Radial Tire Lead

"Lead" is the deviation of the vehicle from a straight path on a level road, with no pressure on the steering wheel.

Lead is usually caused by:
^ Improper wheel alignment.
^ Uneven brake drag.
^ Lateral tire forces due to tire construction.

The way in which a tire is built can produce lead in a vehicle. An example of this is placement of the belt. Off-center belts on radial tires can cause the tire to develop a side force while rolling straight down the road. If one side of the tire has a slightly larger diameter than the other, the tire will tend to roll to the side with the smaller diameter. This will develop a side force which can produce lead.

Part of the lead diagnosis procedure is different from the proper tire rotation pattern shown in the owner's and service manuals. If a medium-to-high mileage tire is moved to the other side of the vehicle, a temporary increase in tire noise or tire roughness may occur. Tire noise and/or roughness should diminish within a short time as the tire wears. REAR TIRES WILL NOT CAUSE LEAD.