If it's a bad tire (usually just one), the tread wear tells the story.

The bad one has premature wear, and if it's tread separation, its wear pattern is in even patches (called scalloping in the tire world).

Moving the offending tire if on the front to the rear reduces the vibration somewhat, but its far worse if moving the bad tire from the rear to the front.

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car