Although I like the Timbrens that I am currently using, they won't help you level side-to-side. For that, you need air bags.
If I am reading your post correctly, you have a 10.r foot camper on a dually and your mud flats are dragging.
If this is true, you have a significant problem, poor springs, missing or weak overload springs, wrong air bags, or poorly installed air bags, or????????
You should have a spring shop look at your suspension. Something is seriously wrong. Get a free quote or two. Don't spend any more money until you know what is wrong.