Could be ball joints or tie rod ends.
Check your ball joints - Lift the truck so the tire is off the ground. Grab the bottom of the tire. Pull toward you and push away from you. If you get movement, it's probably ball joints.
I was getting my tires rotated and the guy comes in and says, "I've got something to show you." This can't be good. Nope, it wasn't. The tire was moving in and out about 1/2". I had been getting a pop. A few days later, the truck was in getting the upper/lower right ball joints done. The left side wasn't doing it.
Just a suggestion.