For discussion purposes
DPelletier:
I did find the air bags added a lot of stability on my 00 2500. Having separate fill valves and adding about 80 lbs of air to each bag had a tremendous stabilizing effect on it. I had 3200 lbs of pin weight from my 5th wheel.
If you have a single fill, the air actually shifts from one bag to the other, which seems to match the experience you are reporting about stability. Also, on a dual air fill setup, as the amount of air is increased in the airbags, so does the amount of increased stability that they provide.
In fairness, though, I have to also report that when I was removing all the accessories from that truck, I found that the bottom rear bolts of the upper mounting brackets had sheared.
So, that tells me that, although I had great handling with the air bags, that I could have had a serious failure under heavy load in a curve.
Everyone has their own experiences and these are mine.
Wiredawg