I'm still mystified as to how tires/CV joints/wheels/you-name-it can go in and out of balance as the original post says that this is an intermitant problem, meaning it doesn't happen all the time. I think we need to look beyond items that are either worn out or not (or out of balance or not). Unfortunately I can't think of anything other than what I already posted before.
It's about heat, Karl. Nothing stays consistant when temperature is constantly changing. Things can vibrate if they have slop in them (especially at high speeds). Like my old CV axles, they had slop, and then the axle would settle off to one side, in turn causing an axle-off-center wobble. Then as the joint would heat up hot, the clearance would get sufficiently tight enough to hold the joint pieces and shaft centered and vibration would be gone. Bearings can do similar things too. Tires can flex different with temperature and speed (if there is a belt starting to separate from within or something). Too many factors. But temperature is one BIG factor that is always changing everything.
