Theoretically it can only be 2 things. 1 being the toe. And 2 being that you lifted it and didn't install the radius arm drop brackets, but that only applies in 4wd.
You didn't say you were in 4x4 when it happens, so I'm gunna say that your toe is to far to the + side
Just have your alignment redone, and I recommend not going to the dealer for it, as usually the master techs who know the old TTB suspension are doing jobs that require thier skills, not simple alignments.
Funny thing is, is that the trick to doing the TTB alignment (other that knowing how it pivots) is to bounce the frontend after every little adjustment, and to absolutley make sure the pins are out of the slider plates, as they sould be with any alignment.