Hello, I wanted to share how we have replaced the crappy old axel on our Caravel
with one supplied by Inland RV.
The original design shown below had the dampers orientated near vertical, connected at the top to pivots at the end of metal brackets which were welded to the axel and bolted to the chassis.
We cut off the damper brackets from the 1961
rust treated them ...
bolted them back to the chassis place where they had started and installed the new axel under them (drilled 2 holes each side through the lower flange of the chassis' channel, bolting it in place with 4x 1/2" fine pitch nuts and bolts).
THEN as we were happily jumping up and down on the chassis in celebration of the awesome job we'd done, we noticed that the geometry of the new axel with the old bracket wasn't translating ANY suspension travel movement into extension of compression of the damper (see how the dampers are not vertical now?). The damper was orthogonal to the arc of the suspension travel. This is because the damper pivot point on the new axel is in a totally different place than on the old one.
Back to the drawing board.
If you look at how the damper is intended to be used with the new style of axel (see next image of someone else's more modern trailer), you'll see that the damper points forward and down, so that its axis is tangential to the arc that the DuraTorque style suspension travels in. This means suspension travel directly compresses the damper, approximately 1:1. (note in this image I think the damper is installed upside down ... don't want water collecting in the cylinder, right?).
So we fixed it by designing a custom 1/4 inch steel plate to replace the 1961
brackets which put the damper pivot in the correct place for 1:1 geometry. We bought axel studs from Inland RV and welded them on. Here's the final result. Looks nice right?
We ended up with 2x5/8" bolts connecting the plate to the chassis, 2x1/2" connecting the plate to the axel's vertical flange, and 2 1/2" bolts connecting the chassis to the axel's horizontal flange. Pretty sure it's not going to fall of anytime soon.
Anyway, hope that's useful for someone out there! Chris.