Club91: As others have said, welcome.
We have the LM 365 Key West and a Ford F450 and we also seem to feel more chucking. We did exchange our MorRyde hitch for a TrailAire with the airbag and the quad-pivot king-pin (older assembly than their newer model but one I was familiar with). That said, we had a shorter coach that was traded in and we experienced some chucking with it as well. That we attributed to the length of the truck and coach being the right (???) length to extenuate the effect of the concrete cuts on our ride. Now, with the LM being almost seven feet longer, I think we just traded one that met that length to another one :angel:
Of course our deteriorating roads don't help much when they patch them with what appear to be rail-road ties between the concrete slabs (at least here in Kansas - I don't know what they use to level the concrete patches but it sure isn't working LOL ). Then we also add the fact that our KW is 4K heavier than our old coach so we have more back there pushing / pulling on us when we go over those things.
On our Key West it seems to be much worse when the coach is light (no water in the fresh water tank). That leads me to believe that hitch king-pin weight might also be a factor. I mentioned this to a local Keystone dealer who suggested that I get a pin weight both with an empty fresh water tank, and then with what I would normally travel with plus clothing, etc. As I recall we should have 20 to 25 percent of our weight on the pin. I have yet to do that but we recently came back from a trip to New Mexico where we did travel with water about half full, plus food and clothing, and I'd swear that the chucking was much less. Sorry I can't be of more help - I also suggest you check the water/pin weight theory though. Let us know what you find out.