Dry Rot Tire Sidewall Cracking Chart: Can You Drive On Them?

It is without a doubt that your RV experience will be enhanced by the condition of the tires on your specific RV. If you have any doubt about your tires, you won’t be able to relax as you drive. Being relaxed is what owning an RV is all about.

You should never drive on dry rot or cracked sidewall tires. This does not mean you can’t but that you should replace them as soon as financially or location possible. You are taking a big gamble driving on tires with either dry rot or cracked sidewalls.

To learn more about dry rot and tires, just continue to read our article. It explores the subject so you have the best information possible when you are faced with this tire condition. Cracked sidewalls cannot be repaired.

Why are My Tires Cracking On The Side?


There are several sources for your tires to get dry rot or sidewall cracks. Here are the reasons:

1. Age- rubber is a natural product that will degrade over time. Being made into tires does not stop this degradation. When the rubber ages it becomes dry and brittle and that status cause little cracks to appear.

If you leave the cracks alone, they will only get worse as time goes on. The 6th year speeds up the process even though you may not have used your RV that much in the previous 5 years.

2. Lack of use- tires are made to be used. The less driving you do the easier it is for the rubber to dry out and become less flexible. This is why many people take their tires off their trailers when they are not in use.

You need to drive your vehicles more to prevent dry rot from taking place. That may be easier for some people than others.

3. UV Rays- you may have seen those RV owners with tire covers on them. Those covers are meant to keep UV rays away from the rubber. If there is contact between the both, the UV rays will help degrade your tires faster.

While people use covers and do not drive that often, they are not stopping dry rot from taking place. They are merely stopping one source from creating it. The lack of use is still in effect here.

4. Under inflated tires- the lack of air pressure will help deform your tires. The tires are made to a certain shape and to handle a certain amount of air pressure inside. Anything less than that runs the shape and makes the tires lose their shape.

Driving on underinflated tires creates uneven tread wear which in turn creates those cracks you see. They also help dry rot to form.

5. Chemicals- you know those tire cleansers that make the rubber look so good. Well, some of them may not be that great for your tires. There are chemicals inside that are the enemy of rubber and those chemicals can cause degradation to the surface faster.

Check the ingredients of those tire cleaners to protect your rubber from dry rot and deterioration.

Is Tire Sidewall Cracking Dangerous?


There will be RV and other vehicle owners who claim it is safe to drive with cracks on your tires. They are not giving you great advice. While they may not have had a problem YET, they may still have one if they do not replace those tires with new ones.

It is quite dangerous to drive with cracks in your tires. It does not matter the size or depth of the cracks, the fact that they are there should be of great concern to you. These cracks can deepen or widen without you knowing about it and that makes a bad situation worse.

Why are these smaller cracks dangerous? Once the cracks appear they start chipping away at the strength of your tires. Weaker tires are never safe to drive on.

As the cracks get deeper, the chances of having a tire blow out increase. Even if you have some unethical tire shop place patches over your cracks, those patches do not stop cracks from going deeper. They do not solve the problem.

Do not let any tire shop try to repair those cracks. It cannot be done and you may only have a temporary solution to an ever-growing problem.

Dry Rot Tire Sidewall Cracking Chart

Most websites are not posting a dry rot tire chart. Instead, they only post images of the different stages and identify which ones are acceptable and which cracks are not.

We will post two images, one here and one in the next section for comparison value and let you see how bad these cracks can get.


Michelin Tire Sidewall Cracking Chart

The following image is said to be a Michelin dry rot chart. We checked their website and did not find any other chart or image.


If you suspect that you have dry rot and sidewall cracking, it is best to go to a tire professional that you trust. While these images state there are acceptable levels of cracks, there really aren’t. As time goes on, those cracks will get worse as there is no way to repair them or stop them from getting bigger.

The acceptable levels should serve as a warning sign to you and get you ready to set some money aside for new tires soon. One of the signs of a dry rot tire is when you start losing your handling control as you drive.

According to some websites, there are different stages of dry rot, starting at the 6-month mark and going up by one year at a time to 5 years. We do not recommend that you drive on any tire that is showing signs of dry rot or sidewall cracks.

If you are buying used tires, then you should use these images or charts to guide your purchase. Take a look at the entire tire surface before you buy and see if dry rot or sidewall cracks have started to form. If so, move on to the next set of tires.

Can You Drive On Tires With Cracked Sidewalls?


It is best not to do it and we will not advise you to do it. This will be a decision you have to make once you get all the facts about dry rot and sidewall cracks. Keep in mind that no matter who tells you that the cracks can be fixed, they can’t.

They will only get worse. One of the reasons why this is not an advisable thing to do is because those cracks let in water and contaminants that will help degrade the rubber.

Another reason could be that air gets inside through the cracks and adds a little extra pressure. When you hit a pothole or bump that extra pressure may be too much for the tire and it will blow.

As you see by the charts above, the creators of those charts have about 3 or 4 acceptable levels before you should stop driving on those tires. But even those acceptable levels can cause you problems when you are driving.

That is because you do not know what damage is being done to the interior layers of rubber that make up the tire. After saying all of this, while you can drive on tires with cracks in the sidewall, it is not a very wise thing to do.

Should you Replace Tires That are Cracking?


Knowing that dry rot and sidewall cracks cannot be repaired, this is your only solution. Life is precious and you really should not take chances with your or your family’s lives by driving on tires with dry rot or sidewall cracks.

When you go to the tire manufacturers’ websites, you will find that they have different safety standards when it comes to cracks. Some will say driving with any crack 1/8 of an inch or larger (length and width) is unsafe.

Others will say that if the crack is 1.2 inches long and 3.8 of an inch wide, it is unsafe to drive on those tires. As we said, patches do not stop cracks from getting bigger.

They may help you get home or to a tire outlet but do not rely on those patches to keep the tire from blowing out. One more thing, with cracks and dry rot on your tires, air can escape from the inside.

This loss of tire pressure will affect not only the tire but also your handling, braking, steering, and other driving aspects. It is just not safe to drive on tires with dry rot or cracks.

How Much Cracking is Okay on Tires?


You can look at the two charts above and get a pretty good idea of how much cracking your tire can handle. The problem with those charts is that they do not and cannot show the depth of those cracks.

That is the most important aspect of these cracks. You never know how deep they are and they can ruin the materials inside very easily and without your knowledge.

Plus, those cracks do not stop growing. The more you use them the deeper and longer they will get. Even if you are leaving your RV in one spot for a long period of time, there are other elements that work that make those cracks bigger.

We are not going to say how much cracking is okay on a tire. We leave that up to the professional tire people and manufacturers. We also do not recommend taking advice from many owners at the different RV discussion forums.

Some of it is good while others are not so good. You need to make this judgment call yourself. Cracked tires are an accident waiting to happen and the trouble is, you never know what size of crack will be the one that causes the tire to blow.

Air can leak out of any size of crack if it is deep enough. Water can get in any size of the crack and start degrading the rubber. So can contaminants like harsh chemicals, so you need to be careful with those tires.

How To Prevent Dry Rot & Cracks

There are several things you can do to slow the decay of your tires. Here are a few suggestions to help you:

1. Use tire covers- this helps with just one source, UV rays, but sometimes that will be enough

2. Drive your vehicle more often- while you do not like driving RVs in the city, you still need to drive them frequently to prevent dry rot and cracks. Ask the professionals how often you should drive t your vehicle.

3. Buy premium tires- these are made with better quality rubber and are made to better standards. This helps stop dry rot from starting. Cheap tires not so much.

4. Watch the tire cleaner ingredients- try to avoid those cleaners that come with harsh chemicals as ingredients. Those harsh chemicals do harm the rubber on your tires.

5. Keep your tires at the right tire pressure- try to stay away from under-inflating your tires at all times. Check them frequently to make sure you have them at the right psi level

6. Park your RV out of direct sunlight when possible- or use underground parking lots whenever possible. Keeping your RV out of the sunlight will help more than just protect your tires.

Some Final Words

There are a lot of dangers around that can harm your tires. One of the best ways to practice defensive driving is to make sure your tires are in good shape, have the right air pressure, and have not contracted dry rot or sidewall cracks.

Once you get those cracks, it is best to replace them with new tires. The images above will help guide you in that purchase situation. It is not wise to drive with dry rot or sidewall cracks as it is a gamble if the tires will last or not.

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