Thanks for the replies.
The tires are all new Michelins, bushings and other components have been checked by Liberty, alignment and tire shaving were done when the tires were installed (10 days ago) and again today (I will drive it again Sunday). I have to be in Jacksonville later in the month and will have Prevost check it out if it persists.
It could be that I'm being too concerned over what may be a normal thing, but don't think so.