this is how I approach these problems.

l1)check tire pressure first.run them on the higher end,low tire pressure can cause this on trucks.( ford even has a tech. service bulletin for it)
2)tire balance-make sure a tire doesn't have any wobble.put the best 2 up front. I have also seen certain brand of tires 1/2 worn cause this.
3) inspect front end for play. replace any worn parts.
4) have alignment checked. keep caster in spec. Do not set higher,high caster can cause wobble.(e.g.) push a shopping cart a little too fast,front wheels start going nuts(we've all done this)
5)installing extra parts that didn't come on the vehicle might make the problem go away (for a while) that is only masking the real problem.
<<<<if the track-bar is solid,(most common front end component cause) and the rest off the front end is good.most of the time it is a tire issue.
For independent suspension: jack up suspension as close to the tires as possible,That unloads the ball joints to get a better feel,use a big bar and lift up on the tire to check lower ball joints better. Solid axle is not critical that way.just jack it up.still uses a bar though when the lower ball joint faces down.grasp the tire at 12 o'clock-6 o'clock,/11-5 ish for ball joint check.push and pull with some effort.