Yes, that is much worse than what I am seeing with ours. I have a welder and some angle iron. I am thinking of making an outrigger or two and bolting it to the frame at the front and back of the slide-out. I will see if I can use a jack to raise the side back up first though. Another alternative is to visit a metal shop near me and see if I can get outriggers made and welded to the frame. That would likely be better, but bolting them to the frame would probably work also.

+1 to mjlrpod. I wouldn't try to through bolt to the 0.1 inch frame tube. If you want to attach to the frame without welding to it, then I'd suggest following the procedure that FR did fixing the floor in the video. Weld plates to the supports and TEK screw them to the frame. 

Thanks. I got my repair completed and posted details in my mods (link in signature). I don't think the welds broke yet as the floor did not seem to be too far off. The outrigger supports I made are to make sure that the floor does not sag too much which would stress the welds even more. We need to make a trip though so I can see if they are working as expected.

Originally posted by Andy I was concerned about this with our 179 and contacted FR who recommended the outriggers.  They made it sound like it might be some type of post production warranty as they said if I took it to the dealer and it was a problem then they would send the outriggers to the dealer who would install them.  I hope your dealer is way better than ours! Fortunately things have stabilized and I've not had to do that.