Chevy 1500 rear leaves. I am running shocks made for a 4x4 F-350 w/ 8" lift. IDK why but those were the only shocks I could find that were the right length. The shocks for a 6" lift 4x4 Ranger I got were way to short (they were only like 1" longer than my stockers ???), so I called Tuff Country and had them look up shocks by dimension. But in reality shocks have no effect on how much weight your truck can handle. They simply dampen the release of energy from the springs to reduce bounce, they dont support any weight.
My truck normally has a little rake to it anyway, I would say it was squatting about 2-3" in the rear. A Bobcat S-130 (w/ no bucket) weights 5,235-lb (2375-kg), and the trailer is a HD homemade beast probably weighs 1200lb.lol