It doesnt work on our 19.5 equipped F550s.. didnt work on the GMC 4500s either.Well, I'm sure there's a real cause for the problem. But I've heard good things about the bead balance system that some tire shops uses. Always conforms to the tire and always balances perfect. Gravity and laws of physics are always constant.
I would be curious to know where the defective tires were purchased from...