Does this frame cross-member break matter?

soren wrote:
Are several of the web rods in that truss snapped in half, as they appear to be? Might be interesting to get a Go Pro video of that area while the trailer is heading down the road. I'm guessing the whole mess is about as stiff as a bowl of spaghetti.

One member on here did exactly that. Wet spaghetti is what he found.

Are several of the web rods in that truss snapped in half, as they appear to be? Might be interesting to get a Go Pro video of that area while the trailer is heading down the road. I'm guessing the whole mess is about as stiff as a bowl of spaghetti.

Yes, photos please.

For the little I've seen, there's nothing I've seen that's holding the floor other than the frame rails.

I had the same thought at you about the floor holding the top of the rails in place - for far, I've found exactly ONE screw through the floor into the rails.

joebedford wrote:
Did you bolt in triangular gussets inside the frame?

No, when you think about it the current cross-members have little lateral strength and attaching gussets would be of little value.

Think about it this way; if you would work the spring hangers side to side with a very large adjustable wrench, that is what your suspension is doing.

When you mentioned the tabs on the top of the frame, you should have floor joists above the frame for support. The floor should give some help to the top of the I-beams and the added trusses will keep the bottom in location.

I have photos that I can link later if you want.

Did you bolt in triangular gussets inside the frame?

Lippert told me to weld in angle iron on the outside of the frame at each cross-member. The angles were to be installed with the tips of the iron against the vertical member and touching the top and bottom members. They said to stitch weld it. I chose to not do that as it would just hide any new cracks and it appeared to be of only marginal value. I welded the cracks and installed the hanger to hanger trusses. I made the parts to be bolted in so that repairs inside the belly cover would be possible. I now have no cracks after nearly ten times the distance that the cracks first developed.

Thanks for the cracked frame information. While my frame isn't cracked, it did confirm my speculation that the tabs on these cross braces should have been installed on top of the frame rails. I can see 4 of these cross brace ends and the tab is mashed underneath the frame rail.



From the Lippert repair instructions, you can see that the tabs should have been on top:



Because they're not on top, the floor of the RV is not supported by this cross brace and I believe it should be (there's about a 1/4" gap between the brace and the underside of the floor)

I think the answer to my question of what to do is to install gussets like #3 in the document above. Just HOW to do that is a bit of a problem.

This is my favorite coated 1/8" welding rod for repairing critically stressed parts. This is "magic" alloy. Light years stronger than 7018 and contains the metal vanadium. Used to be called "Super Missile Weld"


http://www.esabna.com/us/en/products/index.cfm?fuseaction=home.product&productCode=1135

Here is more information direct from Lippert:
Information

Cracks and problems are typically near spring hangers due to the high lateral forces which occur when turning. Each set of axles has a different turning radius around a turn and when making a sharp turn, like when turning a street corner or backing into a site, 2 of the 3 axles will get dragged across the ground. This forces the spring hangers to swing left/right and causes a lot of stress to the frame components and structure.

Is that maybe a floor joist? If so, the floor would be under-supported and possibly cause other problems above the floor level. Looks like a fatigue failure from repetitive high stress. Lippert frames are built the least substantial they can make them to save weight and $$ and who knows what a missing connection like that could do. Their welding can be substandard also. Is there anything else nearby that ties the two I-beams together? A piece of 2x2 tubing tying I-beams together is common and *if* there is nearby, at least the I-beams will be held together relative to each other. If the frame is indeed parallelogramming, it's not out of the question that there could be fatigue cracks in the vertical webs of the I-beams in the area around the spring hangers.

If it were me, I'd want to take down all the coroplast and inspect the entire frame. You might consider adding re-enforcement in some locations. Tying the spring hangers togther as mentioned by Lynnmor could help. It looks like that break has been there a while which could have over-stressed other areas of the frame? Not exactly the best time of the year having to deal with something like that but I would take care of it asap as mentioned above. If you were to take all the coroplast down, might be a good idea to take the trailer to a frame shop for an inspection and recommendations if needed, plus they can do the repair (and maybe in a better way than just re-attaching it like it was).

Good luck and it would be nice to see some after photos.