I recently took one tire back to the dealer because it is cupping and told the guy that it appears to have thrown it's weights. They rebalanced it and called to say it was ready. It the time I dropped it off I did not tell them it was on a trailer. They are LT truck tires. When I picked it up they said the cupping was because of the lack of balance. I mentioned now it was on a trailer. He said"we never balance trailer tires" Asked why "nobody rides in the trailer so any vibration is unnoticed"So I have 3 tires that are wearing well and 1 because lack of balancing is cupped. And around here mounting and balancing is included in the price. So I belive in using that service and extending the life of my tires.