worn out leafs?

Shocks arent designed to hold up car. Springs are. Apparently previous owner knew springs were weak, and put air shocks on it. They will raise the vehicle, but if you use them to lift/support weight of vehicle, eventually you will be replacing not only the springs but also shock mounts and different shocks too.
(Kinda like Mr GoodWrench commercial, you can pay me now, or you can pay me later.)