[Mikendebbie]

Since your unit has a "rear wall" rather than a "rear cap" - my question is how do they attach walls to the frame and to each other at the corners? - because your connections have obviously failed or have come loose.

I have watched several factory tour videos of the Montana factory in Goshen, IN, and I do not remember ever seeing a close-up of exactly how the walls are anchored. They show several shots of the walls being moved into place on the frame with an overhead crane. I assume that maybe they build the laminated wall units and provide some number of "leave-outs" at the base and along the corners for intersections to be bolted together. I don't know if they use self-tapping screws or if they use bolts, nuts and washers. The walls are not "built in place" like the walls in your S&B. They are built in a separate area of the factory then moved to a different location for assembly onto the frame. Maybe someone on this forum can help you find the anchor points. If you posted the question to the Montana Owners Forum , lots of those folks have been on the factory tour and maybe someone there could advise you how the walls are anchored and what to do next.