FOUR TIRE TREAD TYPES
Tires are designed with different types of tread, and each one is meant for different road conditions and driving styles. The four types of tire tread are directional, symmetrical, asymmetrical, and directional/asymmetrical.
Directional tread is meant to roll in one direction and typically features arrows which display that direction. This tread type allows for water to be displaced from the tire to avoid hydroplaning. Directional tires should be rotated front to back from the side that they are in since each tire is designed and angled to perform best on their specific side.
Symmetrical tire tread has the same pattern – continuous grooves and/or independent lugs – across the whole tire. This type of tire is the most common and found on most non-high-performance passenger cars because it is typically quiet and long-lasting. Symmetrical tires can be rotated in many different ways, which helps to prolong the life of the tires and makes them more versatile.
Asymmetrical tire tread, most commonly found on sports cars, is a bit of hybrid in that it combines a variety of tread patterns for maximum grip on both wet and dry roads. Usually, the inside and middle parts of the tire will be designed for wet and/or winter traction while the outside of the tire will have large tread blocks for maximum cornering capability on dry surfaces. To ensure that the tires are positioned correctly on the car (to maximize handling capabilities), the sidewalls are marked "outside only" and "inside only." Many different rotation patterns can be used for tires with asymmetrical tread patterns.
Directional/asymmetrical tire tread is the best of both worlds – it features the V-shaped pattern of the directional tread for discharging water away from the tire and the dry weather traction of the asymmetrical tread. You should follow the same rules as directional tires when it comes to rotation patterns. Vehicles equipped with different size tires on the front and rear (staggered), prohibit the ability to rotate directional/asymmetrical tires unless they are remounted.