Tire Tread Pattern Types
Tread patterns help tune a tire’s traction and handling capabilities to its intended driving conditions. While the most common tread patterns address traction in multiple driving conditions, others are designed further enhance traction to meet specific dry, wet or winter driving challenges. Tread patterns can also influence tire serviceability by either permitting or prohibiting tire rotation and remounting.
Symmetric – When both inboard and outboard portions of the tread pattern share the same design elements. Symmetric tread patterns are the most common design and permit tires to roll in both clockwise and counter-clockwise directions and be fitted to any wheel position. Symmetric tread patterns permit the greatest servicing flexibility by facilitating all of the recommended tire rotation patterns, as well as remounting on the wheel if necessary.
Asymmetric – The outboard portion of the tread pattern is different than the inboard. Vehicles lean when cornering, and in doing so, increase the load/stress on the outboard shoulders of their outboard tires. Featuring larger outboard tread elements, asymmetric tread patterns help stabilize the tread to enhance steering response and cornering stability. By featuring smaller inboard tread elements, asymmetric tread patterns help retain traction in wet and wintry weather. Since the outboard side of the tire is always its outboard side, asymmetric tire patterns allow use of all popular tire rotation patterns.
Directional – The tread pattern features V-shaped grooves aimed towards its shoulders to more effectively evacuate water and slush from between the tread and the road. Tires with directional tread patterns usually feature arrows branded on their sidewalls to identify their intended direction of rotation. Once mounted on a wheel, directional tires are designed roll clockwise on the right (passenger’s) side and counter-clockwise on the left (driver’s) side of the vehicle. While traction and handling wouldn’t be adversely affected in dry conditions, if directional tires were to be accidently installed incorrectly on a vehicle, they would pump water towards the center of the tire, increasing the likelihood of hydroplaning at high speeds when driving through standing water. Directional tires can only be rotated from front-to-rear on one side of the vehicle, prohibiting use of most traditional tire rotation patterns.
Directional and Asymmetric – While the least common, these tires use both directional and asymmetric tread pattern features. Directional and asymmetric tires are typically reserved for use on high performance vehicles or exotic supercars. Tires featuring asymmetric and directional tread patterns must be treated as directional tires for tire rotation. However, if different size tires are specified for the vehicle’s front vs. rear axle, the tires become location-specific and prohibit any tire rotation possibilities.