This is an oldie but goody. I was just asked about plugging tires.
This is a very important post. Improper repair can lead to a false sense of security and even to a tire failure which can cause damage or even injury. Please read this entire post.
I recently read a statement that could be misleading as it is not supported by any of the major tire manufacturers or the National Highway Traffic Safety Administration.
The writer said that “plugging a tire can work well.” This is just as true as making a statement that you can play Russian roulette and survive or you can beat the odds in Vegas or you can survive jumping out of a plane without a parachute.
Guidelines for proper repair of a tire for highway use are available from a number of sources.
Your well-being may depend on following these guidelines from NHTSA.
“The proper repair of a punctured tire requires a plug for the hole and a patch for the area inside the tire that surrounds the puncture hole. Punctures through the tread can be repaired if they are not too large, but punctures to the sidewall should not be repaired. Tires must be removed from the rim to be properly inspected before being plugged and patched.”
If you don’t trust NHTSA, How about Goodyear?
“It is crucial to know when it is okay to have a tire repaired and when a tire should be replaced. If a tire loses its air pressure, it must be removed from the wheel for a complete internal inspection to be sure it is not damaged. Tires that are run even a short distance while flat are often damaged beyond repair.
Most punctures, nail holes, or cuts up to 1/4 inch can be repaired by trained technicians as long as the damage is confined to the tread. DO NOT repair any sidewall puncture. Most tire repairs should be handled by trained professionals.”
If you don’t like Goodyear, maybe Michelin?
“There is a good chance that your tire can be repaired if:
1. The tire has not been driven on when flat
2. The damage is only on the tread section of your tire
3. The puncture is less than ¼"
However, you need to have an authorized tire retailer or technician remove the tire from the wheel and inspect the tire from the inside. This inspection is absolutely necessary because internal damage is not visible while the tire is mounted.
The proper way to have a tire repaired is to patch the tire from the inside and fill the puncture hole. If someone offers you a plug repair, refuse! Plug repairs do not involve taking the tire off the wheel for a proper inspection. A plug is simply inserted into the punctured area. Plug repairs are not reliable and can lead to tire failure. Insist on a full inspection and patch and fill repair on the inside of the tire.“
OK, not Michelin, then maybe Bridgestone Firestone?
“Tread punctures or penetrations left unrepaired may cause irreversible tire damage. An improper repair can damage the tire and will void the warranty.
Combination patch/stem repair. Steel cord damage must be repaired immediately to prevent rusting of the steel. Using plugs or patches alone on any type of tire is not a safe repair.“
Here is an example of a tire with three plugs and the owner also used a sealant that goes through the valve, all in an effort to save a couple of bucks.
Here you can see the cracks through the interior rubber of the tire from driving hundreds of miles on an under-inflated tire.
This tire had a piece of wire sticking into the air chamber. You can see where it was wearing through the interior.
None of these “repaired” tires were dismounted as instructed by tire manufacturers but each had a cheap, improper plug repair made by someone that thought they knew something about tires. I will leave it up to you to judge the quality of the suggestion that a plug is acceptable repair and "can work well".
As you can tell this topic is a “Hot Button” for me as I have seen entirely too many improper repairs done by the uninformed in the name of saving a couple of bucks.