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Tire Plug

Brand new tire got a nail in it. The guy at the tire shop put a plug in it and said it will bond with and last as long as the tire.



Is that true?

I have never seen a properly installed plug in a nail hole fail…Key term is “properly installed”.

The BEST repair method involves inserting a plug/patch from the INSIDE of the tire. That seals the air liner inside the tire AND it seals the steel belts from moisture penetration which can, over time, lead to belt failure.

The problem with some plugs, the installer fails to follow the original puncture and instead makes a NEW hole with his probe. He then repairs this new hole, which appears to work as the hole is sealed at the tread surface. But inside the tire, the unrepaired hole allows air to push into the ply layers, which can lead to ply separation…

If you are going to pay for a tire repair on a new tire, I would INSIST the patch was applied from the inside to guard against future problems…

There might be some new technology that makes plugs better today than they used to be. My preference is to put a patch on the inside of the tire. This is more expensive than a plug but that’s ok by me.

If the plug job was pretty cheap, then you might not mind paying for a repair via the patch method. Since it is a new tire, it is worth the money to get the best fix you can.

I have never had a problem with a properly installed plug. In fact, in times of need, I have installed my own plugs in my tires. Admittedly, I had no idea what I was doing. I just bought a kit at an auto parts store and did my best to follow the directions. They also worked just fine without problems.

Sometimes I think this whole “patch from the inside” is a way to increase profits. Maybe installing plugs didn’t generate enough profit. Maybe as tires improved, and more people started driving on “high performance” tires, they wanted a more thorough system.

When lawyers get into the picture, all bets are off…Today, it’s difficult to get anyone to repair a tire at all…ALL punctures are becoming “non-repairable”…

“Our insurance regulations no longer permit us to repair tires…”

I would like to know if a lawyer really said that, or if the tire retailers are blaming the lawyers so they can sell more tires. If you use that line on someone with AWD, you might be able to sell a set of four tires, not just one. That’s a lot more profit than installing a patch on a single tire.

I’ve seen many plugs fail, and I have seen tires fail as a result of plugs.

I’ve also seen tires fail as a result of plug / patch combination repairs, just less than plug type repairs.

So there is some truth to this. Repairing anything involves a risk.

My experience is that plugs are generally OK. I’ve had a few start leaking air slowly after a year or two requiring extracting the old plug and putting a new one in. Not complicated or expensive.

If your car doesn’t do automatic tire pressure monitoring, you might consider investing $20 or so in pressure indicating valve caps that will let you know if the plug starts to leak by turning yellow or red. That’s not a bad idea anyway because tires occasionally pick up nails or similar stuff that causes slow leaks. But you need to check the caps every week or two for them to do any good.

There are several kinds available I think. Here’s a link – http://www.autogeek.net/kwtc.html

I had to plug a tire myself just the other day. It was a simple nail hole in the center of the tread. All the tire shops I went to refused to do it, they all said there wasn’t enough tread (3/32 inch) and only offered to sell me new tires. Admittedly, I’m going to need new tires soon anyway but c’mon.

I bought a Gorilla Grip patch kit from my neighborhood auto parts store and followed directions. Plugging the tire was easy and it now holds air. I figure I’m good to go.

If you really only have 3/32 of an inch left, they were right to refuse to fix this tire. You need new tires now. The limit should be at least 4/32 of an inch.

Since probably 90% of flat repairs are done under warranty these days, how would that increase profits?

I think most places have just realized that really there’s not that much time to be saved doing a plug properly versus just doing a patch.

Yes, it is usually true. A patch fails more often if it is done wrong while a plug is meant to be done wrong.

For those who pay for a tire repair, a plug costs less than $10, while a patch can cost up to $45. Also, if it is warranty work at a franchise, the tire company still has to pay the franchise shop for the work. Even if it is a company-owned shop, the tire company still has to pay the employee to patch the tire.

Seriously? $45? The most I have ever been charged for a flat repair was $15, and I was pretty peeved by it. At least in my experience, $7-12 is more typical. My regular tire place does them all for free because they figure it’s good public relations and they’re not worth the trouble of billing.

At the last car fixin’ job I had, we got .2 hours for doing a unmount and patch flat repair. Barring annoyances with getting the spare back in the car, etc, that usually was about as long as it took. I’ve never actually done a plug, but I seriously doubt there’s that much time to really be saved. You usually have to take the wheel off to find the leak anyways, and an experienced tire technician can mount or unmount a tire in less than a minute, so I think most shops just figure it’s better to take the extra two minutes or whatever to do a patch. I suspect the materials are probably cheaper too.

I, like Whitey, had numerous plugs installed over the years, none with an inside patch. I have never, ever had a plug fail.

I’ve read all the dissertations, read all the so-called “tire experts”, and still truely believe that an inside patch s overkill.

Yes, I have seen tire chains charge that much for a patch and plug. For $15, I would only expect a plug without the interior patch, especially since the wheel will have to be rebalanced after the new patch is installed. This was in a new used vehicle for which the tires were not covered by any warranty. If they had been tires that I had purchased directly from the tire seller, the cost would have been much lower. You are right, plugs don’t take long, but patches require the tire to be removed and rebalanced, after the glue on the patch has had a chance to cure. According to the service adviser at Pep Boys (whose integrity is always in doubt), the patch takes longer than 0.2 hours.

I tried those pressure indicating valve caps, and they have proven unreliable for me. There is no substitute for a tire gauge, and having those valve caps can give one a sense of false security. I believe drivers are better off without them since having them may lead to checking with a gauge less often.

…a plug is meant to be done wrong.

What does that mean?

To the best of my knowledge, the major tire companies consider the combination patch/plug to be the only acceptable method of repair.

The reason is that an interior patch by itself will allow water to migrate through the exterior hole into the steel belt, and this–obviously–can lead to rusting of the steel belt. And, a plug by itself can cease to hold, given the flexing of the tire tread, especially if the car owner allows the tire to run with low inflation pressure in it after the patch repair.

By contrast, the combination patch/plug will help to stop the migration of water into the belts, as well as resist the tendency for the plug to pull out, because it is firmly anchored by the internal patch.

Recently, a friend had a puncture in a fairly new Yokohama tire. I insisted that we take it to the Goodyear shop in my town, simply because I know from experience that they use the combination patch/plug. The cost–$37.00, including tax, was outrageous in my opinion, but at least the tire was repaired properly.

That fee also included dynamic balancing of the tire because it had to be taken off of the rim for repair. While this repair cost more than I paid for a new tire years ago, at least this should allow my friend to get the remaining 10k or so out of the tire. (Since these are “original equipment” Yokohama tires, the wear rating is ridiculously low–something on the order of 160!)

The wheel doesn’t have to be rebalanced, you just mark where the weights and valve stem go and put the tire back on at the same orientation when you took it off.