I saw a Dodge 3500 with a rear air bag which was located at the rear of the springs, not over the axle. I spoke with the owner who tows a 5th and he said it was the smoothest ride with or without the trailer he ever had. He stood on the bumper and jumped up/down to show how much it moved with just his weight (~175# from poor guesser).
I don't remember the manufacturer and probably won't ever see the guy again. I've spent lots of time DAGS with no luck.
Anybody know of any setup like this?
FMB (North Mexico)