Hard to say if it's caused by a weak spring or shock but I'd guess a bad shock. Remove a shock or two nearest to where you notice the problem the most and push-pull on them to see if the shocks significantly resist movement equally in both directions. A good shock will, a bad/blown shock will be relatively easy to push in and pull apart. No need to jack the Jeep up or remove tires to remove/replace shocks.I too have RC shocks and springs and notice that when I hit a large dip, my jeep will swing low, sometimes rubbing the fender flares. Will the RS5000X lessen that drop? I'm also on 2.5 RC springs. I was thinking Savvy 3" progressives might help too.