thrust angle causes the rear tires to track improperly to the left or right of the front tires (dog tracking).
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Negative thrust angle means the rear tires are tracking to the left of the front tires.
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Positive thrust angle means the rear tires are tracking to the right of the front tires.
Improper tracking can cause undue tire wear, a lead or pull and a crooked steering wheel. Excessive thrust angle can usually be corrected by adjusting
the rear wheel toe so that each wheel has one-half of the total toe measurement.