Sadly you wouldn't be the first with rcv issues.... at least they're good with warranty but too many guys seem to have this issue

Caster is tough to keep in spec on these vehicles. But as long as its positive and the vehicle tracks straight its nothing to worry about.

See if you can pull any codes with the superchips. All wheel speed sensors plugged back in (all the way in)?

You think getting in is an issue.... wait till you try getting that spare down! Lol