As a long-time vehicle owner, you understand the importance of replacing your tires when they become too worn out to provide adequate traction. But your tires can become compromised even before they begin to bald. One of the most common reasons tires may wear out prematurely is the development of dry rot.
What Is Tire Dry Rot?
Unlike dry rot that may affect the wood in your home, tire dry rot is not caused by an organic growth and can’t spread from one tire to another. The term dry rot is used to describe a specific type of tire decay that can occur as a tire ages or is regularly exposed to harmful substances and conditions. We’ll discuss what this type of decay looks like in the next section.
Once dry rot appears in a tire, you only have a short period of time to attempt to repair the damage before the tires become unsafe for driving. Minor dry rot can be addressed by a professional using a tire sealant.
Tires with advanced dry rot must be replaced. Dry rot allows air to escape the tire, making it difficult or even impossible to keep the tire properly inflated. Dry rot can also cause unnatural rubber expansion while driving that actually breaks the tire apart. Tires with dry rot are much more likely to develop leaks, holes, and blow outs. In extreme cases, the tread may separate from the rest of the tire entirely.
What Does Dry Rot Look Like?
Tire dry rot is also known as sidewall cracking. As the term suggests, dry rot is primarily characterized by cracks in the tire rubber. If one or more of your tires has developed dry rot, you may notice the following warning signs:
These cracks can affect your car’s handling, even if your tread still has adequate depth overall.Inspect your tires for signs of dry rot at least once a year. Plan to inspect your tires in the early spring or early fall since winter and summer conditions can contribute to the development of dry rot.
If you notice signs of dry rot, have your tires evaluated by a tire and wheels professional to determine whether or not your tires are safe to drive with.
What Causes Dry Rot?
Because dry rot cannot be repaired, it’s important to reduce your tires’ risk of developing cracks.
The first step to preventing dry rot is to invest in new, high-quality tires each time you replace older tires. These tires are less likely to develop premature dry rot.
To protect your tires over time, pay attention to the substances and conditions your tires are exposed to. Avoid the following:
To keep your tires healthy, park your vehicle out of direct sunlight in an area with mild temperatures whenever possible. If you park in a garage, keep chemical solutions, heaters, and electrical equipment away from your car.
If you park outdoors, pay attention to the weather.
You may want to cover your entire car or use tire covers to minimize the effects of temperature fluctuations.
As you travel, leave your car in parking garages or in underground parking as often as possible rather than parking on a curb.
For cars that are driven infrequently, such as seasonal vehicles, RVs, and antique cars, follow the guidelines found in our previous blog, “How to Take Care of a Car That Is Rarely Driven.”
Use this information to ensure that when you get in your car, you know your tires can handle taking you wherever the road ahead may lead.
Have your tires succumbed to dry rot? Find high-quality tires that are perfect for your vehicle type at Evans Tire & Service Centers.
Posted by Benjamin Jerew Know How
In 2022, over 342 million passenger tires were shipped in the United States, according to the U.
S. Tire Manufacturers Association. Given that Americans drive over three trillion miles every year, according to the Department of Transportation, those millions of tires are needed to replace worn, damaged, aged or dry-rotted tires. When considering tire replacement for your vehicle, whether they’re winter tires that have been in storage or tires you got from a friend, it’s important to know how to tell if tires are dry rotted. If a tire dry rots, tire components, such as the tread, sidewalls, belts or bead wire, may separate from each other. Tread separation or sidewall blowout at highway speeds could result in a crash. Here’s how to determine if your tires are safe to drive on.
Tires age as soon as they’re manufactured, ideally lasting up to 10 years, but shipping, handling and exposure accelerate aging and dry rot, shortening their life. Dry rot itself is a condition that affects the material that the tire itself is made of, so it isn’t a foreign substance that can be removed like mold.
Obviously age is a major factor for dry rot in tires and cannot be mitigated, but exposure to ultraviolet (UV) light can also dry rot tires. Sunlight (especially if you live in a place with warm weather) is a common cause of tire sidewall dry rot damage. If you ever drive by an RV camp ground you will notice many vehicles with special covers over the tires to help reduce UV tire damage.
While not a direct cause of dry rot on tire materials, a lack of tire maintenance can speed up tire failure. Driving on underinflated tires causes more wear on the tire tread and more flex in the tire side wall. This leads to heat that damages the tire and may speed up tire failure. Hauling too much weight can also damage a tire, so pay attention to tire load ratings. Pushing tires over their limits combined with dry rot will greatly shorten tire life.
A close look at your tires will help you determine whether they’re safe for service or ready for recycling.
Cracks on the surface of the rubber, whether on the tread, shoulder or sidewall areas, are a good sign your tires are ready for recycling. These surface cracks are an indication that your tires have deeper cracks you can’t see, such as where the tread or sidewalls bond to the belts. The top layer of rubber will likely be hard but brittle. If any pieces of the tire crumble or fall off it is a sure sign that dry rot has set it and the tire must be removed from service immediately. Color can also be affected by dry rot so if the tire looks more grey than black it may be dry rotted.
Another factor is the DOT code, an alphanumeric string that’s usually eight or twelve digits long, molded into the tire sidewall. A valid DOT (Department of Transportation) code means the tire meets DOT safety standards. The DOT code or tire identification number (TIN) looks something like this: DOT PCTS PWPY or DOT PCTS OMFR PWPY. Here’s what each section of the code means:
For example, if the DOT code reads DOT U2LL 5117, the tire was made by Sumitomo Rubber Industries, Japan (U2), size 245/50R16 (LL), in the 51st week (51) of the year 2017 (17). Those last four digits are the most important piece of information. Even if you bought a set of tires brand new, they may have sat in a warehouse for months or longer. Most manufacturers don’t recommend using tires that are over six years old, so these tires should be discarded after 2023, even if you can’t see any cracks. Just because a tire looks fine, the age of the tire has the final say as to whether it is still safe to use. Cars that are rarely driven (like collectible cars) can have tires that look perfect thanks to routine cleaning and treatment, but are not safe to drive with on the streets.
Tread wear is another reason to replace your tires. You might have heard that you can use a coin to gauge tread depth, but nothing beats a compact and easy-to-use tire tread depth gauge. Measure all the main grooves across the tread, but not on the tread wear indicators, which are 2/32″ shallower. If any measurement is below 4/32″, wet braking and snow traction are significantly impaired. At 2/32″ tread depth, wet braking distance can be nearly double that of a new tire.
Inspect tires at least monthly for pressure, age, tread wear and dry rot. Consult your local, trusted mechanic at your next oil change or during seasonal maintenance for a professional recommendation. Lastly there is no way to fix tire dry rot. Once the tire starts to deteriorate there are no magic sprays or treatments that can bring it back. The only solution for a tire that is affected by dry rot is replacement.
Check out all the tire and wheel products available on NAPAOnline or trust one of our 17,000 NAPA AutoCare locations for routine maintenance and repairs.
For more information on dry-rotted tires and maintaining your car tires, chat with a knowledgeable expert at your local NAPA Auto Parts store.
Photo courtesy of Flickr.
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tire blowout, tire care, tire maintenance, tire tread depth, tire wear, tires, when to replace tires
Ben has been taking things apart since he was 5, and putting them back together again since he was 8. After dabbling in DIY repairs at home and on the farm, he found his calling in the CGCC Automobile Repair program. After he held his ASE CMAT for 10 years, Ben decided he needed a change. Now, he writes on automotive topics across the web and around the world, including new automotive technology, transportation legislation, emissions, fuel economy and auto repair.
People often tend to evaluate the quality of tires and their condition solely by the rest of the tread layer.
Of course, this is an important indicator, but there is a problem that, hitting the tread, does not immediately show visible marks on the surface.
Cracking or "dry rot".
Most often, the causes of its appearance are the long storage of the vehicle without movement, low tire pressure, overheating and exposure to certain chemicals. When tires are carefully inspected, dry rot can be seen by the presence of small, web-like cracks.
Cracking occurs when the oils and moisture in the tire's rubber material begin to evaporate, making the rubber hard and brittle, causing the tire to break down quickly.
Simply put, tires found to be carrying dry rot should NOT be used as unsafe tires.
Although there are no tire brands that are more or less susceptible to dry rot, one should always be aware of the storage and operating conditions that contribute to its occurrence: long periods of inactivity at high temperatures, exposure to chemicals (pesticides, herbicides, etc.). These problems are most typical for agricultural machinery and its wheels.
This does not mean that agricultural tires are inherently more likely to crack.
It's just that conditions that are considered favorable for the formation of dry rot usually occur exactly where tractors and combines work.
Actions to prevent the occurrence of cracking involve simply eliminating the consequences of adverse factors with the help of elementary actions.
Proper storage
If you are storing your car for winter or just long-term storage, keep an eye on the factors that are within your control whenever possible. Do not leave the equipment under scorching direct rays for a long time, and always put it in a garage or shed whenever possible.
In winter and summer, of course, it is ideal to store cars in a room where the temperature is regulated.
Regular cleaning
Chemicals are a common occurrence in agricultural businesses and some industries. Chemicals that come into direct contact with the surface of the wheels must be washed off after each work cycle. Simply rinsing with soapy water is enough to prevent harmful compounds from penetrating further into the depths.
Pressure control
Low pressure is one of the serious threats to the good condition of tires, leading to dry rot. Under-inflated tires can develop cracks in the sidewall through which air leaks, contributing to the enlargement of the cracks and the drying of the rubber.
If the tires on your loaders do not have time to last until the tread is completely worn out, not due to exposure to chemicals or aggressive sun, but due to frequent punctures due to production features, pay attention to Tyrefill technology - filling tires with polyurethane.
The PST company has been providing this service to its customers for several years and has collected quite a lot of positive feedback and properties of the proposed composition. The tires are softer and more “springy” than ordinary solid tires, while they are not afraid of sharp objects.
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Dry rot is commonly referred to as the decay or decay of wood materials.
However, the term has been used colloquially in other areas as well, including tire wear, although the rubber on tires does not actually rot. When cracks begin to appear in the rubber of a tire, it is said to have dry rot.
Contents
A tire is said to have developed dry rot when cracks begin to appear on its rubber. The rubber is what holds the tire together. However, whether dry rot is dangerous depends on whether you can see the tire cords. The cords are what make the tire resist inflation pressure. If the cords begin to fray—in other words, if the cracks reach the cords—the car is dangerous to drive.
Therefore, replace the tire if it has cords.
Dry rot can be caused by a number of factors. One of the main reasons is excessive exposure to ultraviolet rays. One common type of UV stabilizer is called a "competitive absorber". Competitive absorbers absorb UV light instead of the sidewall of the tire and convert the UV rays into heat so that it can be dissipated. The least expensive type of competitive absorber comes in "carbon black". This is why tires usually come in black and not a unique color. Eventually, however, the UV stabilizers no longer provide protection to the tire, causing the tire to appear grey.
The other main cause of tire rot is ozone. Ozone mainly corrodes the surface of the tire, causing sidewall degradation. Because of this, tire manufacturers use protective waxes that create a "shield" on the sidewall when the tires are in motion.
