What little bit I know of the chucking issue is that it seems that the "mating" of one's fifth wheel hitch with one's pin box is the issue. I suppose new shocks might help with that, but I don't know for sure.
A couple of links to maybe help you.
E-trailer Site Explanation of Chucking
Lippert Article on Chucking
At that Lippert article, I noticed that they showed a TrailAir pin box. We have a Ford F450 and a Mobile Suites 38-foot fifth wheel with the TrailAir suspension and TrailAir pin box with Tri-Glide. The Tri-Glide was/is touted to be beneficial for reducing chucking. It may be a good thing as we seldom ever have an issue with chucking. The only time we had a bad issue was on an Oklahoma freeway (turnpike) where they didn't build their elevated sections very well. Those transitions from one section to another really caused violent chucking, enough so that we had to slow down to 45 miles per hour to eliminate it.
Terry