How To Check Tire Tread

Have you ever heard that tires should last for about 50,000 miles or so? You might have, and it’s ok if you don’t know why this is. Thankfully, you don’t need to be an engineer to know when it’s time to replace your tires.

A tire’s lifespan is measured by how long the tread of the tire will last. That’s why you’ll also hear of their lifespan as tread life. Tires are known as wear items as the tread gradually wears down, and when it’s worn to a certain point, it’s time to replace your tires.

So, let us ask you this: do you know how much tread is left on your tires? Don’t worry if you don’t. That’s exactly why we’re here. We’re going to tell you everything you need to know about tread life and even give you a guide on how to measure your tire’s tread.

What is a good tire tread depth?

As long as the tires aren’t bald, they’re good. Right? Not exactly. A tire’s tread pattern consists of more than just tread blocks. The sipes and grooves throughout the surface of the tread are in place to enhance the tire’s safety and provide the tire with enhanced performance characteristics. So, even if some tread blocks are still left, that doesn’t mean the tire is still safe to drive on.

Most tires start with a tread that measures roughly 11/32-inch deep and are considered bald when they are worn down to a 2/32-inch tread depth. At that point, all of the sipes and grooves have worn away, and the tire can no longer function properly. Therefore, you want to use either a tire tread-depth gauge or a penny to routinely inspect your tire tread.

Is the penny test for tires accurate?

That’s right. We said penny. It just so happens that Lincoln’s head is just 2/32 of an inch from the edge of the penny. That means you can use a penny as a tool to measure your tire’s tread depth. Mind you, a dedicated measuring instrument is far more accurate. Still, the penny method is accurate enough to anyone who’s more concerned with their own safety than running tires for as long as possible.

How can you tell if a tire has bad tread?

Before concerning yourself solely with regular tread wear, you should know that irregular tread wear is just as bad. In fact, it can be even more pressing to replace a tire with cupping, flat spots, and other tread irregularities than you might think.

Furthermore, the tread isn’t the only part of the tire to keep an eye on. Issues throughout the tire can be just as pressing. Therefore, you’ll want to understand and keep an eye out for the following conditions:

Dry rot

• Many people may not be aware of it, but a tire’s life expectancy is based on more than just tread life. Exposure to the sun’s UV rays and to the elements can cause dry rot, where the tire’s rubber starts to break down and slowly disintegrate. Dry rot is easy to spot as it creates cracks throughout the tire’s surface. Also, if you touch the tire it’ll feel stiff, dry, and brittle. If you see it, you should replace the tire immediately as a blowout can occur without warning.

Foreign objects

• Keep an eye out for nails, staples, broken glass, and other junk embedded in a tire’s tread. They may seem harmless enough but can create a slow leak issue which may lead to several additional issues. Not only that, but the hole can increase in size, damaging the tire beyond repair.

Bubbles

• If the tire’s integrity is compromised, you will notice a bulge on the surface. This bulge represents a weak point that can blow out at any minute. Of course, this means you should replace the tire immediately.

5-step guide to checking tread depth

With the knowledge of issues outside of tread depth to keep an eye out for, we can talk about how you measure your tread. So, break out your lucky penny, a wheel chock, and some jack stands.

1. Park the vehicle

It goes without saying that you should never work on a vehicle without it in park and the parking brake engaged. Otherwise, the vehicle is liable to roll and severely injure you.

2. Turn your front wheels to one side or another

Space can be limited around the front tires. However, by turning the wheel to one side or another, you’ll expose a considerable portion of the tread, giving you enough room to work. The good news is that there should be more than enough room around the rear tires as well.

3. Check tread depth

With Lincoln’s head facing the tire, place the edge of the penny between tread blocks. As long as Lincoln’s head is covered, you have at least 2/32-inches of tread. Repeat this at multiple locations of the tread from front to back.

4. Continue to check

Make sure to check tire tread in multiple places, the more the better. This is the only way to ensure the tire is wearing evenly.

5. Repeat on all four tires

One tire’s condition isn’t representative of the other’s. Take the time and repeat the process on all tires to be sure your vehicle is safe to drive.

Understanding uneven tire wear

What if the tread isn’t wearing evenly across the surface of the tire? Should you base your decision to continue to use the tire on the highest or lowest point? Neither.

Uneven tread wear is a sign the tires aren’t being cared for correctly or there’s a mechanical issue with the vehicle. Either way, you’ll need to familiarize yourself with the tread pattern to determine if the issue is able to be corrected or if you need a new set of tires and mechanical repairs. Below are some example of irregular wear patterns to look for:

Excessive wear at center of tread

Tires that are worn more at the center than the edges might be overinflated. This is because overinflation reduces the contact patch, forcing the center-most portion of the tire into the road more than the outside edges.

Wear at the front tire’s outside edge

Wear to the outer edges of the tires is typically linked to an alignment issue. Because the tire isn’t aligned correctly, it is dragging instead of rolling. The excess friction is going to create excessive wear on the edge of the tire.

"Cupped" wear

Cupped wear looks like a series of flat spots throughout the tread. This issue is typically linked to ball joints, shocks, tie rod ends, or other front-end parts that are too worn to keep the tire in good contact with the road, causing the tire to bounce and create an uneven wear pattern.

"Feathered" wear

If tread ribs are higher and sharper at one edge than the other, this can be a sign of improper toe or caster/camber. Unfortunately, that may be due to poor wheel alignment or faulty mechanical components.

Getting the most miles out of your tires

You’re bound to wonder how you can get the most out of your tire tread. After all, tires aren’t cheap, and it’s not always easy to get an appointment with a good tire shop—unless you pre-book an appointment at our nearest tire service center.

The good news is you’re not powerless in the face of a tire’s march through time. In fact, some basic maintenance is all it takes to ensure your tires will last the full potential of the tread life – or possibly more.

Stay within the tire’s limits

Tires are designed with specific conditions in mind, and it’s best to limit their use to those conditions. This means avoiding terrain they aren’t intended for, staying below the speed rating, and switching the tires seasonally unless you’re running all-season tires.

Rotate your tires often

Tires should be rotated every 5,000 miles or so. If your engine’s oil should be changed in similar intervals, it can be easy to remember to do both at the same time. Otherwise, you should keep track of your mileage and make sure that you rotate the tires accordingly.

Keep up with tire pressure

Tire pressure will fluctuate, even if the tire is in perfect condition. As a rule of thumb, you should check and adjust your tire pressure once a month to promote optimal performance and tread life.

Balance the tires regularly

As tires wear down, their mass will change, and that means they will fall out of balance they will fall out of balance. You should have your tires rebalanced every 12,000 miles to prevent wear issues.

Perform necessary mechanical repairs

Don’t just keep up with the tires. It’s important that you keep up with the routine maintenance schedules in your owner's manual for the mechanical components, or have a professional inspect them for you. Again, their condition can lead to excessive and irregular patterns that will destroy your tires.

You may feel overwhelmed with all this new information. Don’t be. It sounds like there’s a lot more to it than there actually is. IIf you prefer to have a professional maintain your tires or simply have questions on the condition of your tires, we encourage you to call our customer service line for advice so you can drive confidently on any terrain.