Well, he went ahead and traded elsewhere, so for now, I'm not going to be able to look at this truck...However, I'm going to next week get a new one and hook up to a "like" trailer and see what I can find...spoke to another dealership and they had a truck that did the same thing with this type of bumper pull camping trailer.
PS to Hydro, yes he had tried a "equalizer" hitch as well as a new "4" point hitch to try to correct....