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Tire Lead Diagnosis

Lead is the deviation of the vehicle from a straight path on a level road with no pressure on the steering wheel. Lead can be caused by:
- incorrect wheel alignment
- dragging brakes
- incorrect/uneven tire pressure
- defective tires

If defective tires are suspected in a lead condition, use the following steps to determine the defective tire:
1. Rotate the two front tires.
2. Road test the vehicle. If the vehicle leads to the opposite direction, one of the front tires is at fault.
3. Rotate the two front tires back to their original position.
4. Rotate one of the front tires with its corresponding rear tire on the same side of the vehicle.
5. Road test the vehicle. If the lead is corrected, install a new rear tire. If the lead remains, install a new front tire on the opposite side of the vehicle.