What Are Directional Tires?by Tim Plaehn
Selecting new or replacement tires can be challenging. Tires should fit your driving style and the typical road conditions you will face. One tire option available is directional tires.
Directional tires have construction and tread designed to rotate in only one direction. They are also called "unidirectional" tires. Directional tires will have an arrow with the word "rotation" on the sidewall showing the proper rotation direction.
Directional tires have lateral grooves in the tread that form a V-shaped tread pattern. The tread design is intended to channel water from the center of the tire outward as the tire rotates.
Directional tires have a higher resistance to hydroplaning. The V-shaped tread pattern will remove water from under the tire faster than regular tread patterns.
Directional tires must be mounted on the car and wheel so that they turn in the correct direction. Directional tires cannot be moved to the other side of a vehicle without being dismounted from the rim, flipped over and remounted.
When buying directional tires, make sure they are mounted to rotate in the correct direction. Directional tires mounted backwards will reduce traction, especially in dry conditions.