How to know if a tire is good


How to Check Tire Tread Depth: The Penny Test

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.

THE PENNY TEST

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.

    OTHER WAYS TO CHECK TIRE TREAD

    TREAD DEPTH GAUGE

    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.

    TREAD WEAR INDICATOR BARS

    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.

    DON'T WAIT UNTIL IT'S TOO LATE

    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.

    Tire Tread Depth | Firestone Complete Auto Care

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    With this easy test, a penny can buy you peace of mind when it comes to your tires and safety.

    Place a penny head first into several tread grooves across the tire. If you always see the top of Lincoln’s head, your treads are shallow and worn. If this is the case, your tires need to be replaced.

    If part of Lincoln’s head is always covered by the tread, you have more than 2/32 of an inch of tread depth remaining. This means you probably don’t need new tires.

    Why Worry About Tread Wear?

    The most important reason to worry about tread wear is safety.

    When your tire treads are worn, your car may respond poorly in adverse weather conditions like rain and snow. With good treads, your car will grip the road better. Also, having insufficient tread is considered illegal in many states. And finally, worn treads can make other parts of your car wear prematurely.

    Potential Problem Areas:

    1. Excessive wear in center tread indicates over inflation of the tire.
    2. Excessive wear on shoulders may signal problems such as under inflation of the tire.
    3. Uneven tread wear indicates poor wheel alignment.
    4. Excessive wear on one side of the tire signals incorrect camber angle.
    5. If the treads on the outer section become knobby, it may signal problems with the toe-in value.

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    How to check used tires and tire wear, checking wheels when buying a car

    We have already written how to check the geometry of the body, generator, ignition system, battery, engine, running gear when inspecting a used car. In this article we will tell you how to check the tires when buying a used car.

    Some experts say that using used tires is like playing Russian roulette - you only have to rely on luck. And to make the case really happy, you should check the wheels as carefully as possible.

    Contents

    • How to check tires when inspecting a car
    • Year of manufacture of rubber
    • Tire wear
    • Tread depth
    • Traces of repair
    • Coupling edge wear
    • Presence of microcracks
    • Cuts and repair marks on tire
    • Buying a car with winter tires
    • Used vehicle check with Autocode

    How to check tires when inspecting a car

    Tires are a guarantee of safety on the road. When inspecting a car and used tires, check the following:

    • year of manufacture of rubber;
    • tire wear;
    • tread depth;
    • traces of tread repair;
    • the degree of wear of the coupling edges;
    • the presence of microcracks;
    • cuts and traces of tire repair.

    Each of the parameters is important in its own way, and therefore ignoring at least one of them can significantly reduce the level of safety on the road.

    Year of manufacture of rubber

    We recommend checking first. If the tires have served their allotted time, further operation does not seem rational. This is easy to do - the date consists of two digits: the week number and year of issue, applied to the outside of the rubber. If, upon inspection of the machine, it is found that the numbers on each wheel are different, then this indicates a non-simultaneous replacement of the wheels. The reason for the replacement, if the service life has not yet come up, you should ask the seller.

    Tire wear

    Visual inspection is sufficient to check tire wear. It is important that tire wear (if any) is uniform over the entire circumference of the wheel. Uneven tire wear can be a sign of wheel imbalance, and it also indicates a possible sloppy driving style of the previous owner, which can cause several more problems when operating a car. Increased wear on the outside indicates insufficient tire pressure, which should also be checked before a test drive. The operation of such wheels is fraught with the fact that in corners the rubber will not “hold” the road well. If the center part was more subject to wear, get ready for a decrease in acceleration, handling and braking.

    Tread depth

    When buying a car, be sure to pay attention to this parameter. Tests show that the permissible tread depth should be at least half of the original - for summer tires it is at least 3 mm (1.6 mm by law, but it would be better to leave a margin), for winter tires - at least 4 mm. It is not difficult to check the depth - in car dealerships you can buy a special probe with marks or use a simple ruler.

    Traces of repair

    When inspecting the tread, it is not superfluous to check for signs of repair from the inside (on a smooth surface). By themselves, the patches on the tread are not critical, but only if their number does not exceed a couple of pieces per wheel, and their size is a third of the width of the pattern. Otherwise, the operation of the "horse" on such wheels should be abandoned. Pay attention to the nature of the patch - the restored tread pattern (the so-called "grooving") can result in a tire rupture.

    Coupling edge wear

    The tire grips the road surface across the entire tread width. The edges of the tire also have an impact on braking performance. The smaller they become, the less grip the rubber has on the road surface, and therefore the risk of driving on wet or slippery surfaces increases. A worn leading edge indicates problems with the car's suspension, which is also worth paying attention to. You can check this part of the tread "by touch" - the problem is present if the teeth on the tread edges differ in sharpness.

    Presence of micro cracks

    Tire micro cracks can occur even under conditions of minimal rubber wear and careful storage. The average service life of rubber is 5 years, but, as a rule, by the end of the term, the tire naturally becomes unusable. In the presence of small cracks, it is not recommended to exceed the speed of more than 80 kilometers per hour, otherwise the chances of complete tire wear increase rapidly. Deep cracks appear with a large degree of delamination of the tire. The use of such tires is highly discouraged.

    Tire cuts and repair marks

    Defects in the form of cuts and repair marks are a clear signal to stay away from the selected used rubber. As a rule, tire side cuts are dangerous due to the fact that the repair of such defects is extremely difficult and not gives a further guarantee of the quality of rubber operation. But, in addition, it is necessary to check and make sure that there are no hidden damages. Deformation of the tire carcass in the form of dents and creases can be the result of driving or parking on a flat tire, as well as a strong impact. The end of the service life in this case may come earlier than expected.

    The internal delamination of the tire is extremely difficult to detect. A warning can be various types of swelling on the inside of the tire. Visible breaks in the layer are also possible. Check the degree of puncture of the tire - when pressed with two thumbs, the tire should not deform much, but will quickly return to its original shape.

    These tire and wheel test parameters apply to both summer and winter tires. But, in the cold season, when the car is “reshod” in winter tires, some other factors should be taken into account.

    Buying a car with winter tires

    In winter, buying a car with winter tires is considered correct, but another situation is possible, so do not neglect the inspection of the wheels. First of all, you should check what the car is “shod” in - it can be idle for a long time, especially if the transaction takes place in the car market. Winter wheels are divided into two types: studded and friction.

      • Studded tires are distinguished by the presence of studs. The presence of all or the vast majority of studs is considered ideal and guarantees good grip on the road, and, as a result, road safety.
      • Friction tire is available without studs. Its difference from studded is a special composition of rubber, which has grip with the road surface like Velcro. This type is more suitable for the urban environment.

    Equally important is the tread depth. For 100%, it is customary to take the tread depth of new tires, 0% - unusable, respectively. The minimum permitted tread depth for winter tires is 4 mm, otherwise 0%. From the factory, tires are produced with different depths. Keep in mind that if the initial depth reached 8 mm, then 4 mm is not 50% wear, as some sellers say.

    Checking a used car with Autocode

    A buyer's vigilance will be a guarantee of a good deal. Bad tires in the general good condition of the car is not always a reason to refuse a purchase. If the wear is natural and even, and also corresponds to the average life of tires, the option of purchasing a car is worth considering. You can always eventually replace the rubber with one that will inspire confidence.

    In order to avoid doubts about the history of the purchased car during the inspection, check the history of the car using the Autocode online service. To obtain a complete report, only the VIN, chassis number or state number of the vehicle of interest is required.

    By driving in unique car numbers, you will receive the following data:

    • year of manufacture;
    • number of owners;
    • true car mileage;
    • participation of a car in an accident and an indication of the most damaged parts;
    • finding the car under the security of the bank;
    • using a car in a taxi;
    • repair work.

    If you are a professional car dealer, you can also use the Autocode Profi service of unlimited car checks. Autocode Profi allows you to quickly check a large number of cars, add comments to reports, create your own lists of liquid vehicles, quickly compare options and store vehicle data in an orderly manner.

    Tire wear or other negative factors may be hidden by the seller. So that they do not subsequently lead to problems in other parts of the machine, order an on-site Autocode check. The specialist will arrive at the place at any time and conduct a professional inspection of the vehicle. Checking the machine through Autocode will help to verify the correctness of your assumptions or refute them.

    If there are no serious problems in the history and technical part of the car and you decide to buy, take the final step - enter the seller's passport data through the car owner verification service. This service will show whether he has problems with the law, whether his passport is valid, whether there are debts and enforcement proceedings. If the audit finds serious problems, it is better to refuse the deal. View sample report

    How to check used tires and tire wear, check wheels when buying a car

    We have already written how to check the geometry of the body, generator, ignition system, battery, engine, running gear when inspecting a used car. In this article we will tell you how to check the tires when buying a used car.

    Some experts say that using used tires is like playing Russian roulette - you only have to rely on luck. And to make the case really happy, you should check the wheels as carefully as possible.

    Contents

    • How to check tires when inspecting a car
    • Year of manufacture of rubber
    • Tire wear
    • Tread depth
    • Traces of repair
    • Coupling edge wear
    • Presence of microcracks
    • Cuts and repair marks on tire
    • Buying a car with winter tires
    • Used vehicle check with Autocode

    How to check tires when inspecting a car

    Tires are a guarantee of safety on the road. When inspecting a car and used tires, check the following:

    • year of manufacture of rubber;
    • tire wear;
    • tread depth;
    • traces of tread repair;
    • the degree of wear of the coupling edges;
    • the presence of microcracks;
    • cuts and traces of tire repair.

    Each of the parameters is important in its own way, and therefore ignoring at least one of them can significantly reduce the level of safety on the road.

    Year of manufacture of rubber

    We recommend checking first. If the tires have served their allotted time, further operation does not seem rational. This is easy to do - the date consists of two digits: the week number and year of issue, applied to the outside of the rubber. If, upon inspection of the machine, it is found that the numbers on each wheel are different, then this indicates a non-simultaneous replacement of the wheels. The reason for the replacement, if the service life has not yet come up, you should ask the seller.

    Tire wear

    Visual inspection is sufficient to check tire wear. It is important that tire wear (if any) is uniform over the entire circumference of the wheel. Uneven tire wear can be a sign of wheel imbalance, and it also indicates a possible sloppy driving style of the previous owner, which can cause several more problems when operating a car. Increased wear on the outside indicates insufficient tire pressure, which should also be checked before a test drive. The operation of such wheels is fraught with the fact that in corners the rubber will not “hold” the road well. If the center part was more subject to wear, get ready for a decrease in acceleration, handling and braking.

    Tread depth

    When buying a car, be sure to pay attention to this parameter. Tests show that the permissible tread depth should be at least half of the original - for summer tires it is at least 3 mm (1.6 mm by law, but it would be better to leave a margin), for winter tires - at least 4 mm. It is not difficult to check the depth - in car dealerships you can buy a special probe with marks or use a simple ruler.

    Traces of repair

    When inspecting the tread, it is not superfluous to check for signs of repair from the inside (on a smooth surface). By themselves, the patches on the tread are not critical, but only if their number does not exceed a couple of pieces per wheel, and their size is a third of the width of the pattern. Otherwise, the operation of the "horse" on such wheels should be abandoned. Pay attention to the nature of the patch - the restored tread pattern (the so-called "grooving") can result in a tire rupture.

    Coupling edge wear

    The tire grips the road surface across the entire tread width. The edges of the tire also have an impact on braking performance. The smaller they become, the less grip the rubber has on the road surface, and therefore the risk of driving on wet or slippery surfaces increases. A worn leading edge indicates problems with the car's suspension, which is also worth paying attention to. You can check this part of the tread "by touch" - the problem is present if the teeth on the tread edges differ in sharpness.

    Presence of micro cracks

    Tire micro cracks can occur even under conditions of minimal rubber wear and careful storage. The average service life of rubber is 5 years, but, as a rule, by the end of the term, the tire naturally becomes unusable. In the presence of small cracks, it is not recommended to exceed the speed of more than 80 kilometers per hour, otherwise the chances of complete tire wear increase rapidly. Deep cracks appear with a large degree of delamination of the tire. The use of such tires is highly discouraged.

    Tire cuts and repair marks

    Defects in the form of cuts and repair marks are a clear signal to stay away from the selected used rubber. As a rule, tire side cuts are dangerous due to the fact that the repair of such defects is extremely difficult and not gives a further guarantee of the quality of rubber operation. But, in addition, it is necessary to check and make sure that there are no hidden damages. Deformation of the tire carcass in the form of dents and creases can be the result of driving or parking on a flat tire, as well as a strong impact. The end of the service life in this case may come earlier than expected.

    The internal delamination of the tire is extremely difficult to detect. A warning can be various types of swelling on the inside of the tire. Visible breaks in the layer are also possible. Check the degree of puncture of the tire - when pressed with two thumbs, the tire should not deform much, but will quickly return to its original shape.

    These tire and wheel test parameters apply to both summer and winter tires. But, in the cold season, when the car is “reshod” in winter tires, some other factors should be taken into account.

    Buying a car with winter tires

    In winter, buying a car with winter tires is considered correct, but another situation is possible, so do not neglect the inspection of the wheels. First of all, you should check what the car is “shod” in - it can be idle for a long time, especially if the transaction takes place in the car market. Winter wheels are divided into two types: studded and friction.

      • Studded tires are distinguished by the presence of studs. The presence of all or the vast majority of studs is considered ideal and guarantees good grip on the road, and, as a result, road safety.
      • Friction tire is available without studs. Its difference from studded is a special composition of rubber, which has grip with the road surface like Velcro. This type is more suitable for the urban environment.

    Equally important is the tread depth. For 100%, it is customary to take the tread depth of new tires, 0% - unusable, respectively. The minimum permitted tread depth for winter tires is 4 mm, otherwise 0%. From the factory, tires are produced with different depths. Keep in mind that if the initial depth reached 8 mm, then 4 mm is not 50% wear, as some sellers say.

    Checking a used car with Autocode

    A buyer's vigilance will be a guarantee of a good deal. Bad tires in the general good condition of the car is not always a reason to refuse a purchase. If the wear is natural and even, and also corresponds to the average life of tires, the option of purchasing a car is worth considering. You can always eventually replace the rubber with one that will inspire confidence.

    In order to avoid doubts about the history of the purchased car during the inspection, check the history of the car using the Autocode online service. To obtain a complete report, only the VIN, chassis number or state number of the vehicle of interest is required.

    By driving in unique car numbers, you will receive the following data:

    • year of manufacture;
    • number of owners;
    • true car mileage;
    • participation of a car in an accident and an indication of the most damaged parts;
    • finding the car under the security of the bank;
    • using a car in a taxi;
    • repair work.

    If you are a professional car dealer, you can also use the Autocode Profi service of unlimited car checks. Autocode Profi allows you to quickly check a large number of cars, add comments to reports, create your own lists of liquid vehicles, quickly compare options and store vehicle data in an orderly manner.

    Tire wear or other negative factors may be hidden by the seller. So that they do not subsequently lead to problems in other parts of the machine, order an on-site Autocode check. The specialist will arrive at the place at any time and conduct a professional inspection of the vehicle. Checking the machine through Autocode will help to verify the correctness of your assumptions or refute them.

    If there are no serious problems in the history and technical part of the car and you decide to buy, take the final step - enter the seller's passport data through the car owner verification service. This service will show whether he has problems with the law, whether his passport is valid, whether there are debts and enforcement proceedings.


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