Holy Cow, 100,000 miles out of a set of radial tires???
The quality of rubber is not the greatest, and most modern drivers in Model-As "over-drive" the tire in corners anyway. If someone gets 12k-15k miles, to maybe 20k out of a set of tires, (even back in the day) that was considered a lot of driving. Times have changed with advances in automobiles. Be content with 12k-15k miles of service life.
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