48Rob wrote:KC, You're saying that travel trailer, cargo trailer, utility trailer, and flatbed trailer manufacturers are producing thousands and thousands of units each year with incorrectly installed spring hangers?
At first glance, it does look like a stronger method of attachment, but I'm not an engineer.
Why do you think they don't do it the way you believe is correct?
Rob
Why? Ignorance.
Plus Dexter, the predominant axle manufacturer in the US does not spell this out in any of their obvious literature or online tech support (at least I couldn't find it).
I was in this boat, too, until I worked at Giant-Vac (now defunct) and saw it done the correct way. As an engineer, once I saw it done the right way, it just clicked and made sense.
Not every OEM bothers to study the equipment supplier's spec.'s, and even if they do this info rarely makes it to the production level where the "weld bead meets the road", so to speak. Even if they started out doing it correctly, when the next guy comes along and doesn't get fully trained before they put a MIG gun in his hand things can go sideways and stay that way because, "that's the way it has always been done".
Just because something has been built by a "professional" doesn't mean that it was done correctly. It just means that they got paid to do it! Call me a cynic, but it's true.

Here is the link to the etrailer info
http://www.etrailer.com/question-15711.htmlEdit: I see now that you both beat me to the punch.