I know this is a controversial topic: Steering stabilizers!
My truck likes to swim around a bit at 30 - 40 mph and I have some slop in the steering, despite newish kingpins, new bushings on the front leaf eyes. I played with tire pressure, and the front end is set up properly... the steering on these trucks is not precise.
Years ago I put in a saginaw box with cross steer, as I use it as a daily driver in the summers. My worry with this modification was framerail flex in the steering. I bolstered the heck out of the driver's side frame rail, and made some progress, but ultimately it still flexed, which also led to sloppiness.
I bought a steering stabililizer from LMC truck and installed it yesterday.
All I can say is wow. The axle is now tied to the tie rod tube with a large shock, which tucks up behind the axle. Not only does the truck steer much more precisely but the stabilizer seems to oppose the twist exerted by the pitman arm on the frame. Sounds goofy, but now I have nice quiet steering, no belt chatter.
I know that some call this a band-aid, but this is a major improvement!
Good weekend.
Next up for this winter is to fabricate a front panhard bar.