Tire Wear Bar Indicators: What Tread Markers on Tires Mean

Most tires have a built-in feature that tells you when it's time for new ones — no guesswork required. They're called tire wear bars (also known as wear indicators), and they're molded directly into the tire's tread.

As your tires wear down, the wear bars become more visible. When the tread is level with the wear bar, your tires are at 2/32," which is the minimum safe tread depth according to the U.S. Department of Transportation. It's time to replace them.

What Are Tire Wear Indicators?

A tire wear indicator is a built-in feature that is molded into a tire to help drivers measure treadwear so they know when it is time to get new tires. Treadwear indicators are also sometimes referred to as tire change bars, tire bars, or tire wear marks, markers or markings. They are located on the tire read, which is the part of the tire that touches the road.

There is no industry-wide standard for how treadwear indicators look or where they are placed. Manufacturers are required to include them, but how they do it is up to them. Here are the most common types:

• Wear bars: Wear bars are small, raised rubber bars molded directly into the grooves of the tire tread, set at 2/32" high. As the tire wears down, the bars become more visible. When the tread is level with the bar, it's time to replace the tire. Bridgestone, Goodyear, Pirelli and most other major brands use wear bars as their primary indicator. These are the most common type of tire wear indicator.

• Tread stamps: Some manufacturers use letters or logos stamped into the tread itself. Continental uses DWS on select all-season tires, which stands for dry, wet, and snow. As the tire wears, the letters disappear in reverse order — first the S (no longer safe for snow), then the W (wet conditions), then the D (replace the tire). Michelin etches a tiny Michelin Man logo into the shoulder of the tire near the wear bar, making it easier to locate.

No matter which type your tires use, the rule is the same: If any part of the tire reaches 2/32", it's time to replace it, even if other areas still have tread.

If cost prohibits you from replacing your tires, Tire Agent offers numerous payment plans.

Answers to FAQs About Tire Wear Bars & Indicators

Where can I find tire wear bars?

The location of tire wear bars depends on the manufacturer, but wear indicators are generally spaced evenly around the circumference of the tire, sitting in the grooves. When you inspect your tires, check the entire surface of each one, as tires can and do wear unevenly. If any part of a tire is at 2/32" or lower, it's time to replace it, even if other areas still have tread. In a separate post, we explain how to use a coin to check tread depth.

Can I drive on tire tread bars?

Technically yes, but it's not safe. When the wear bars are flush with the tread, your tires are at the legal minimum (2/32") and their ability to grip the road, especially in wet or slippery conditions, is seriously reduced. If your wear bars are becoming visible, start shopping for new tires now.

Should tires be replaced before or after tire tread bars show?

Before. When tread reaches 2/32", a tire is considered bald and should be replaced. But you don't need to wait that long. We recommend starting your search when tread hits 4/32". That gives you time to shop without pressure.

What distance are wear indicator bars set?

Wear bars aren't set for distance; they're set for tread depth. How quickly you reach them depends on how much you drive and the tire's expected mileage. On a 60,000-mile tire, with average annual driving of 10,000 to 15,000 miles, the wear bars will typically start showing around year four.

What does it mean when wires are showing on tires?

If you see a white thread or wires showing in your tire tread, stop driving immediately. Those visible threads or fibers are the internal cords used to give the tire its structure. When they're exposed, the tire is well past its safe limits and could blow out without warning. Do not drive on a tire with visible wires or cords.

How long will a tire last with threads showing?

It won't, and you shouldn't try to find out. A tire with visible threads or cords can fail at any time, without warning. There is no safe mileage left on that tire. Replace it before you drive the car again.

Does a TPMS warn you when tires need to be replaced?

No. A TPMS (tire pressure monitoring system) only monitors air pressure. It has no way to measure tread depth or wear. A tire can be perfectly inflated and completely bald without ever triggering a TPMS alert. For more on how TPMS works, see our related article.

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