Tread Confidently: Know When To Replace Your Tires

Article overview

• Don’t judge a tire by its tread alone: Hidden damage like sidewall cracks or bulges can turn your road trip into a roadside emergency.
• Tire quality affects more than just comfort: Worn or underinflated tires can reduce fuel efficiency, handling and safety, especially in wet conditions.
• Know the warning signs: Shallow tread depth and uneven wear to unusual vibrations and visible bubbles, your tires might be telling you it’s time for replacement.
• Stay safe with proactive care: Routine tire checks, rotations and prompt replacement of damaged tires can help you avoid costly repairs and potential accidents.

Your tires may look fine, but worn tread, tiny cracks or expanding bubbles can turn a road trip into a roadside emergency. If you’re unsure when to replace your tires, we’re here to help! 

Find out why tire quality matters and get familiar with the signs of damaged or dangerous tires. With the right tire knowledge in hand, you can save time and money, but most importantly, you can better ensure your safety behind the wheel. 

Why tire quality matters

Worn-out tires aren’t just risky—they’re expensive in the long run. Expect decreased fuel economy, a decline in handling, reduced traction and generally bumpy or uncomfortable driving. Consider the following:

• Research from AAA reveals that driving on relatively worn tires at highway speeds in wet conditions can increase average stopping distances by a staggering 43%, or an additional 87 feet—more than the length of a semitrailer—when compared with new tires.
• Poor alignment can reduce tire life by up to 30%. That’s because when wheels are misaligned, tires don’t make proper contact with the road, leading to certain areas of the tire wearing out faster than others. 
• Underinflated tires can reduce gas mileage by 3% or more due to rolling resistance. The engine must work harder to force an underinflated tire to roll, thereby consuming more fuel. 
• Blowouts from bad sidewalls can cost you hundreds in repairs or towing, and in many scenarios, can even result in accidents. About 33,000 tire-related crashes happen annually, according to the National Transportation Safety Board. At least 2,000 of those are blowout related. 

Should you replace your tires? Look for these signs

Shallow tread depth

Tires should be replaced once the tread depth reaches 4/32nds of an inch, which is when stopping distances have already begun to deteriorate significantly. To gauge tread depth, use the simple quarter test.

Insert a quarter upside down into your tire tread. If you can see the top of Washington’s head, it’s time for new tires. If the top of Washington’s head disappears into the tread, you have more life left on your tires. 

Uneven wear

When was the last time your tires were rotated? It’s an important question because tires that aren’t regularly rotated and balanced will wear unevenly. Rotating your tires prolongs their life and provides better overall performance; expect to do this every 5,000 to 8,000 miles. For your car’s specific rotation frequency and pattern (some are front-to-rear, others side-to-side), check your owner’s manual.

Bad vibrations

Rumbles from underneath the seat might mean your rear tires are out of balance, whereas a bumpy feeling from the steering wheel could indicate something even more serious, such as a suspension issue or the wheels being out of alignment. 

Sometimes, hitting a curb or a pothole can cause tire damage that creates this sort of rumble or unusual vibration. In severe impacts with a pothole, your tire’s rim can get bent or cracked, leading to air loss and sometimes even a hazardous tire blowout. Anything other than a smooth ride should be inspected by a qualified automotive technician. 

Sidewall cracks

Do you drive in extreme heat or snow? Harsh elements, as well as UV exposure, can cause tire rubber to break down and lead to cracks on the sides of your tires or separation of the tread—even if they’re not worn down in the center.

Sidewall cracks can also be the result of hard impact with an object, potentially leading to leaks, deeper fissures or even separation. To prevent tire blowout, replacement is generally advised.

Tire bubble or bulge

A bubble or bulge on the sidewall of your tire indicates a problem that’s rarely fixable. In almost all scenarios, tire replacement is necessary. That’s because most tire bubbles or bulges are the result of high-impact damage, and when not addressed promptly, the tire is at risk of blowout. 

Quick repairs for common tire issues

Many tire issues are the result of small punctures or slow leaks that do not require replacement. Once identified, these issues can be repaired quickly and easily in a few simple steps. For example, learning how to patch and plug a tire is a worthwhile skill for all drivers to have. It’s also crucial to know how to properly inflate your tires to ensure your safety and your vehicle’s performance and efficiency on the road. 

Vehicle inspection benefits for members

Whether you’ve determined it’s time for new tires or you’re still seeking the opinion of a qualified technician, it’s worth noting that AAA Members receive a FREE multi-point vehicle maintenance inspection (upon request with any paid service) and 10% off labor (up to $75) at AAA-owned Car Care Centers and AAA Approved Auto Repair facilities.

FAQs: Tire Safety & Replacement

Q1: How do I know if my tires need replacing?

Use the quarter test: Insert a quarter upside down into the tread. If you can see the top of Washington’s head, your tread is too shallow and it’s time for new tires. Also watch for bulges, sidewall cracks and uneven wear.

Q2: What causes tire blowouts?

Blowouts are often caused by underinflation, sidewall damage or tire bubbles resulting from impact with potholes or curbs. These issues weaken tire structure and can lead to sudden failure.

Q3: How often should I rotate my tires?

Tires should typically be rotated every 5,000 to 8,000 miles. Regular rotation helps extend tire life and improves vehicle handling and performance.

Q4: Can I repair my tire instead of replacing it?

Small punctures and slow leaks can often be patched or plugged. However, sidewall damage, bulges or cracks generally require full replacement for your safety.