Posted on 8/28/2026
A bubble on the sidewall of a tire is hard to miss once you see it. The tire may still hold air, the car may drive normally, and there might not be any warning light on the dashboard. That can make the damage seem less serious than it really is. What you are seeing is not extra air trapped under the rubber. A sidewall bulge means the tire's internal structure has been damaged enough for air pressure to push outward where the tire is no longer properly supported. A Hard Impact Is the Most Common Reason Potholes, curbs, and sharp road edges can hit a tire hard enough to damage the cords inside the sidewall. The outside rubber may survive the impact without splitting, but the internal reinforcement can break. We often see this after a driver remembers hitting a pothole but does not notice anything wrong until later. Sometimes the bubble appears almost immediately. Other times, the weakened area becomes more obvious after several drives as normal tire pressure cont ... read more