How To Fix Cracked Tires And Tire Dry Rot (And When To Replace Tires)

This article explains how to fix cracked tires and tire dry rot.

Many tire service companies and service dealerships will tell you that you need to replace a tire as soon as there’s a crack or if you see dry rot.

This isn’t always the case because sometimes it’s possible to repair cracked tires or tire dry rot.

Luckily, this is something that is straightforward enough that anyone who is willing to learn how to fix a cracked tire and knows their way around removing and reattaching tires can do.

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old tires that are cracked and worn with dry rot

How to Fix Cracked Tires (Dry Rot Tires)

Fixing cracked tires doesn’t have to be something for which you seek professional assistance. If you want to save some money and practice some new vehicle repair skills, then you could try a DIY job to restore your tires back to their former glory. There are two effective methods for fixing tires that are cracked. We will describe them below, along with the equipment needed and a step-by-step guide.

Method 1 – Seal Cracks Externally with a Protectant

Equipment Needed:

Step 1: If you have just driven or been driving your vehicle, you must first wait for the tires to cool down before you start work. While they are cooling, you can look at the outside of the tires for cracks. Take note of where the cracking has occurred, regardless of how serious. You’ll want to repair them all.

Step 2: Remove the tire from the wheel and place it on a flat and spacious work surface. You’ll need the space to work evenly and effectively, and you can’t see where all the cracking is when the tire is left on the wheel. Once again check where cracking has taken place.

Step 3: Apply the degreaser all over the tire. The degreaser should be applied evenly to the entire surface and then left for a few minutes to work.

Step 4: Now is the time to wash the tires. Unlike the method below where you focus on damaged areas more, the degreaser in this method needs to be applied all over the tire and then thoroughly washed off. You can repeat this process with sponges and rinsing water until you are satisfied the tire is completely clean.

Step 5: Finally, let the tire become completely dry and then apply the protectant to the entire surface. You should check with your auto parts supplier which protectant will work best for your particular type of tires. It may even help to show photos of the damage when buying the protectant so the seller can get a good idea of what will work.

The protectant will need at least several hours to cure, so leave the tire to cure and then inspect it once again. If anything looks amiss, you can repeat the process over. 

How To Fix Cracked Tires

Method 2 – Seal Cracks Internally with a Tire Sealant

Equipment Needed:

  • Tire pressure gauge
  • Tools for removing and reattaching the tire(s)
  • Carburetor cleaners
  • Tire crack sealant

Step 1: Ensure that the tires are cool. Do not attempt the next step immediately after driving the vehicle. Allow time for the tires to cool down first. Use this time to inspect the damage to the tire.

Step 2: Once cool, remove the tire you are working on and place it on a flat, clean work surface that allows you to see all the damage to each tire inside and out. Identify all the areas where cracks are showing so you know where you are going to have to clean and then apply your tire sealant.

Step 3: The next stage is cleaning. You need to clean the tire before you perform the sealing work. This is similar to cleaning an area of chipped or damaged paint before touching it up. You can use the carburetor cleaners to spray on the tire over the areas that will need to be repaired.

Step 4: Once all the affected areas are clean and dry, you have to apply the flex seal. Different tires require different sealant types, so if you are unsure ask your auto supplier to recommend a tire sealant. Apply the sealant as instructed on its packaging, but remember always to remove excess flex seal from the tire surface.

Step 5: Finally, you can reinflate your tires and check you have the correct pressure using the pressure gauge. You will certainly have lost some tire air during the repair process, so reinflation is essential. Reset the tires and check the pressure once again.

For both of the above methods, it’s very important that you remember not to attempt the work when the tires are still hot from friction. In addition, whether you’re using the external protectant or the internal flex seal, be sure to follow the guidelines on preparation and application as indicated by the specific product you use.

Learn more about the best tire car sealant

8 Causes of Cracked Tires and Tire Dry Rot

If you spot that your tires are cracked or have tire dry rot in them, then it’s important to be able to have some idea as to why that has happened. Below are the seven biggest causes of cracked tires and tire dry rot:

  1. Extended inactivity – car sits idle for a long period of time
  2. Natural rubber degradation
  3. Exposure to sunlight
  4. Ozone
  5. Improper care and maintenance
  6. Low-quality tires
  7. Extreme shifts in temperature

1. Long-time inactivity

Tires are manufactured to be used regularly. A long period of sitting idle can cause the resins, antioxidants and other protective chemicals in the tire rubber to evaporate and lose their protective power. This is especially true when the vehicle has been left outdoors. As these materials evaporate, the tire naturally starts to dry and the tire eventually starts to crack. The fact is that the same thing will happen when you use the tires, with protective elements being transferred to the road, but it happens faster when the tires are idling.

You need to be especially careful with the tires on occasional vehicles such as camper vans, classic cars, trailers, motorhomes and others that you don’t necessarily use as part of your everyday driving. These are left idle for the longest periods and so are at the greatest risk of cracking due to inactivity.

2. Natural rubber degradation

As we touched on above, the rubber in your tires is not impervious to harm and degradation when you are using it regularly or not. Due to the various conditions that you put the rubber through, and over the natural course of its life, the rubber will simply start to degrade. Tire cracking and tire dry rot are the natural results of these processes.

Besides the natural wear and tear of everyday use, there are also common impacts like bumping into the curb for example, which also serves to weaken the tire wall and leave it more vulnerable to things like cracking and tire dry rot.

3. Exposure to sunlight

The sun’s UV rays are the enemy of just about every part of your car. You might have thought that it was just the car’s paint that was at risk, but actually, your vehicle’s dashboard, electronics, fabric and leather upholstery, and your tire rubber are all negatively impacted by that ultraviolent radiation. A combination of these UV rays and the heat cause the rubber to quickly dry and degrade.

The climate, in general, has a huge impact on the health of your tires. The National Highway Traffic Safety Administration (NHTSA) did detailed research that showed a clear connection between higher temperatures and faster onset of tire cracking and tire dry rot. The site safercar.gov said that exposure to high temperatures “can accelerate the tire ageing process, which could contribute to tire failures…”

4. Ozone

Another dangerous substance that is no friend to your tire rubber is ozone. You might wonder how ozone in the atmosphere would impact tires on the ground, but that’s not the source of the ozone that’s damaging your vehicle tires. Cracking and tire dry rot can be caused by ozone that leaks from various kinds of electronic equipment and machinery that might be in close proximity to your cars.

This is actually how many tires in storage with tire sellers come to get cracked and rotting because these facilities are frequently auto garages and service centers where there is a large amount of static-emitting electronics that generate ozone. This type of cracking is often specifically referred to as “ozone cracking.”

5. Improper care

Finally, the other chief cause of tire cracking and tire dry rot is simply not taking proper care of your tires. Using harsh chemicals to clean them faster, for example, is a good way to degrade the rubber more rapidly. Equally, driving without care and damaging the tire sidewalls by driving up onto high curbs, not maintaining the correct tire inflation with pressure either low tire pressure or high tire pressure, overloading your car and creating too much load on the tires — all can contribute to faster degradation. Don’t forget that underinflated tires can contribute to various problems when driving.

6. Low-quality tires

Your budget might limit how much you can afford to pay for tires but just know that a less expensive tire can also mean that you are buying a lower quality tire that may not wear as well as a more expensive tire. In the case of tires, paying for a good quality tire can help with tire longevity, assuming that you’re doing the proper maintenance and care.

7. Weather – Extreme temperature shifts and humidity

Some parts of the country see wide variances in temperature and this can sometimes happen in a short period of time, which isn’t good for rubber. Just as heat and high UV light can contribute to dry rot and cracks.

3 Signs of Cracked Tires and Tire Dry Rot

If you’re not sure whether your car tires are exhibiting cracking or tire dry rot, take a closer look at the tires and look for the following three signs:

  1. Look of cracked leather or elephant skin
  2. Discoloration in the rubber
  3. Brittle and rigid texture

1. A look of cracked leather or elephant skin

If you’ve ever seen old leather or the cracked hide of an elephant before, you’ll know what to look for in your tire. The dried-out, crack-filled surface is unmistakable. It might not cover the entire surface but instead, be focused on particular areas.

2. Discoloration in the rubber

Tire rubber that has become subject to tire dry rot and cracking is typically a lighter color than the rest of the tire. It will appear greyer and should stand out quite clearly from the healthier, darker black of the rest of the tire surface.

3. Brittle and rigid texture

Finally, one more sign you can get of cracking and tire dry rot is to run your hands over the tires and feel how the texture has changed. Cracked tires are more rigid and feel brittle to the touch like if you applied some pressure the tire would start to flake away.

5 Tips for How To Prevent Dry Rot And Cracked Tires

As with all problems in cars, the best way to fix them is to do your best to prevent them altogether.

Here are five ways that you can do just that:

  1. Buy high-quality tires
  2. Drive regularly
  3. Keep the car out of the sun
  4. Check tire inflation levels regularly
  5. Use kinder products on your tires

1. Buy high-quality tires

The first thing you can do is invest in top-notch tires when it comes time to switch them out. The average set of tires should last from 6 to 10 years, but you can get to the higher end of that when you look to higher-end brands with better-quality rubber. They will cost more, but they will be more resistant to wear and tear and, most importantly, resistant to cracking and tire dry rot.

2. Drive regularly

Don’t leave your vehicle sitting idle and unused for long periods of time. Take the car out to “exercise” the rubber, which helps to keep it pliant and its protective resins and other elements active. Even a short drive will do. If you plan to take an extended vacation, then ask a friend, neighbor or another family member to look in on the car and take it out for a quick drive around the neighborhood just keep the tires active. Think of it as asking someone to water your plants. It’s the same principle.

3. Keep the car out of the sun

Regardless of what quality of tires you possess, keeping them from sitting in the sun for long periods is a crucial part of keeping them from cracking or suffering dry rot. The UV radiation will affect all manner of tires sooner or later. If you have a garage, keep the car in there when you’re not using it. It’ll help keep the tires cool as well as sheltered from UV. Saving that, you could use a car port or car cover.

The fact is that both temperature extremes, hot and cold, have detrimental effects on our tires. If you live in a place with either long hot periods or harsh winters, then ensure to take big steps to keep the vehicle sheltered from the harshest parts of those extremes.

4. Check tire inflation regularly

The NHTSA did a study in which they found that about 12 percent of all passenger vehicles had at least one tire that was underinflated. Overinflation can be damaging, too, so you should take steps to ensure that your tires are always properly inflated. Use your owner’s manual to determine the optimum psi rating for your tires and keep them at that level. If your vehicle is new, don’t ignore warnings from the tire pressure monitoring system.

5. Use kinder products to clean your tires

Finally, to avoid the ravages of harsh cleaning chemicals, ask your auto parts supplier about tire cleaning products that are effective but also gentler on the rubber. These are usually better for the environment, anyway. The best products are usually those that are non-petroleum based.

When is dry rot or cracked tires too bad to repair?

There are signs that it’s time to replace your tires, not just repair them

  1. Missing sections of tread (chunking or chunked tires)
  2. Bulges and bumps
  3. Cracks on the sidewall
  4. Tread separation
  5. Discolored rubber

Missing sections of tread (chunking or chunked tires)

When your tire is missing sections of tread, it’s time to replace it. Chunking is a term that’s often used to describe when a tire is missing sections or large pieces as if someone cut it off.

Bulges and bumps

Bulges and bumps suggest that the lining of the tire has been damaged and if that is the case, it’s likely time to replace the tire.

Cracks on the sidewall

Cracks on the sidewall can be an early indication of bigger problems. If they’re thin cracks, they won’t be a problem but if they’re thicker or widespread or you have several, then look at replacing the tire, not just repairing it.

Tread Separation

Tread separation happens when the tire separates from the casing of the tire. This is typically an indication of a manufacturing defect.

Discolored rubber

If the rubber is discolored, this is an indication that the tire is losing its durability and it’s likely a good idea to replace it.

What Does Tire Dry Rot Look Like?

The appearance of tire dry rot is unmistakable. This is a tire that looks as though the life force has been drained from it. In this case, that life force is the protective resin and other compounds that keep it looking healthy. Besides the cracks, dry rot involves quite an extreme drying out and discoloration of the tire surface. You’ll notice a look of cracked leather or elephant hide when you look at the tire rubber. When you look for signs of dry rot, be sure to look closely because it often starts in just small areas that then grow into larger affected areas.

FAQs

When is dry rot on tires dangerous? When are cracks in tire treads unsafe?

Dry rot and cracks on tire treads are unsafe as soon as it starts. Tire dry rot causes the rubber to lose its flexibility and crack gradually becoming more and more brittle which leads to sidewall damage. Tread might start to separate. It’s a good idea to replace tires as soon as dry rot begins so you prevent blowouts and potential loss of vehicle control.

Should dry rotted tires be replaced?

Dry rotted tires should be replaced when there’s discoloration of the rubber, tread separation, missing pieces of tire, cracks on the sidewall or bulges/bumps.

Are dry rot tires covered by warranty?

Dry rot tires are not usually covered by a warranty.

Summary

Hopefully, you’ve learned enough about fixing cracked tires and dry rot to help you make an informed decision about whether to replace a tire or repair it yourself.

Remember, many tire service companies and service dealerships will tell you that you need to replace a tire as soon as there’s a crack or if you see dry rot.

This isn’t always the case because sometimes it’s possible to repair cracked tires or tire dry rot.

Luckily, this is something that is straightforward enough that anyone who is willing to learn and knows their way around removing and reattaching tires can do.

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