Your tires are the only point of contact between your vehicle and the road. When they wear down unevenly, traction, control, and handling can suffer. Luckily, your tire wear patterns can tell a story if you know how to read them. This guide will help you recognize the signs that can help you stay ahead of potential problems in not just your tires, but your entire vehicle.

Understanding tire wear

Ideally, tires should wear evenly under normal drive conditions. Uneven wear is often a sign of mechanical issues or improper maintenance and can lead to reduced traction, decreased fuel efficiency, and compromised handling.

Different tire wear patterns can help you stay ahead of potential problems and extend the life of your tires. Learning to recognize the signs and read your tire wear can give you clues about your vehicle’s health.

The role of rubber in tires

Tires comprise rubber and a host of other additions. Pure rubber (natural or synthetic) becomes brittle as it cools and gooey as it warms up. This characteristic gives tires their seasonal differences:

• Summer tire treads are shallow and quite stiff to help move water through. The stiffness also stands up well to heat created by the sun shining on asphalt.
• Winter tire treads are deeper and slightly wider, and they also give a little more. This helps them grip a wintery road and push slush and snow through.

How to check your car’s tire tread

The surface of your tires has plenty of clues on your vehicle’s health and maintenance.

Centre wear

• Diagnosis: Overinflation.
• Appearance: The tread in the middle of the tire may appear worn or bald while edges remain intact.
• Cause: Over-inflated tires bulge in the centre, inevitably causing wear to the centre of the tread.
• Solution: Examine and adjust tire pressure to the manufacturers’ recommended PSI. You’ll find this number on the driver’s side door sticker and in your owner’s manual.

Edge wear

• Diagnosis: Underinflation.
• Appearance: The tread in the middle will curve deeper compared to the sides or shoulders of the tire.
• Cause: Without maintaining proper shape, under-inflated tires will force the weight of the vehicle to rest on the outer edges of the tire.
• Solution: Check and maintain tire pressure at recommended levels to ensure an even distribution of weight along the tire.

Cupping wear

• Diagnosis: Suspension issues.
• Appearance: The tread appears to have a wave pattern with alternating high and low arcs along the tread. At certain speeds, the vehicle may vibrate or produce rumbling noises.
• Cause: Worn out or faulty suspension components can cause the tires to bounce excessively. Most commonly shocks or struts that are worn out or require inspection will cause excessive bouncing and waved treads on your tires.
• Solution: Inspect and address issues with the suspension system.

Patchy or spot wear

• Diagnosis: Unbalanced tires.
• Appearance: Irregular wear appears in certain patches surrounding the tire. This may cause the vehicle to shake at higher speeds.
• Cause: Unbalanced tires can cause an uneven distribution of pressure and lead to erratic wear.
• Solution: Have your tires professionally balanced.

Shoulder or one-sided wear

• Diagnosis: Alignment issues.
• Appearance: One side of the tire will appear significantly more worn than the other. You’ll also notice shoulder wear if your vehicle pulls to one side frequently.
• Cause: Misaligned wheels can cause tries to tilt either inward or outward, which leads to uneven contact with the road surface.
• Solution: Professional wheel alignment will correct any misalignment issues.

If you notice any of these symptoms, have your tires rotated and the underlying cause repaired. In some cases, you may need to replace all four tires. (Never replace just the damaged tire, because your drive will become uneven and irregular.)

Preventing uneven tire wear

Regular maintenance can help extend the life of your tires. Here are some tips on regular tire care:

• Check tire pressure regularly: Use a quality tire pressure gauge and ensure they’re inflated to the manufacturer’s recommended PSI. Check your tire pressure at least once a month and before longer trips on the road.
• Rotate your tires: Rotate your tires every 8,000 to 10,000 km, or at every oil change. Ensure your tires are balanced at every rotation or at tire installation.
• Get regular alignments: Schedule a wheel alignment at least once a year or if you notice uneven wear.
• Inspect suspension and steering components. Have your suspension system checked, especially if you’re experiencing excessive bouncing or vibrations along with uneven tire wear.

For support in reading your tire patterns, visit a NAPA AUTOPRO service centre. Our experts will answer questions about tire wear and tire inspection. You might just be able to uncover minor issues by reading your tire wear patterns before they turn into major repairs.