We run 3.5 tonne tippers with arb bodies (high sided ‘gypsy wagons’, but old and not shiny…) with uprated springs as they are more often than not running fully loaded.
They usually tow 2 tonne tracked chippers on plant trailers, which are relatively nose-heavy when loaded (I’ve not actually measured the nose weight, but they tow fine on the various vans as well as pickups and Land Rovers, so they aren’t miles out weight-wise).
The nature of what we do means that the hitch height can change several times during a working day, so we don’t bother with adjustable hitches. When the vans are empty the nose weight is arguably too heavy, but we have never had any issues over tens of thousands of miles.
The Ifor Williams GH plant trailers have been consistently the strongest we have used, and the standard ribbed jockey wheel setup fairs well (unless dragged down the road…).
The Brian James trailer sadly didn’t stand up to the way we use them, but it might be that we are too rough (and need kit designed to survive Welsh hill farmer’s demands!).