Never given caster a thought to be honest. So you don't think my wandering has anything to do with the tie rod roll slop?
Not sure, process of elimination though right. On my trucks clocking the tie rods helped lots, the latest UHMW disc between passenger tie rod post and steering knuckle tightened mine up on Tan truck such that I never (least not yet) had to clock the T rod ends.
Where I live due to heavy transport truck traffic on highways the road surface get longitudinal ridges in them and with wide tires and lots of side walls can lead to a wandering truck. So you’re constantly correcting the trajectory, now add that with not to spec U bolt torque on the front end OR rear end, non torque spec trac bar or mounting bolts, not enough caster, loose wheel bearings, bad tire or low tire pressure, tons of variables that can contribute to ****ty steering.
I will say the 37” Toyo R/Ts have been superior tires for sure, balanced well never a shake and so smooth, I will buy again for sure.
Just remembered I also install a Borgeson mid steering shaft, replaces the stock piece of keerap, between steering box and steering column.... there can be huge play there. If so short term fix is (while waiting for Borgeson) is tighten up the slide section of mid steering by using a chisel or air hammer and reshaping the groove to take out the rotary slop.
Cheers,
j