out to their facility but they fixed ours no charge. The issue is lack of support above the door frame, and the screws for the door frame go into the siding only and don't make contact with anything else. They installed an aluminum panel above the door and then screwed a new piece of siding into the panel. Ours was repaired about 5 years ago and has shown no sign of cracking since. You can call them and see what they say about it, but I doubt they'll fix it anymore. They had quite a few with the same issue and I think it really hurt them in the pocketbook.

Thanks everyone for the feedback and advice about always using the stabalizers. I'll be checking the frame where I can.

I had exactly the same issue with my camper; Mine was caused by the frame flexing
slightly and causing stess at the top of the door; I'm guessing that your door sticks sometimes;

I never fixed the problem but I did the following to stop it from gettong worse;
1 - always put the stabilizer down before opening the door and entering/exiting
2 - never move the camper with the door open
3 - when in storage, put down the stabilizer

Hope this helps

My guess is that those are possibly being caused by a frame failure or frame flexing. Frame failure caused by broken welds. Frame flexing caused by jacking up the trailer improperly or from over-tightening the stabilizer jacks.

Crawl underneath and look for frame cracks or broken welds...
Good luck with it.

I have several stress cracks on the Filon siding for my 1994 5th wheel.

Two continually expand and I have to fill them with eternabond caulk every couple of years.

One of these days I intend to clean up the cracks and shave the cracks to make a V shaped groove along the crack and then squirt some adhesive in between the siding and the luan to make sure there is a good bond. Once that dries then I plan to use "Bondo Hair" to fill the cracks, sand smooth and paint. Bondo Hair is Bondo with fiberglas hairs in it so it helps to fill gaps.