That flat spot is usually the result of the hardening tire material. The tire just keeps the shape it had during storage. For some time the effect can be reversed. The tire makes a slight thumping sound that goes away after some driving. If it sits too long the shape stays and the tire must be replaced.
Iīve seen the flat spot once. The vehicle stood for about a year and the tires were not properly inflated. The flat spot was about 3" long and the tires kept it while we pushed the car around. I didnīt really believe it before.
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If it isnīt broken, it doesnīt have enough features yet.