Why Tire Inspections Are Important
Every time you climb into your car to hit the road, it is likely you don’t give a second thought to your tires. Of course, a flat tire is pretty noticeable, but if they are all filled with air and still on the vehicle, you have little reason to be suspicious. The tires are one of the most important parts of your vehicle, and are crucial to safe handling. While most drivers don’t pay attention to the tires until there is a flat or blowout, adding a tire inspection to your vehicle maintenance routine may help prevent future issues, provide maximum tire life, and could help you be certain your vehicle can be driven safely.
Why You Should Check Your Tire Tread
Your vehicle's tires really are where the rubber meets the road, so keeping them in good condition and performing visual tire inspections is essential for the safe operation of your vehicle. Checking your tires regularly helps you discern if the air pressure is too low (under-inflated) or too high (over-inflated), if there is excessive or irregular tread wear, or if there is damage to the tire tread or sidewall.
Under-Inflated Tires
The air pressure in a tire keeps the sidewall rigid and maintains the height of the tire. If the air pressure is too low, driving on a severely under-inflated or flat tire can damage the tire and may cause a blowout. This also causes the center of the tire tread to have less contact with the road, which may cause excessive wear on the outside edges of the tire tread and less control on wet or snow-covered roads. Since the air in the tires is what carries your vehicle, too little or too much air pressure can affect handling even in optimal weather conditions.
Over-Inflated Tires
High air pressure in tires will cause the tires to stand too tall. The effect this has on tread is similar to low tire pressure, except the center of the tire makes more contact than the edges. This may also cause traction issues in wet or winter weather, and creates more wear on the center of the tire tread. If your tires are over-inflated, this also results in too much rigidity in the tire, which could cause a stiff or noticeably harsher ride, and reduced handling ability.
How to Tell If Your Tires Need to be Replaced
If your tires have less than 2/32” of tire tread, it is recommended to replace them. If your tires are bald, showing belts, or have tread damage, this may be an indication that your tires need to be replaced. Depending on the severity of the tire wear or damage, you could unexpectedly experience a tire failure such as a blowout. The tread grooves and pattern of your tires also helps to direct moisture away from the contact surface of the tire. If your tires are worn and your tire tread is especially low (below 2/32”), this puts you at risk of hydroplaning in wet weather as the tire tread pattern is not deep enough to channel water away from the contact surface of the tire, resulting in a layer of water between your tire and the road. Bald tires or tires with cords or steel belts showing should be replaced as quickly as possible, as these are considered severely worn. Even newer tires with tread damage, bulging, or irregular tread wear should receive a thorough tire inspection by a tire service professional to determine whether the tire(s) should be replaced or not.
How Often Should Tires Be Inspected
You may be surprised how often you should inspect your tires, and it may vary by the time of year and where you live. No matter where you drive, you should complete a full tire inspection at least once a month, but you should check the air pressure even more often. During the spring and summer months, the tire pressure should be checked at least once every two weeks. During the fall and winter months, it is recommended you check the air pressure at least once a week. Since the spring and summer months are typically warmer, tires hold air pressure more consistently. However, during the colder months of the year, tires will likely lose air pressure. If you’d like to know more about why tire pressures are lower in winter, visit low tire pressure explained. We’ve got you covered. While these times are a good guideline for checking your tires, you may need to make a custom schedule if you notice your tires are not holding air correctly or if you notice irregular tire wear.
How To Inspect Tires
There are several items you need to check during tire inspection, and you may need to perform a full tire inspection each time depending on the quality, condition, or age of your tires.
How to Check The Air Pressure of a Tire
After removing the valve stem cap, you simply push the connector or coupler end of the gauge to open the valve stem, and remove it as soon as the gauge stops to check your reading. If you don’t already know the correct pressure for your tires, you can look for a sticker on the inside of the door post that will often provide the manufacturer’s recommended air pressures. If you have changed the size of your tires or wheels from what would have been installed from the factory, it is often best to check the tire’s sidewall or the tire manufacturer’s recommendation for the appropriate specifications. For further explanation, check out our article on how to check tire pressure.
Performing a Visual Tire Inspection
After checking the tire pressure, you can inspect the tire for anything that “doesn’t belong”, or that just doesn’t look right. Look for damage to the sidewalls, such as cracks, cuts, protruding objects, or any bulges or bumps that feel soft when pressed. Then you can inspect for items stuck in the tread or sticking out from the tire. You can remove rocks or debris from the tread, but you may want to leave in any objects such as nails or screws, as removing them could result in a more rapid air leak from the tire tread. If you leave an object in the tread that has punctured the tire, it is also easier for a tire professional to locate, inspect, and properly repair the tire if possible.
Tread Wear & How to Measure Tire Tread Depth
You should measure each channel across the tire and if any are below 2/32” the tire must be replaced. Tire tread depth is measured in 32nds of an inch, and all vehicles on the road are required to have a minimum tread depth of 2/32”. Since this is difficult to measure with the naked eye, you can either use a tread depth tool or perform the “penny test.” To measure the depth of your tire tread using a penny, turn the penny upside down with Lincoln’s head facing you. If the tread goes past the top of his head, there is still more than 2/32” of tread for you to safely drive on the tires. However, you may want to consider replacing your tires if the tread does not reach or is close to the top of his head (under 2/32”). This test should be performed across every tread channel of the tire to ensure that it is wearing evenly and that the entirety of the tire's thread is still deep enough to provide adequate traction.
Common Tire Tread Wear Patterns
While inspecting the tread depth, you should also examine the tread wear pattern. If there is more wear in the middle or on the edges of the tire, it likely points to driving with too much or too little air pressure in the tires. If the tread wear is uneven, it could mean that your vehicle’s suspension components are out of alignment, the vehicle’s braking system may be malfunctioning, or the tires were not rotated at the correct intervals. You may even notice flat spots on the tire tread or see metal cords showing through uneven tire wear, which is a clear indicator that the tire should be replaced.
When Should Tires Be Replaced?
If you notice any tire issues, you should avoid driving the vehicle and have a professional tire inspection completed as soon as possible. If the inspection determines the tire needs to be replaced, this should be done and the tire and wheel balanced before you continue to drive your vehicle. Driving on worn or damaged tires may be a safety hazard and could even lead to unsafe driving conditions or an accident. Any time you replace a tire, it is generally recommended that tires should be replaced in pairs of front or back tires, but it is often best to replace all four tires at the same time, even if they are the same age and irregular wear is not evident. Some All-Wheel-Drive vehicles may specifically require all four tires to be replaced at the same time, even if only one tire is damaged. This is because the differences in the tread height between the new tire and the worn tires cause the tires to rotate at slightly different speeds, which can cause excessive wear on the differentials in some AWD vehicles and lead to costly repair costs in the future. It is also a good idea to get your vehicle aligned and address any issues that may lead to uneven wear, including shocks and struts, tie rods, ball joints, and more when you replace your tires to ensure they last as long as possible.
We hope this helps you understand the importance of inspecting your tires and how to complete an inspection both regularly and in a timely manner. If you are unsure about the state of your tires after inspecting them, consider taking your vehicle to a tire professional and allow them to inspect the tires for you. If you need any tire maintenance tools, such as a tire pressure gauge, tread depth gauge, an air hose, tire inflator, or a portable air compressor, stop by your local O’Reilly Auto Parts and speak to a parts professional to get the right tire tools and accessories to keep you driving safely.
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