Random but violent front end vibration

I would do what I've ALWAYS DONE, and just did a couple weeks ago with my 2-4WD converted Cummins. Get a friend, or in my case I used an old video cam wired to a monitor---to closely look at EVERY thing under there that moves and or IS NOT SUPPOSED TO MOVE

Start at top and work your way down.
1..Determine FOR CERTAIN that there is NO PLAY from the steering wheel to the steering coupler. Then wiggle the wheel and..........
2...Look at the joint between the column, the coupler, and the shaft into the box. Look for ANY differential movement when wiggling the wheel.
3...Next watch the shaft into the box and the pitman shaft. Look for rotation, up and down, and side to side play. Move to the tapered joint at the pitman shaft, look there

4....Look at all 4 tie rod ends, look for play

5...Look for play up and down and bearing side play, and tapered end play in the idler arm

6...If you do not have, go to MyMopar.com and download a service manual, for free. Look in there for PROPER bearing adjustment, not just tighten them up

7...Also in the manual is procedure for checking ball joints. Lower arms MUST be supported ON the ARMS to check lower balls.

8....Obviously, also look at upper arm bushings. LCA bushing is tricky, so look that over REALLY good. Strut rods can be tough to check as well crowbar, etc may be needed.

9...STEERING BOX!!!! They can come loose at the box to K mounting bolts!!! Look CAREFULLY for ANY box movement.

10... You might spin the wheels and check runout, for bent rims or other problems. Other than the wheels, "the usual" bad tires, internal tire damage, balance, etc. Might consider trying different front wheels / tires

11... Check disc rotor runout.