Our Radflos Work Well
I noted up thread that some were having problems with RadFlo/EC shocks. We mounted ours back in May and have run them through the summer without any problems and we're very happy with them. I have seen one set on another truck that leaked in front, and I suspect the leakage was caused by the fitting on the upper shock body for the remote reservoir hose coming in contact with a lip on the Fuso's upper shock mount.
When I mounted my fronts, I spent considerable time figuring out what position of the upper body would provide the best clearance for that fitting. I think it is important to do any rotating of the upper shock body only when the threaded stud is completely free to rotate. I think that is important so that it is the complete structure of the shock that rotates and not the upper body independently of the threaded stud. I'm not sure, but I suspect that rotating the upper body with the threaded stud fixed could contribute to leaking at the top of the shock. When I examined one of the shocks that had been leaking on the truck of a colleague that looked like a potential source.
In the other situation mentioned above, when the hose fitting could contact the Fuso shock mount, that wouldn't happen ideally. However, if the nut on the threaded stud is not tightened enough, or is over tightened, then the rubber cushions that are part of the shock's mounting hardware may distort and facilitate contact of the fitting and the lip. If the fitting contacts the lip, then the fitting could be pushed out of alignment and allow fluid to leak out around the seals of the fitting. If you want check for contact, I'd look at the fitting and the lip for signs of pushed metal. If you see that, I'd hypothesize that you've had contact.
If you were worried about potential contact, there are a couple of things I think I would try. One would be removing a bit of material from the lip on the Fuso mount. The lip has a horizontal step in it, and it looks to me like removing the lowest portion of that step would provide some additional clearance to avoid contact. Another possibility would be to install your front shocks with a third metal cup washer. The normal install is shock > upward facing cup washer (#1) > rubber cushion (A) > Fuso shock mount > Rubber cushion (B) > downward facing cup washer (#2) > nut. Placing an additional upward facing cup washer (#3) between #1 and the first rubber cushion (A) might act as a spacer that could move the upper body of the shock down and provide more space between the fitting and the shock mount. In turn that could allow for more distortion of the rubber cushion without contact.
While I thought of doing either or both of those after I saw the truck with the leaking from shocks, I decided to leave our installation alone. I do monitor the apparent position of the fittings on our front RadFlos relative to the lip on the Fuso shock mount. So far I haven't seen any movement and we have no leaking. That could be dumb luck (a good hypothesis in my case) or the result of careful installation / monitoring. The only thing I'm sure did not contribute to our lack of problems is treating the truck to easy tracks. This summer we've traversed some of the roughest country yet in Prima Terra (our EarthCruiser).
For us, the shocks work great, provide a comfortable ride, reduce swaying on poor surfaced shelf tracks, handle washboards well (with appropriate tire pressure) and we'd buy them again. If I was concerned about attempting the potential solutions mentioned above, I would contact RadFlo or EC & get their feedback.
Howard