I had posted this over in the TT & 5ver Section but since it involved my Everest thought I would post it here as well.
While backing my 5ver I heard a loud noise and noticed the trailer was leaning abnormally to the left and the tires were touching in the middle.
A quick inspection revealed that both metal hangers that connects the rear spring to the equalizer had broken at the bolt holes and the rear spring had impacted with the trailer frame.
After removing the springs and equalizer I discovered that the bolts were scored badly where they fit into the metal hangers, the bushings seemed to be cheap plastic instead of nylon and were worn out and cracked in half, and the bolt hols in the hangers and the equalizer were wallowed out on both sides of the trailer.
I temporarily replaced the worn suspension components (bolts, bushings, and hangers, using bronze bushings in the equalizer to overcome the slop of the wallowed out bolt holes and nylon bushings elsewhere.
I ordered new equalizers, bolts with grease fittings, and bronze bushings for the entire system and will install them as soon as they arrive.
If you own a Keystone product, I would recommend you inspect your suspension components for excess wear. Left unattended it could result in a major suspension failure.