Storing Truck camper

First thing avoid taking the camper off the truck with full tanks.
I was not the only one who observe floor separation while having the thing hanging on the jacks.
Now I support front of the camper with block of wood and 4x6. Not only hold front floor, where water tank is, but also keeps it steady.

I stored mine on just the jacks for several years. It weighs about 3,500 pounds. But, we use it a fair amount at home. We use it as a guest suite, extra food storage, hiding from the kids, etc. So, I made a wooden prop for the front. This helps take some weight of the front jacks but mainly it takes out the sway and shake from waking around in it on the jacks.
Torklift makes a product called the Wobble Stopper. They do the same thing as my wooden prop and look better doing it. Also, their easier to store and transport. I have some and use them when I use the camper off the truck out camping. They make it solid as a rock when used off the truck. But, they don't take any weight off the jacks.
So, at home, I still use the wooden prop.

I always used blocks under it, but was told by a family member thtvhad a newer one, you don't need to. I was always under the line of thinking, that I wanted my floor supported.