Sidewall Bubble in Tires – What Are They and What Should You Do?

If finding a bubble in your tire’s sidewall has led you to this blog article, then there’s a good chance you are looking for answers to several questions:

  1. What causes a sidewall bubble?
  2. What is the impact of a sidewall bubble?
  3. Should the tire be repaired, or replaced?

We hope that the following information will help.

What causes sidewall bubbles in tires?

Tire Bubble

cc: Warenski

The underlying cause of a tire bubble formation is the separation of layers of material – plies and rubber – in the sidewall of a tire. You may already know that a tire is constructed by layering hundreds of polyester cords or other strong materials (also known as plies) with layers of rubber, sometime cemented together by bonding materials like glue. The rubber layers hold the air in the tire while the plies provide structure, shape, and strength to the tire under pressure. Since the durability of a tire is dependent upon the bonding strength between these component layers, a loss of bonding strength can lead to ply or layer separation. Loss of bonding strength and separation can be caused by several factors, among which are:

  • Contamination of components or other defects during manufacturing (a rare occurrence)
  • Under inflation or over loading of the tire (more common – depends on the driver)
  • Tire damage caused by road hazards such as striking the curb or hitting a pothole (most common – often the driver is unaware of the incident)

When a layer separates due to one of these factors, air can permeate through one or more internal layers, migrate toward the outside of the tire, and collect under the outer plies (layers) of the tire.  As a result, the outer rubber layer in the area of the internal damage may bulge or bubble.  This is always a sign that pressurized air from the inside of the tire is migrating through the internal tire structure and is trying to escape.

What is the impact of a tire sidewall bubble?

Since it is always a sign of internal failure, continued use of the bubbled tire can lead to continued gradual weakening of the over-strained cords which can cause a larger bulge and eventually cause the tire to fail, perhaps catastrophically.  A weakened tire is much less able to handle road hazards like potholes.

What should you do if you have a sidewall bubble?                                                                                   

Any tire that develops a bubble (in the sidewall or the tread) is not repairable.  The internal structure has failed and the tire itself is very likely to fail at some point. The tire bubble may grow or get larger over time as the air pressure continues to delaminate the inner plies.  Or, the tire can suddenly fail catastrophically. While the pressure may hold for some time without the tire failing, continued driving, driving at high-speed, or more impacts to the tire like speed bumps or potholes will continue to worsen the problem leading to eventual failure.  Bottom line, continuing to use the tire is a risk you should avoid.

If your tire has developed a bulge, you should have it inspected and replaced as soon as possible by a reputable tire dealer.  You should not continue to drive the vehicle as your safety is at risk.  Many people think a tire bubble is usually caused by a manufacturing defect.  If your tire experiences a sidewall bubble from a defect, all reputable tire manufacturer’s warranties will cover replacement.  However, it is extremely unlikely that a defect caused a bubble and 98%+ of the time, a reputable dealer will be able to point out to you evidence of damage to the tire caused by a road hazard.  Road hazards are rarely covered under standard manufacturer warranty policies.

However, road hazard insurance bought when you buy new tires will cover all, or some, of the cost of replacing a tire that has a sidewall bubble caused by road hazard damage; check the paperwork that came with your policy for the specifics of your coverage.  When buying road hazard insurance, make sure you understand any limitations of the policy that might restrict coverage.


At AutoSquad, we always appreciate your feedback and try our best to respond promptly to any questions. So, please free to share your thoughts on this article, or ask us questions you may have on this or other topics.

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8 thoughts on “Sidewall Bubble in Tires – What Are They and What Should You Do?

  1. Tony

    so what is the best tire to withstand a city where potholes are everywhere (aka nyc, aka brooklyn)? I currently have nexxen 7000′s size 245-45-r17. Im so tired of just shelling out money every 5-6 months for a new tire here and there. thanks for any help

    1. tsodhi Post author


      Thanks for the question. Unfortunately, there are no particular tires that are known as “pothole safe”. The best way to ensure protection against potholes is to drive at normal/average speeds since a high speed impact with a pothole can cause a tire blowout. Another way to protect yourself against such road hazards is to purchase Road Hazard Warranty. Most retailers offer 3-4 year protection plans at a small additional fee which cover your tires against damage caused by road hazards like potholes, nail etc. Also, in some cases, you can file a claim with your local jurisdiction to be reimbursed for damage done to your vehicle due to a poorly maintained road so we would advise you to look into that option as well.

      As for the Nexen 7000, how do you feel about the performance that those tires have provided you so far? If you are not happy with some aspect of that tire’s performance, definitely share that with us so we can try and suggest some better options for you.

  2. Mr Smith/ Smyrna Video

    Nexen tires are cheap and cheap! Buyer Beware! I would not purchase a Nexen tire if I had too!!
    All four of my Nexen tires developed a bubble on the side wall? The dealer said it was my fault??
    I was an 18 year old customer of the tire shop!! Good-bye Tire World Smyrna,TN 37167

    1. tsodhi Post author

      Chances are unlikely that the fluid from the shocks have caused a tire bubble. Generally, a bubble is caused due to damage to the steel belts inside the tire. This normally happens if there is a direct impact to the tire at high speeds so hitting a curb or a pothole, etc. There are other reasons that the tire belts could break as well but fluid from shocks is probably not one of them.

  3. Dr Rahul Bagrecha

    how a company decides cause of sidewall bubble to a tyre.Its obivious they will always point a finger to us or road condition for denying a claim.

    1. tsodhi Post author

      Dr. Bagrecha,

      Generally in cases of sidewall bubbles you can see some visual indication of a tire hitting a curb or some sort of a road hazard which leads to breaking of one or more of the steel belts in the tire and thus causing a bubble. We recommend that you protect yourself against these road hazards by purchasing a road hazard insurance policy that is available through most tire retailers at a minimal cost.

  4. obiorax

    I appreciate this article. Both timely and informative. I quite agree that entering a porthole at speed in excess of 80kmph can cause side bulge as I experienced recently. I suffered side bulge on both front and rear tyres on passenger side from single occurence.
    Thanks for the candid advise of replacing tyre, though at an unplanned cost.


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