I would like to install air-bag type load levelers on the rear of my 2000 3500 4wd. When I use my slide in camper the truck drops about 5" and the steering seems a little light. The two questions I have are 1: Will they affect the ride height when empty and 2: what brand is the best. I have looked at Air Lift and Firestone Ride-Rite. Can anyone give an opinion?