My dump trailer is a single cylinder, scissor style, power up & down. It is the typical 9995# rating to keep it under the 10k limit requiring additional licensing and registering issues. It was also fitting capacity for the truck I had at the time when I bought it. The load capacity is about 6700# as the trailer is almost 3300#. I typically shoot for 3.5 ton max load weight regardless of volume in the bed, which typically leaves plenty of empty space. That being said, even when being loaded within the weight range, distribution of the load is just as important. I have had places wanting to load the front heavy with the intention of more tongue weight for stability, but I had to explain that with a dump trailer too much weight in the front just makes it more difficult to begin the lift for dumping. Of course you need to manage tongue weight correctly but wisely with a dump trailer also, or you will have trouble lifting. I have had mine overloaded before by weight and whether or not it lifted it all depended on load distribution.
I have hauled MANY loads of fill dirt and some contained a good bit of clay which would sometimes stick to the bed and would not dump well at all, regardless of weight. I came up with a trick to always have a successful and clean unloading, but I won't get into that here. I also had a very full load of mulch recently that did not dump very well either. What I have found is that once you have a dump trailer, it is used for all kinds of materials, items, etc., well beyond anything you would have thought of before buying one. I'm just saying never say never, LOL.
I have hauled MANY loads of fill dirt and some contained a good bit of clay which would sometimes stick to the bed and would not dump well at all, regardless of weight. I came up with a trick to always have a successful and clean unloading, but I won't get into that here. I also had a very full load of mulch recently that did not dump very well either. What I have found is that once you have a dump trailer, it is used for all kinds of materials, items, etc., well beyond anything you would have thought of before buying one. I'm just saying never say never, LOL.