Queer Steer
#3
The stock steering shafts are sloppy. I've put a Borgeson shaft on 3 of my trucks and they're a lot tighter. Make sure your tie rod ends and draglink sre tight. Worn kingpins, spring bushings, and front spring hangers will give some steering play too. Also the adapter plate that bolts the steering box to the frame is famous for cracking.
#4