Anyone who drives a car knows what tire tread is. But do you know how to tell whether it’s wearing thin?
Worn out tires affect your car’s performance and your safety. Luckily, there’s a simple way to check your tires with just your pocket change.
A new car tire typically has a tread depth of 10⁄32 or 11⁄32 inches while a light truck will have between 11⁄32 and 19⁄32 inches. The U.S. Department of Transportation recommends that you replace your tires once they’ve worn down to 2⁄32 inches. Many states require tires to be replaced when the tread reaches that depth.
How do you know when your tires are officially worn out? You can use a tread depth gauge or take your car in for a professional evaluation. But the easiest way is to do a penny test.
Many car and truck tires come with indicator bars at 2⁄32 inch. If these are even with your tread ribs, you’ll know your tires need to be replaced.
Now you can measure your tread, but you may not know about all its components or what different tread patterns are for. The more you know about types of tread, the easier it will be for you to choose the best tires for your vehicle. Here are some facts to beef up your tire knowledge.
There are four (sometimes five) main components to tire tread:
Ribs and tread blocks make contact with the pavement, while grooves and voids channel water when roads are wet and allow the blocks to flex as tires grip the road.
Siping is designed to improve tire performance during wet and winter driving conditions.
Different tire manufacturers combine these features to create signature designs and offer good performance for a range of driving conditions.
Though each tire manufacturer makes unique variations on tire tread, the patterns generally fall into three categories. Each pattern provides different handling and performance.
Summer tires and winter tires both generally have a symmetric design, with winter tires sporting deeper tread depth and sipes. Asymmetric patterns are often a good choice for all-season tires.
Though tires are considered bald at 2⁄32 inch, they lose some of their performance capabilities before that.
As tire tread wears, it becomes less able to channel water and the risk of hydroplaning increases, especially at higher speeds.
If you know your tires are partly worn, be sure to give yourself extra stopping distance in wet conditions.
Grip loss on snowy or icy roads is a concern. As the rubber wears, sipes disappear and tread blocks don't provide as much grip. Again, allow yourself more stopping distance and consider replacing your tires to stay safe during winter months.
Tires with partly worn tread are more likely to get punctures and lose air pressure, too. And punctures can cause tire failure, which is a particular problem at high speeds because you can lose control of your vehicle.
A penny test will tell you when your tires are bald, but if you’re headed into winter or a rainy season, a tread depth gauge is the surest way to test. Or stop by your local tire shop to have a professional evaluate your tires.
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When it comes to checking tire tread, there are a number of methods that can help you know if it’s time to replace a tire.
Heavily worn tread will prevent a tire from performing as designed and can lead to unsafe driving conditions. One of the simplest, most common ways to check tread depth requires nothing more than a penny and a few moments of your time.
In the United States, tire tread depth is measured in 32nds of an inch. New tires typically come with 10/32” or 11/32” tread depths, and some truck, SUV and winter tires may have deeper tread depths than other models. The U.S. Department of Transportation recommends replacing tires when they reach 2/32”, and many states legally require tires to be replaced at this depth.
The idea of the penny test is to check whether you’ve hit the 2/32” threshold. Here’s how it works:
Place a penny between the tread ribs on your tire. A “rib” refers to the raised portion of tread that spans the circumference of your tire. Tire tread is composed of several ribs.
Turn the penny so that Lincoln’s head points down into the tread.
See if the top of his head disappears between the ribs. If it does, your tread is still above 2/32” , If you can see his entire head, it may be time to replace the tire because your tread is no longer deep enough.
When performing the penny tire test, remember not only to check each tire, but to check various places around each tire. Pay special attention to areas that look the most worn. Even if parts of your tread are deeper than 2/32”, you should still replace the tire when any areas fail the penny test.
Consistent wear around the whole tire is normal, but uneven tread wear could be a sign of improper inflation, wheel misalignment, or a variety of other things. If you see uneven tread wear, you should have a technician inspect your vehicle.
A simple way to check your tire tread depth is by using a tread depth gauge. You can find tire tread depth gauges at your local auto parts store. There are many models available, but an inexpensive simple graduated probe gauge will work just fine.
All you have to do is stick the probe into a groove in the tread and press the shoulders of the probe flat against the tread block and read the result. All gauges should measure in both 32nds of an inch and millimeters.
Another indicator of worn out tread already lives in your tires themselves. Every performance, light truck, or medium commercial tire comes equipped with indicator bars (or wear bars) embedded between the tread ribs at 2/32”. They’re there to help you monitor tread depth and make decisions about tire replacement. Just look to see if the tread is flush with the indicator bars. If they are, it’s time to replace the tire.
While the penny tire test does deliver on what it promises – indicating whether tread has reached the legal limit – it may not be the best indicator of whether your tires are safe for the road. Tire performance can diminish significantly before your tread hits 2/32”. Even though the law deems fit for safe driving may not prevent you from hydroplaning or losing control in rainy, slushy conditions.
If you think your tires may be close to needing replacement, have them checked out by a licensed mechanic.
Proper operation of the car includes monitoring the condition of the tread. Gradually, tires wear out, wear out under the influence of constant loads. Branded tires last longer, original tires for mini tractors are made in compliance with the most stringent quality standards. As practice shows, with proper operation, it will last the declared period.
The average life of tires is 5-7 years. Rubber lasts this long only if it is fully cared for and properly exploited. Often, the owners neglect the elementary rules for care, which greatly reduces the life of the tires. Much depends on the state of the suspension system, as well as on the driving style. Under extreme use, the tread wears out much faster.
The easiest way to determine how much tread is left is to use a caliper.
This tool has a depth gauge, with which you can carry out all studies with an accuracy of tenths of a millimeter. First you need to deal with the scale, the exact data look in the field located below the main values.
The measurement algorithm is as follows:
The resulting value indicates the remaining tread depth of the wheel. On the classical scale, we count tenths of a millimeter and add them to the main figure. In this case, the most convenient models with an electronic display.
There is a special tool for monitoring residual tread - it is used at stations, factories and other facilities.
With it, you can accurately calculate the values by determining the height of the rubber. If you plan to often carry out such procedures, it is better to buy your own tool. In other cases, you can visit a service station and use this service.
The most reliable information can be obtained by measuring several wheels, preferably in 2-3 places. So it will be possible to recognize uneven wear, the cause of which may be incorrect wheel alignment or other suspension failures.
If you do not have a specialized tool at hand, you can also resort to this method. But here accuracy suffers and you will get only approximate values, without tenths of a millimeter. This option is suitable for a superficial assessment; when obtaining boundary or lower values, it is worth checking with a tool designed for such tasks.
The ruler should be narrower than the tread grooves so that it can be conveniently placed.
Dirt and debris must be cleaned from the hole, as this may affect the accuracy of measurements. The tool is placed up to the stop and the residual depth is observed on the scale.
In this version, a 10 kopeck coin is used: it is placed in a groove on the side with the inscription "10 kopecks". If the name is visible, then the protector is badly worn and must be replaced. To obtain more reliable information, it is advisable to use measuring instruments. The most accessible and accurate measurement method is the use of a caliper.
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Tire wear in the United States is checked using a coin with the image of the first president of the country. A one-dollar coin is inserted into the groove of the tread with Washington's head down. If Washington's hair is visible, then it's time to buy new tires. A coin with a face value of 1 cent will also help to check the wear of automobile rubber.
If the top of the Lincoln is visible, then the tires have reached the tire wear rate and must be replaced immediately.
Tire wear can also be determined with a 1 euro coin. It must be inserted into that part of the tire where the tread is most worn. If the golden circle is in rubber, then the tire will still serve you. If the gold part of the coin is completely visible, then it's time to change the shoes of your car.
Tire wear can also be determined using Russian money. The domestic 2-ruble coin must be inserted into the protector with the eagle's head down. If the top of the bird is visible above the surface of the tire, then the tire has not yet reached the end of its life.
Premature tire wear can be avoided. According to the Research Institute of the Tire Industry (NIIShP), the "life" of half of the tires is reduced due to improper operation. After all, the service life of rubber largely depends on driving style, road conditions, compliance with the load index and correct tire pressure.
Therefore, it is not surprising that with the same model of car and “shoes”, the mileage of their tires can differ by several thousand kilometers.
The main causes affecting premature tire wear
For new tires, the break-in process is important. The first 200-300 kilometers of newly purchased tires should be extremely careful, especially in winter or in rainy weather. This is due to the fact that before vulcanization, the treads of new tires are covered with a separating layer, which should be erased only during operation. Therefore, all types of rubber must be run-in.
Tire wear occurs in a variety of ways:
Therefore, the car should not stand on tires for months. Before storing the machine, it is advisable to increase the tire pressure to 3.0 bar. So you can avoid deformation of the tire Uneven tire wear is normal because the tire is subjected to uneven loads while driving. In this case, a new wheel balancing will help. In most cases, when sawtooth teeth form on the transverse grooves of the profile, it is necessary to use cruciform wheel balancing. But this will only help with the correct geometry of the axis. This will change the direction of the tire. The sawtooth teeth will gradually disappear, along with them the noise will also disappear.
If you change wheels with asymmetric tread patterns regularly every 10,000 km, uneven wear of all tires can be avoided.
But the replacement must be done on one side. That is, the front right wheel should only change to the rear right, and vice versa.
In 1992, a uniform wear rate for summer tires was established in Europe - the minimum profile depth for tires for cars, trucks and motorcycles is 1.6 mm. This requirement also applies in Russia. An exception to the rule are light wheels with a minimum tread height of 1 mm. But for wide-profile and summer tires, this rate is too small. With such a profile depth on a wet road, the tire will have poor handling. For safety reasons, summer tires should be changed already when the remaining profile depth reaches 2 mm (wide profile - 3 mm). Modern winter tires have a tread depth of 9, depending on the manufacturer.-12 mm. Permissible wear for them is 4-6 mm.
Many modern tires have built-in wear indicators in the form of small rubber pimples. They are soldered into the base of the protector. When the tire wears down to acceptable limits, the pimples become flush with the tread.
