Road Crown and Camber
A crowned road means that the outside/right hand side of the lane is lower than the left side of the lane. This improves the drainage of the road but adversely affects vehicle handling. Road crown must be compensated for in alignment settings because a vehicle driving on a crowned road leans to the right, causing some weight transfer to the right, and the camber changes slightly more positive. This combination creates a pull or drift to the right. Most alignment technicians adjust the vehicle with a slightly more positive camber, usually 1/4°, on the left to compensate for the road crown. This slightly more positive camber will not cause a noticeable pull when driving on a flat road. However, if camber is unequal from side to side with a difference greater than 1/2°, the vehicle will pull to the side with the most positive camber. If the specifications allow, 0° to ±.5° is usually best for tire life and vehicle handling.
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