Some damaged or flat tires can be repaired, but in other cases, it is better to replace the tire. Whether or not a tire can be repaired depends on the extent of the damage and how early the driver notices the problem.
While a simple tire puncture can often be patched, a tire that has been driven on while flat or low on air may incur additional damage that makes it necessary to replace it. One sign that a tire is too damaged to be repaired is scuffing and wear on the tire sidewalls. Even minor scuffing on the outside of the tire is cause for concern because damage may be much worse on the inside of the tire.