Steering "wiggle" on gravel/rock roads

I'm in Death Valley right now - the truck's steering is perfectly smooth on the asphalt, but gets a good shake going on the gravel/rock roads. I expect the steering to move, but it seems there must be a way to smooth it out. New rack bushings? What else?

 

Check your ball joints tie rod ends ect if these get sloppy it can do what you've described make sure steering box is tight on the frame hope this helps.

 

There's also a slip joint on the steering column that goes to shit and needs to be welded up if you find everything else to be in order

 

I'm back home now and will give these things a good going over - thx for the pointers. . .