While having my rig (Winnebago Aspect 2006 Ford 450)measured for levelers, the technician commented that my rear leaf springs were not "smiling" but "frowning and wavy" meaning to him they were dangerously fatiqued. When he called a company that supplied new springs they told him they thought Ford reversed the rear spings on the 450 sometime in the early 2000's. Anyone have any experience with leaf springs in this situation?