Not sure upper stableloads are right for me (UPDATED)

You want the StableLoad pads to engage the upper spring with the camper loaded. This is what gives you additional stability and less sag. If your camper is so light, that the upper overload spring has no deflection, you actually need a taller pad than your current StableLoad. The lower StableLoad wedges will do less for sag but will engage the main spring pack earlier giving you less sway (this may be why you see some references to installing this product first).