For the inside of your tires to be worn by a bent axle, it would have to have been bent downwards & a cause toe out or / - \ kind of thing. To wear your tires that quickly, the bend should be quite visible. If they jacked from the center of an axle, it would cause toe in or \ - /. Something else has probably caused this over more than one season of wear (unless you've been traveling an awful lot).
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