I've been having the same issue for some time now with my 2018 Power Wagon. Low speeds, under 40, going over bumps I get a feel and sound coming from under the front like something is loose... can even feel it in the front floor, under my feet.
Dealer found no issues anywhere in the front suspension or steering. I have a t\Thuren level kit and brand new shocks. I replaced the OEM parts - the drag link (Thuren), tie rod (Synergy) and track bar (Thuren). All are torqued and re-torqued properly per the installation instructions.
Seemed better for a short bit, but still get the same issue. I did notice that, when running but in park, if I turn my steering wheel just slightly from side to side, I get a clicking from under the front end - doesn't feel to be in the column inside the truck, but under it, outside of the cab. Wondering if it's a U-joint in the mid shaft of the steering column?
Frustrating enough that I am considering a trade. But I will be out under the truck again this week trying to see what I can find.