I once owned a balancing business for aircraft engines and propellor's and did thousands. The system for wheels/tires operates the same in concept and identical in measuring. The system measures in inch's per second of movement or IPS. If the balancing system says you have .000 movement then you have none and that's a perfect balance. The scale goes from .000 to 1.00(one inch per second) or worse which is a lot of movement. If it we're me, I would have them pull the wheel and check it by itself. If it's within limits then put the tire on and see what it does. If it skews it way off then the tire is the culprit and I would check it for out of round. If 8-12 ounces of weight brings it to .03 or below thats acceptable. The closer to .00 you get the better. While it is true that the bigger tires don't magnify imbalance as much as the smaller ones, it is also true that any imbalance can sometimes excite the suspension and it can vibrate in harmony with the wheel/tire. I wold take it to a big truck shop that does this on a regular basis. Another critical point is that everything on the suspension must be right and tight;springs,shocks, bushing etc. good luck