It can be both disheartening and dangerous when your new tires start developing uneven wear patterns. These tread formations both shorten the tire's service life and ruin its performing capabilities.
But, what causes them and why do they appear on the tire tread?
Well, the short answer is that there are multiple reasons. Unfortunately, tires can develop irregular or uneven wear patterns easily due to various problems from tire pressure, improper alignment, and reckless driving.
What Different Tire Wear Patterns Mean?
Different tire wear patterns can develop on the tread area throughout the tire's lifespan. If the wear is even, everything is in order. However, if the wear is uneven it can be caused by versatile problems from the wheel alignment of the car to your driving habits.
It is important to recognize uneven tire wear on time. In such cases, remedies are still available for the problems. Both tires and vehicles need to be checked regularly to ensure their driving and performing safety.
Which Tire Wear Patterns are Irregular?
There are various uneven tire wear patterns that you need to look out for. As their causes are versatile, the wear on the tire will actually tell you, or your tire expert, what the leading cause may be.
While we do not have a tire damage chart, we still took the extra step to show tread wear issues and provide explanation for each one. Therefore, take a look at the list below to see the categories of unusual wear patterns.
Patchy Tire Wear
Patchy wear means that the tread is developing little dips across the footprint. In other words, the tread is wearing away in patches - where the tread wear manner got its name from. This causes the tires to bounce during the drive, while also ruining the traction and handling. So, if you notice anything like this, contact your tire mechanic as soon as you can.
What causes wavy tire wear patterns?
Patchy or wavy tire wear is mainly caused by the tires being out of balance. Rotating the tires - changing their position on the vehicle - will help prevent the wear from becoming unmanageable. Tire rotation every 5,000 to 7,000 miles will help even out the tire tread wear.
One-side Tire Wear
This type of treadwear is also called camber or toe wear. It happens with the tires wearing on outside or inside of the footprint. When the inner or outer side of the tire is wearing excessively, do an alignment check as soon as possible.
Disproportionate outer wear or inner edge wear happens due to poor alignment, which causes the vehicle to pull to one side. It places more pressure on the contact patch of the tire, advancing the wear on that tread side. Usually, when this happens, the same side of both front tires will have irregular treadwear.
If you look at your left or right front tire and see a slight tilt to them, there is a definite problem. Therefore, when you notice the vehicle is pulling to the side, have the car checked. As long as the wear is not too far along, the proper alignment of the wheels should combat the uneven formations.
What are Toe Angles?
So, why are these common tire wear patterns called toe or camber wear?
When the tires are actually parallel to the center thrust line, it is called the zero toe angle. Anything varying from this is a positive or negative toe, which results in the tire's toe wear. When the toe angle is incorrect - due to problems with the vehicle usually - the tires will develop irregular toe wear on the inner or outer edge.
The excessive positive or negative toe will significantly shorten the tires' service life. An example of this is both front tires wearing on inside of the tread area.
What are Camber Angles?
When the tire and wheel assembly have a tilt (inward or outward) viewed from the car's front, it is a camber. It should go without saying that if the tires are not correctly centered, their contact patch will not be even - causing uneven tire wear patterns.
The tire's camber can be positive or negative, depending on which way the tire is leaning. A negative camber appears when the tire's top is tilting inward (towards the vehicle). A positive camber happens when the top of the tire is leaning outward (away from the car).
No matter which way the tire is tilting, it will cause camber wear to appear on the tire's inner or outer edge. For this reason, tire wear on inside edge or the outside one is dangerous. Therefore, when you notice it, check and fix the vehicle.
Tire cupping is a whole different issue. Cupping tire wear patterns are recognizable from their diagonal and scalloped wear. Scalloped tires are bouncy, as their footprint does not contact the road evenly. This type of treadwear (tire spots) is usually caused by a faulty suspension system.
Have the vehicle's suspension checked when you feel vibrations during the drive! Suspension parts, like most vehicle parts, can bend or wear out, which will cause these issues to appear. Apart from remedying the issue when it arises, it is also a good idea to change the suspension system or have someone take a look at it during your regular vehicle maintenance.
This type of wear is also called bad shock tire wear. When tires are experiencing shocks during their performance, the footprint does not contact the road surface fully. Therefore, tire wear from bad shocks results in a bumpy tread area.
Improper tire pressure levels cause center wear, which creates a dent in middle of tire tread. All tires, no matter their type, have a recommended pressure level that they should be running at. Look for these pressure levels in the owner's manual of the vehicle.
However, the overinflated tires have their center tread area slightly bulged out due to the excessive air present in the tire. This makes the tire run only on the tread's center, causing its accelerated wear. As a result, these tires wearing on the inside quicker compared to the two shoulders.
To remedy this wear pattern, while the treadwear difference is still not too enormous, bring down the tires to their proper inflation pressures.
If you have excessive wear on the outside of your tires, the tires are probably experiencing edge or feather edge wear, which is the opposite of center wear. It happens when the tire pressure in the tires is too low when the tires are under-inflated, therefore it is also called underinflated tire wear. If the tires are not running on the recommended air pressure, only the shoulder area will be in contact with the road surface.
This causes feathering or accelerated shoulder wear, in other words uneven tire tread wear. Check the tire pressure regularly to make sure the tires are always running with the correct air pressure levels. As long as the tire is able to maintain its good shape, the tread wear will be even.
Tire pressure is one of the most important aspects we need to consider when thinking about the safety of the tires and wheels.
What Is a Heat Ring on a Tire?
A heat ring on the tire sidewall appears when a tire is driven while it is severely underinflated. A tire heat ring around the tire sidewall is dangerous. This happens when all pressure accumulates on the tire's sidewall, which significantly damages the tire's sidewall. The result of a heat ring tire is irregular wear, and it can lead to sidewall separation.
What are the Early Signs of Uneven Tire Wear?
Of course, tires do not wear out from one day to the other. The tire wear, even when it is irregular, is gradual and there are multiple signs that let you know that something is amiss.
So, what do you need to keep an eye out for to protect your tires?
Visible Tread Wear
Some uneven tire wear patterns are visible even when the tires are mounted on the vehicle. If you notice any possible issues with your tires, it is best to contact your tire expert. Taking your car to the mechanic for regular check-ups will also not hurt.
Vibrations and Noise
Disturbance in your driving comfort might be due to tire wear issues. Irregular tire wear patterns can create excessive road noise and vibrations during their performance. This is not just annoying, but it might be a sign that the tire tread is wearing unevenly.
Visible Tire Damage
Tire damage can be visible as well. Bulges or cracking on the tires can be the result of them being used at incorrect tire pressures. Unfortunately, most types of tire damage are not correctable. Yet, they will still let you know of issues and that the worn and damaged tire set needs to be changed for new tires.
Why Does the Tire Tread Wear Unevenly?
As we have mentioned before, uneven tire wear patterns develop due to various issues. While preventing some problems is impossible, often the issue is due to negligence.
Center and shoulder wear are the result of incorrect tire pressure levels. Be sure to check the tire pressure regularly, especially when significant temperature changes occur in your area.
The owner's manual of your car should let you know of the proper air pressure to use with your tires. This will ensure consistent road contact of the footprint, which allows the tire to evenly circulate the driving pressure. In other words, the tread will ensure even wear from the edges to the center.
Rotating the tires mounted on the vehicle regularly will ensure their even wear. This preserves the tread life of the tires, allowing their longer usability.
Rotating tires means moving them from one axle position to another. There are different rotational patterns that can be used with versatile cars. Yes, tire set rotation is even possible for staggered vehicles.
For most tire-related issues improper alignment is the culprit. When the wheels are not properly balanced, the tires are unable to perform in their intended manner.
Therefore, the wheel alignment plays a big role in the tread wear as well. It can cause irregular, excessive wear on both the edges and the center tread, significantly shortening the usability of the tire. Having the alignment checked often will allow you to combat any such issues before they arise.
Problems with the Suspension System
Uneven tire wear may indicate problems with the suspension system, which can also create issues. Not only does it result in cupped tires, but it will ruin the driving comfort of the vehicle during its performance.
Having the suspension of the car checked (by a professional) every 50,000 miles will guarantee a smoother ride and even tire wear. This will help identify bent or worn parts, to ensure the car's safer performance.
We know, we know...
We also love to step on the gas and let loose at times. However, neither your car nor your tires will thank you for it.
Adding more power into the equation of tire wear will not only accelerate the tread wear, but it can also cause uneven formations. This is more prevalent on the tire's shoulders than anywhere else.
Accelerated tire wear appears where more pressure is placed on the footprint. Therefore, faster and/or reckless cornering will place needless pressure on the outer shoulder, causing uneven tire wear to appear.
So, slowing down a bit will help you lengthen the lifespan of your tires.
What are the Remedies to Uneven Tire Wear?
As long as the tires are not too worn out, the tread can still be saved. Each tire problem has a unique solution.
Depending on the treadwear manner, correcting irregular formations requires different remedies. These are:
- Patchy wear = Tire rotation
- One-sided wear = Alignment correction
- Cupped tires - Check suspension parts
- Center wear = Deflate the tires a bit
- Edges wear = Inflate the tires a bit
If we look at bad tire conditions in this manner, what common tire issue is the technician resolving? Based on our previous list, your mechanic is able to help you when the tires are experiencing patchy, one-sided, or cupped wear.
Still, keep in mind, if the tires are not usable anymore, do NOT drive on them.
Investing in new tires will be cheaper than wrecking the car because of bad tires. In the long run, they will save you from headache, injury, and car damage.
Other Frequent Tire Issues
Unfortunately, tread wear issues are not the only problems drivers have to deal with. There are multiple and often hazardous tire problems that cannot be prevented. Here are a couple of them drivers should keep in mind, as regular tire maintenance can help prevent some of them.
What Causes Tire Chunking?
Tread chunking, also known as pitted tires, is often caused by using tires off-road. Unpaved roads can take chunks out of tire tread with their uneven and often rocky surfaces. This results in chunks missing from tire tread.
Other tire chunking causes include aggressive driving, improper tire alignment, incorrect tire pressure levels, overloading the tires, and using old or worn tires. Sadly, tires chunking is a sign that they will not last much longer.
Is Tire Chunking Dangerous?
Yes, chunking tires are a serious road hazard issue. Even just one chunk missing from the tire tread can lead to a tire ripping apart (tire blowout), which often results in accidents. Therefore, when you notice the tire chipping or tire pitting (as it is also known) on your tires, you should start looking for a new tire set.
Split Tire Sidewall
Tire sidewall separation, also known as tire bubbles, is not a tread wear issue, but they are still serious. They reduce the tire's sidewall strength, which can lead to tire blowouts.
Other sidewall issues worth mentioning are the tire cords showing through the sidewall and torque cracking tires. The first one is usually caused by overusing the tires, while the second one happens to overloaded tires (when the sidewalls crack).
What Causes a Tire to Split on the Side?
There are numerous reasons for tire tread separation from sidewall. The most common one is the tire drying out. When the oils dry out of the tire, often due to constant UV light exposure, they break down the compounds and weaken the rubber flexibility. This leads to the sidewall separating from the internal tire cords, resulting in sidewall bubbles.
How to Read Tire Tread Wear?
Learning to read tire tread wear will help prevent tire problems. There are multiple ways to read the tread depth on tires. The most accurate manner is using a tread depth gauge. However, if you don't have access to one, the penny test (using Lincoln's head on a penny) is a good alternative.
Tire condition, mainly the tread life left on the footprint, determines how long a tire can be used. Knowing when to replace tires is a crucial skill all drivers should know. Check our blog post about it, along with our tire wear indicator chart to learn more.
Frequently Asked Questions (FAQs)
How do You Read a Tire Wear Indicator?
To read the tire wear indicator, turn the wheel so you can see the entire tread of the tire. Since tread indicators are located at 2/32nds of an inch, as long as the tread does not reach that point it is still usable. However, some states require more tread on the tires for them to be legally used.
What Depth are Wear Bars on Tires?
Wear bars on the tires are located at 2/32nds of an inch. The tread life of tires is measured in 32nds of an inch. For a passenger car tire that means about 20% tread life is left on the tire when it reaches these bars, as they usually start at 10-11/32nds - depending on the tire size.
What Is Secondary Rubber on Tires?
The secondary rubber is located under the primary tread of the tires. In other words, they are the sub-tread located under the tire's tread pattern. Usually, the tire secondary rubber does not offer the same traction as it is used to strengthen the tire and its performance.
How do You Evaluate Tire Wear?
There are different ways to evaluate tire wear. If you do not have a tread gauge handy at home and don't wish to purchase one, the penny test might be the best solution for you.