Ford Expedition Mechanical Rear Load-Leveling Suspension

Had a Expe. It had the air ride leveling system. You still have to use a WDH. And if it is still air operated. The instructions went like this.
Take it, and the TT somewhere level. Unhook the TT. Let the Expe level itself. Turn off the leveling system. BEFORE it has time to lower itself. Lower the TT back onto the ball. Then adjust the hitch as normal. After youe are done. Turn the system back on. You never need to turn it off again.