Obviously, a clear sign of damaged tires is loss of air pressure.
Suppose you discover that one of your tires is losing air. The first thing you need to do is find yourself a safe place to remove the wheel. This is when all of those times you checked that your spare was in good shape finally pays off.
The vehicle manufacturer will have supplied instructions using the jack, removing a wheel and installing the spare. If you haven't done this before on this vehicle, take time to read those instructions before you start -- things may have changed from the last time you did this and not all vehicles work the same way.
After the damaged tire is removed and the spare in service, take your damaged wheel to a suitably qualified dealer. They will remove the tire from the rim and look for reasons it was losing air. Do not be tempted to try to drive your car with a deflated tire, not only can you completely ruin the tire, but you could lose control of your vehicle.
Repairs are possible to tires if the damage is caused by a reasonably small object and isolated to the tread portion of the tire. Punctures up to 1/4 inch are generally repairable. Tires must be repaired using industry-approved methods, preferably an inside repair unit, also called a patch and plug.
A patch and plug repair must seal the inner liner (patch), as well as fill the injury (plug), to be in line with the Rubber Manufacturers Association requirements for permanent tire repair. Using tubes to repair tubeless tires is definitely unacceptable and dangerous.
A specific tire manufacturer's specifications should be consulted on whether the factory speed category still applies to tires that have been repaired. Consultation with manufacturers should also occur if tire damage is larger than a quarter-inch to the tread area.
The risk is simple -- tire failure. The consequences could be fatal, so be extremely cautious about even considering repairs to damage exceeding a quarter-inch.
Patch and Plug repairs can never be used to repair damage to a tire wall.
What about those aerosol cans that fill the tire with foam?
Aerosol sealants and inflators do not fix a damaged tire. They provide short-term repair to help get you off the road and to the nearest tire repair facility. I’ve seen situation where changing a tire on-site is simply so dangerous that all cars have to be towed away just to change a flat. Many accidents have occurred where people are hit by another vehicle while they are changing their tire on the side of the road, so be very careful.
Tires can be saved if they are removed for proper repair but your safety is more important than saving a tire. If you have to risk ruining a tire to get safely off the road then do it.
You can never be too cautious. If there is an impact to one of your tires, such as hitting a pothole, have it removed and inspected for damage. A tire look OK on the outside after receiving some blow, but it could fail later.
There are many ways to help keep your tires in tiptop condition and get the most out of your investment. Read Dangers Associated with Damaged Tires Part III, for pointers on how to maintain your tires and avoid costly damage.
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