Back to basics: Tire tread pattern
Sometimes going back-to-basics can make the difference between a quality repair and a failed repair. Let us see how to identify tire tread patterns and their repair considerations.
Where the rubber meets the road, the tire contact patch is the sole part of the tire that comes into direct contact with the road surface.
A tread pattern gives each tire its unique characteristics, which can be symmetrical or asymmetrical and may be directional. Tire damage from a collision is not uncommon. Tread patterns may influence the repair plan when mounting tires or swapping the tire location for drivability diagnostics.
Depending on the tread pattern, tires may require specific orientation and be installed only on one location of the vehicle. Tires have information molded on the sidewall; some is required by law, and standardized.
Most tire manufacturers mold information on the tire sidewall to disclose that the tire has special considerations, including:
- Rotation arrow indicates the direction a tire should roll when mounted on a vehicle
- “Outside” indicates the outward-facing tire sidewall
- “Inside” indicates the inward-facing tire sidewall
Symmetrical tread pattern:
- Symmetrical non-directional tread pattern
- Commonly used for passenger vehicles
- No additional mounting considerations
Directional tread pattern:
- Symmetrical directional tread pattern typically features a V-shaped pattern
- Rotation arrow points forward
- Mounted tires become left or right side specific
Asymmetrical tread pattern:
- Asymmetrical non-directional tread patterns differ between left and right
- Mount with sidewall marked “outside” facing outwards
- Able to swap in all directions if properly mounted
Asymmetrical directional tread pattern:
- Rotation arrow points forward, and the sidewall marked “outside” faces outwards
- Sold as left or right
- Only able to move front to rear, except in cases of staggered tire sizes
To learn more about tire tread pattern, visit the I-CAR Canada course catalogue.