Well a lot of drivers do use air bags on their rear axles to give a better ride. A lot of Camper owners complain about the neck jerking when towing their 5th wheels. All I can think its the axle wrap that happens when the springs are not allowed to be fully loaded. Its much worst on 1/2 tons that have these bags, because the springs are weaker. After driving and towing for years I just explained this for the first time to a fellow Camper after realizing he had this problem. Its much better to have a full load on the springs because the trucks now have proportional loading that only load the plies as required. On my F250 I have 2 extra plies that does improve the load carrying capacity but do not improve the loaded ride. But I feel they do prevent the axle wrap when loaded. When I was towing with my 1/4 ton Ranger its was much worst and now I feel its the Axle Wrap that was happening. I guess its one more reason to have the right truck for towing requirements.