Why Can’t You Patch a Tire Shoulder – You Need To Know This!

Why can’t you patch a tire shoulder? Many people have asked this question as they are in this situation and have to spend a lot of money on a new tire.

Patching is a repair method used when a tire becomes flat.

The above tire damages are caused by being poked by a sharp thing or because the wall is not strong enough to withstand the friction from the road surface, causing the tire to erode.

In such circumstances, many drivers prefer to fix rather than replace as it would help save a lot of money while maintaining quality.

However, it is almost impossible to tire shoulder repair. Here is the reason.

What Is Patching?

why can't you patch a tire shoulder

There are two common ways to repair your tire when you run over a sharp object, plugging and patching. We need to differentiate them to understand tire patching clearly.

Tire patching is using a small patch of rubber with a sticky back which is put inside the tire.

Meanwhile, A tire plug is a piece of leather wrapped in rubber that is put into the hole and normally seals on the tire interior.

Generally, tire patching is tougher than plugging, although it needs more effort and time. People normally prefer tire patching to its counterpart.

What Is A Tire Shoulder?

The shoulder of a tire refers to the outside tread edge, which goes around the tire sidewall.

For easy imagination, a tire will consist of a steel belt, inner liner, tire bead, sipes, tread, grooves, sidewall, body plies, and shoulder. The shoulder is the region in which the tread and sidewall connect.

So you can see this area is unflavored for sticking to anything.

Why Can’t You Patch A Tire Shoulder?

Tire repairs are typically restricted to the tread area’s center. A tire with a sidewall or tire shoulder puncture cannot be repaired.

The graphic below shows the only tire repairable portion of your tire. The shoulder is not included.

As you run the automobile, the shoulder and sidewalls are designed to flex. Their structure is not as strong as the face of the tread.

So, if these sections are damaged, you must destroy the tire and replace it with a new one.

A puncture repair unit in the shoulder will be exposed to extra stress due to the high flex characteristics and higher heat accumulation. This might result in a tire failure soon.

The worst case has an incorrect patch as well. The air will most likely keep leaking or result in a bulge or blowout on the tire. It is potentially risky for the driver.

How Do You Repair Tire Punctures Properly?

Water can penetrate the tire body and begin corroding the belts when there is no solid seal. For that reason, tire sealant sprays for emergencies are not advised as long-time treatments.

A good patching/plugging repair closes the puncture from the tire interior and through the damaged channel.

A few more steps are required following industry standards. They devised an acronym to aid in remembering the steps: R.E.P.A.I.R.

Remove: The tire must be separated from the wheel assembly for a thorough inspection.

Examine: After removing the tire, the puncture could be carefully examined to identify the angle and size of the damage.

Prepare: Once the tire has been confirmed to be in a sufficient state to repair, the repairman prepares the rubber surfaces for optimal adhesion.

They first drill out the damage with a carbide cutter to remove broken belts or cords. The inside liner is next cleaned to a rough finish.

Apply: We apply vulcanizing fluid via the damage and wait for the air to dry it for 5-10 minutes.

Install: The two- or one-piece repair is inserted in the injury channel, and the patch component is properly attached to the inner liner with a tire stitcher to remove any trapped air beneath the repair.

Return: The tire is now ready to be reinstalled on the rim.

When Can A Tire Not Be Patched?

When Can A Tire Not Be Patched

Besides the unrepairable part, the shoulder, in many cases, the tire is impossible to fix. Let’s find out what the scenarios are below.

The Hole Is Too Big

You can never fix a hole larger than 6mm. The more the injury length, the greater the expansion issues.

Furthermore, when the ripping of the air exit is extended, the body structure increasingly breaks down.

The wear indication that reaches the 2/32 inch is another thing you should pay attention to. Danger can occur at any moment since traction is not enough when driving.

Your Puncture Is In The No Repair Zone.

The sidewall of a tire is impossible to repair in some parts because it is rather flexible. Many things, such as gravel, strike the wheel as it moves.

As a result, the interior body is more substantial regarding the structure. When damage occurs in the sidewalls, the tire patches may peel off when driving, causing air to escape.

It Got Stuck By a Meteorite

Many car owners have faced this problem. It is normal weathered rocks, but the portions around the crash can melt due to the meteorite’s temperature.

You Have Run Flat Tires

The air can be released slowly in the beginning, thanks to the pressure. Thus, people can have more time to drive to a repair shop.

However, this is not advisable because the body pressure has unintentionally worn the surface while moving, worsening the issue.

Your Tire Has Other Issues

Aside from the indicators mentioned above, there are several more reasons people cannot fix the tire.

Namely, the rips are severe, and the wear cannot be concealed. The wear index has got to an unacceptable level.

Besides, you will be unable to fix it when you do not have the information with the old one. Metal fragments can be found all over the sidewall.

How Close To The Edge Can You Plug A Tire?

In certain areas, rules prevent the repair of any shoulder and sidewall damage caused by tire punctures, no matter how small.

You can, though, repair a puncture on the tread far from the edge. The safe distances are different depending on the tire you are using.

For a tractor tire, it is likely to patch a puncture that is 1 inch or farther from the shoulder. Meanwhile, people can repair a puncture situated 1/4 inch from the edge of a car tire.

Thus, when you see a puncture close to the edge, you should bring it to a technician for a thorough inspection.

The shoulder of tire is the place where the tread glides to the sidewall. It and the sidewall are unsteady areas, so you should avoid trying repairs by yourself, which is potentially risky to your life.

Frequently Asked Questions

Is It Safe To Patch A Car Sidewall Tire? 

In contrast to the tread region, the sidewall lacks a corded belt which gives some support if injured.

That is to say, if your sidewall is pierced, its integrity is permanently affected.

For this reason, legislation enacted by organizations such as the United States Department of Transportation (D.O.T.) declares that puncture on a sidewall is not fixable.

It is not advised to patch the sidewall on self-sealing tires since their features are intentionally to aid in the case of a puncture to the tread.

What Are the Dangers Of Driving On Plugged Tires?

The first question is whether you should patch the puncture.

Fixing a puncture on the sidewall or nail in the tire shoulder is not recommended. Just think about getting it to a tire expert.

Another point to consider is the puncture angle. The people in tire repair shops will find it difficult to fix. Also, replacing worn tires is preferable to attempting to fix them.

These situations will all put your life at risk, so depending on how bad the tire is; you can consider using a new one.

Are Tire Plugs Permanent?

No. Tire plugs are only a temporary solution until the tire is professionally repaired by a tire engineer. Tire patches are a better choice, but it needs more time and work.


Now you have the answer for why can’t you patch a tire shoulder. If you face this situation, consider changing it to a new one.

Otherwise, you should take it to a tire shop for a thorough tire inspection. They will let you know if your case is repairable or not.

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