TrailManor 2720 SL torsion bar bracket pulled from rotted subfloor

[jbrowner84]

Hey TM Owners,

First post here! I’m hoping to tap into your collective wisdom regarding a serious issue with the lift system on my 2003 TrailManor 2720 SL.

The 4 main bolts under the entry door/step—which secure the tension bar to the subfloor—have completely pulled out of the structure. The driver’s side is starting to do the same.

I ran an endoscope up into the bore holes, and the scope confirmed that the internal substrate is stripped, rotted, and deteriorated. There is simply no material left for the threads to grab, allowing the massive force of the torsion bars to yank the hardware right out. (Scope photos attached).

My Thought / Proposed Fix:I am considering injecting a heavy-duty, high-strength injectable wood filler directly into the wallowed-out holes to pack them solid, letting it fully cure, and re-drilling.

I’ve searched the archives and seen a few threads on this, but the common advice seems to just be tightening the bolts or using larger ones. Given the rot I’m seeing on the scope, larger hardware feels like a temporary bandaid.

Before I proceed, I’m looking for some advice:

1. Has anyone successfully used an injectable wood filler to repair these high-stress anchor points, or will the torque of the torsion bars just crush the filler over time?
2. If wood filler isn't the right permanent fix, what is? Either stabilize bolts by opening the floor and using steel bracket on the top of the floor, or have a channel bracket run along the subfloor to the step or subframe.

I want to fix this safely and permanently so the lift mechanism stays secure. Any advice or guidance would be incredibly helpful!

Thanks in advance.

 

[Bill]

Have you found this discussion?

https://www.trailmanorowners.com/threads/arm-mechanism-missing-bolts-to-body.2195097

Your picture shows that in this area, your TM was assembled using machine-screw bolts (big threaded screws that mate with a hex nut or similar fastener), rather than a lag bolt (big wood screws that bite into the wood with no separate fastener). TM did it both ways, with the machine screw being later. Given that this is the case, filling the hole with wood filler and drilling it out, in an attempt to provide something for the threads to bite into, probably won't work since the threads aren't intended to bite into anything. Perhaps you could remove the machine-screw bolts and substitute lag bolts, but since the compression strength of the base of the wall is gone, I'm not sure that the hardened plug wouldn't rotate as you try to thread it, or pull right out under the stress.

When this happened to me, I was lucky. There was no rot - the machine-screw bolts had simply backed out of the T-nut. I pushed the bolts back in and tightened them, and all was well. Since you have extensive rot, my thought is that you need to remove and replace the rotted wood in the base of the wall, to restore the strength of the wall and provide something for the bolts to attach to. I have not done this, but it would seem to require opening an area of the inside wall, right down at floor level, to get access to the rotted section. Not a pleasant job, but I have not seen an alternative. I think Melissa had the right approach in Post #3 in the linked thread.

 

[jbrowner84]

That’s a great find — it looks like the exact issue I’m dealing with. I’ve had some success using wood hardeners, but I haven’t done much repair work on enlarged or damaged lag‑bolt holes. The thread you shared is especially helpful because it shows what’s actually between the layers of the subfloor.

For clarity, in my photos the two parallel threaded “bolts” are actually the gas lines. Because of that, I’d prefer to keep the repair as minimally invasive as possible. If I can avoid removing and replacing the entire section of wood, I’d much rather focus on filling and reinforcing the existing holes. I'll continue with updating this thread as my repair progresses.