Some tires have an inherent pull built into them, not on purpose but they do. The tire companies and automotive manufactures call this tire lead. This will tend to make the vehicle pull to one side and when you are compensating with the steering wheel it makes the steering wheel seem off center. I have seen this for many years at the dealership where I have worked for 34 years. If this is the case you can swap the two front tires side to side and it should pull the other way. The only cure is to keep this bad tire on the rear or replace it.

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Neal

1986 560SL
2004 Chrysler Pacifica
1994 Chrysler New Yorker