After fighting the factory air suspension for a year I decided to upgrade to the Bilstein shock/strut setup.
That left me with no rear air setup that I really like for connecting to a trailer. After looking at ALL the aftermarket options I decided to build my own. The reasons I went for my own design are: wanted to be able to drop the rear at least 2" lower than stock for connecting to a trailer and raise the rear 2" higher than stock for a bit of lifted look.
Most kits gave me the ability to lower OR raise but not both. I started with a pair of 2" lowering rear springs so the truck would sit lower with no air for connecting to a trailer. Then made brackets to support the new Firestone 9002 air bags which will give me 2200lbs of load capacity.
I used these same bags on my Cummins Dakota and they worked fantastic, I also put 4 of them under the back of my RAM 3500 deck truck for dropping the back of the deck for loading.