Hello Randy, are you saying that your trailer has flipped over every now and then using the CJ leaf springs? I don't want this to happen even once if it's the case...I've seen one of my wheels pop up after hitting a large rock, and I was off camber at the time...
Well, I must confess that the Packmule has only turned over on the Dusy/Ershim trail. An extreme 4-wheelin trail from kaiser pass to courtright reservoir in the Sierra national forest, 35 miles long, John Muir wilderness to the east and Dinkey lakes wilderness to he west, mostly at 9500' elevation. Very few 4-wheelers chance pulling a trailer over that trail.
Since I added the axle limit straps and bump stops, and went back to 37" tires (I ran 40's for a while to match the jeep), I only turned it over twice. Once dropping down into LakeCamp camp, an extremely rocky route where I was not able to choose a good line for the trailer. When the jeep dropped down off a large rock in the back, the trailer short cutter the route and went over on its top. The second time I was not paying attention and put the trailer on its side leaning up against a tree. Did not go all the way over because of the tree. The X-O skeleton roll cage I built around the trailer saved the roof top tent both times. No damage to the trailer or tent.
On graded (some neglected, not graded recently) forest service, mining and old two track routes, I have never turned it over. So if you pay attention to the trailer, travel on reasonable routes, you should not turn a trailer over.
The CJ springs have an extra leaf, military wrap style, and maybe even an add a leaf. The trailer is heavy, about 1500# if I remember right (should weigh it again loaded, with 18 gallons of water, 10 gallons of gas). The CJ springs give the trailer a much softer ride than the short trailer springs. I have broken many trailer spring main leafs, they were just not up to the beating the trailer gives them. The trailer axle has shock absorbers also.