A question regarding BIGFOOT levelers, I have always powered up, hit auto, STEPPED BACK, and watched it do its thing.All four feet always came down and made ground contact. Today i decided to retract, and reset, the fronts came down about 5 inches, and stopped, the backs came all the way down, made ground contact, and did there thing. Is it normal to have only the fronts down, or only the backs down? Thanks Gene