Does it matter if a piece of the tire's outer surface is damaged?
2 Answers
Generally, a small piece of damage on the outer surface of a tire does not affect the vehicle's operation. However, it also depends on the depth of the damage and its location. Here are the details: 1. If the depth of the damage is less than 0.1 cm: the tire can still be used normally; 2. If the depth is between 0.1~0.2 cm: it is recommended to use it normally but avoid highways; 3. If the depth is between 0.2~0.3 cm: it is advisable to replace the tire with a spare; 4. If the depth exceeds 0.3 cm: for safety reasons, the tire should be discarded. If the damaged area is not the thinnest part, the same logic applies—the closer to the center, the thinner it is, with the sidewall being the thickest at about 1.2 cm.
I'm all too familiar with this issue of a broken tire sidewall. If the damage is on the tread (the part that contacts the ground) and it's just minor surface peeling without affecting the internal cords, it's generally safe. But if it's on the sidewall, especially near a bulge, then you're in trouble—that area is particularly thin. Once, I had a cut on my tire sidewall from a rock and thought nothing of it, only to experience a sudden blowout on the highway—it was a close call. I sincerely advise you to first measure the depth of the damage: if it's over 5mm, change the tire without hesitation; if it's shallow, still take it to a professional shop for a thorough inspection. And whatever you do, don't try to patch it with something like super glue—it's completely useless under high temperatures and can actually make things more dangerous. If you frequently drive on mountain roads or carry heavy loads, be extra cautious—don't hesitate to replace the tire if needed.
