Tire wear 101

Uneven tire wear is usually caused by improper wheel alignment, overinflation, underinflation or a worn-out suspension. It can be helpful to know the different uneven tire wear patterns below and what they may suggest about your car.

By closely examining the tires, you may be able to determine if the tire is wearing properly or if replacement should be considered.

Excessive wear on the inner or outer edge of the tire, known as "toe wear" or, in more extreme cases, as "camber wear," suggests something may be wrong with the wheel alignment, according to Bridgestone. To help fix the problem, you'll likely need to make an appointment with a mechanic.

If the center of the tire is quicker to wear than the edges, then the tire is likely overinflated. Find the proper tire pressure for your vehicle by looking at the sticker typically found in the doorjamb on the driver side or in the owner's manual, according to Edmunds. Adjust the tire pressure accordingly for a smooth, safe ride.

If the outer edges of the tire wears faster than the center, the tire is likely underinflated, says Popular Mechanics. Follow the tire pressure recommendation on the side of the tire and add air to the tire as needed.

A diagonal scalloping on the tire, known as "cupping wear," suggests the suspension may be worn, bent or somehow compromised, says Pep Boys. This is a serious concern, and you'll probably need to make an appointment with a mechanic immediately.

Patchy wear implies the tire is out of balance. Have a mechanic spin and rotate your tires, as this can help equalize the wear. The National Highway Traffic Safety Administration (NHTSA) suggests having tires spun and rotated every 5,000 miles, but it's a good idea to consult your owner's manual first.

Tire feathering, where tread feels smooth on one side and jagged on the other, is typically caused by wheel misalignment. When tires tilt inward or outward, they unevenly scuff the road at an angle causing the feathered wear pattern, according to Goodyear Auto Service.

When measuring wear, first check your tire’s built-in tread wear bars, and look for uneven wear, cracks, bulges, discoloration or dry rot. Then measure the tread depth with a gauge or scanner. For a quick estimate, insert a penny head-down into the tread. If you see the top of Lincoln’s head, replace the tire, explains Auto Zone.

Tire wear can negatively impact your vehicle’s safety, fuel efficiency, and overall performance. When tire tread gets too low, you can lose traction, turns become less stable and stopping requires more distance, especially on wet or uneven roads, explains Consumer Reports. Worn tires increase your blowout risk and make your engine work harder, burning more fuel. Over time, excessive wear can strain the suspension and create noise and vibration.

How can I extend the life of my tires?

With proper care, you can make your tire’s last longer with these tips from Forbes.

• Maintain the manufacturer's recommended tire pressure
• Rotate tires every 5,000 miles for even wear
• Check your alignment annually or if there’s pulling, vibration, or uneven tread wear
• Regularly inspect tires for damage
• Avoid road hazards that may damage your tires
• Choose all-season, performance, or winter tires for your conditions
• Reduce stress on your tires by not driving aggressively

How often should I check my tires for wear and tear?

A monthly inspection of all tires, including your spare, is the frequency recommended by the National Highway Safety Administration (NHTSA). Also, inspect your tires before long trips and after driving on rough terrain. For best results, check your tire pressure when tires are cool. Look for:

• Uneven tread wear patterns
• Tire caps on your tire valves
• Overloaded vehicles
• Cracks or bulges in the sidewall
• Embedded objects like nails or glass
• Low tire tread depth

When repair is no longer an option, here’s when tire replacement is necessary.

• Low tread depth: Tread below 2/32- 4/32 of an inch means it’s time to replace, says Tire Track.
• Visible damage: Cracks, bulges, or deep cuts in the sidewall aren’t repairable and require replacement.
• Irregular wear patterns: When there is cupping, feathering, or excessive wear, replacement is safer than repair.
• Old tires: Tires should be replaced after five to six years, regardless of wear, according to Edmunds.com. Check the four-digit manufacturer’s date molded into the sidewall. The first two digits indicate the week, the last two the year.
• Decline in performance: If you notice reduced traction, longer stopping distances, or increased road noise, your tires may be past their prime.