My 2500HD started sagging when I bought my new 5er, My old one was almost 400 lbs less hitch weight. I was looking into air bags but I was not quite sure i was not convinced as to everyone that has had them that I know around here say they started leaking within the first year or 2. After doing much research I have decided to go with the Roadmaster Active Suspension Roadmaster Active Suspension Kits | Helper Springs | Overload Springs
I think this will help with my problem, there is a review on youtube Roadmaster Active Suspension Systems - YouTube
and check it out before you make your decision. I found them for 315.00 including shipping. i hope this helps.
Scott & Vicki
2015 Silverado 3500HD 6.6L Duramax/Allison
2013 Columbus 295RL
Camped 2013 110, 2014 129, 2015 97
2016, Camped 69 nights, 25 Nights Reserved