wolfe10, thank you for making that more clear, you're right it absolutely did make a harsher ride. I would not use the SL's unless I was running at a max gross situation as I was.
My rig didn't feel so hard at max. It didn't pound like it did running light, that was too hard a ride. That was the nice part of the adjustable SL's , it allowed the normal OEM spring rate when not needed. Just swing the SL's out of the way as I did. I think there are two models of SL's stationary and adjustable. I would only install the latter.
I wonder if the OP's floorplan has a drivers side full slide, making the rig off balance to begin with ? like the 31G.
If that's the case, then maybe a set of air bags with individual lines to level it side to side would offer a better fix.
I would get a scaled weight to see how close you are to gross weight all loaded up as well as right to left weights.