No "Return to Center" Steering Woes

[kberger]

Ok, I’m really getting frustrated trying to get my truck to return to center after a turn. I’ve done the “caster mod” documented many times on this site, moving my LCAs about 3/4” forward. Still no good. Today I finished installing new CPP UCAs that are supposed to provide 5 degrees of extra caster but still no good. The only thing that I can think of to do is put skinnier tires on the front. Right now, I’m running 275/60/15 tires all of the way around. Has anyone solved this problem while running wider tires? Here is what I’m working with:

1964 C-10, 350/TH350
1977 C-10 Spindles
Stock LCA with caster mod
New CPP 73-87 power steering box
Suspension is stock height