The other problem that can occur when loaded at 2500# with 70 psi in the bags is when you lower your landing gear without bleeding off some air from the bags, they will exceed 100# immediately.
My air bags are set at 10psi empty. After I hook up my 5er and lift the landing gear, my bags will be...
Seems a little high too me. Firestone recommends 5-10psi empty. My 5er has around 2500# pin weight and I run 45-50psi loaded.
I determined this by measuring the height of the rear bumper unloaded, then hook up trailer, lift landing gear then inflate bags up to the same measurement. On my 5er...
I currently have a Western Uni-Mount 8' Pro-Plow and have owned many other models over the past 23 years. I have never had to use ballast and for light snow, I plow in 4 hi. When the snow is wet or deep, I plow in 4 lo.
The plow truck at work has a 4x8 piece of 3/8" steel in the bed.