Cars driven on recalled tires run the risk of experiencing tread separation, explosion or deflation in the worst cases. The precise hazards vary depending on the nature of the defect responsible for the recall, but it is best to assume that any recalled tire is dangerous to drive on.
Tires are recalled for many reasons, though one of the more common and potentially dangerous issues is tread separation. Tread separation involves the tread of the tire coming loose from the inner tube, potentially leading to a blowout. Such a blowout usually causes the driver to lose control of the vehicle if it is moving at high speed when this occurs, so a serious or fatal accident is possible if a car is driven on tires under recall for tread separation.
Tire recalls are a major reason why it is considered unwise by many experts to purchase used tires. Tire manufacturers are required to register the purchasers of new tires so that they can be contacted in the event of a recall. However, most used tire vendors cannot or do not update these records to reflect the new owner when a tire is resold. This makes it much more difficult for tire manufacturers to inform owners of used tires about recalls effectively.