I don't have any direct experience with caster adjustments, but this is my understanding of the E350, E450 and F53 chassis:
The more caster you add, the more return to center force you have. Ford specifies a caster of something like 0 to + 5 degrees of caster. If you want more return to center force, and most do, have it adjusted to +5 degrees, maybe a little more or less left to right for normally cambered roads. Your alignment tech should know about this.
Excessive caster will result in tire wear, but +5 degrees is not excessive and any moderate tire wear is offset by better steering.
Another way to add return to center force is with springs, like Roadmaster. But I would prefer that suspension geometry do it, not springs.
David
David
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