Check the mount points for the trac bar. The tie rod looking bar that runs from the frame to the axle to keep it centered. They're notorious for hogging out the mounting holes allowing the axle to shift side to side as you turn.
"But it does me no injury for my neighbour to say there are twenty gods, or no god. It neither picks my pocket nor breaks my leg." - Thomas Jefferson, Notes on the State of Virginia, 1782
Arguing with a truck driver is like wrestling with a pig in mud, eventually you realize the pig enjoys it.