We were out enjoying the sunshine yesterday afternoon when the tire pressure monitoring system started reporting a pressure drop in the right front tire. I should hasten to mention that we were in the spouse's Camaro, NOT my 'Stang. We could not get back to town to a gas station before the pressure dropped to 0 psi, leaving us on the side of the road. There was a 1/4" hole in the tread, which the tire mobility kit was NOT able to handle. The goo ran out the hole as fast as it was being pumped in. So the Camaro got towed home in shame.

We proceeded to plug the tire. The first jacking point the spouse chose was wrong; car was 6" up when the jacking point snapped and dropped the car. Moved the jack and finally got the car up on jack stands to find that the tire plug reamer went easily into the hole up to its shoulders. We plugged the hole with a self-vulcanizing plug, but the plug went in so far that only one "tail" stuck out of the hole. The tire seemed to hold pressure afterwards (haven't checked it this morning).

Has the plugged tire lost its Z rating? Or is it good as new assuming it holds pressure? I'm inclined to replace the tire before doing any spirited driving. The spouse wants to use the tire, which has <4K miles on it.

Also, an observation that the spouse's preparedness in having a tire plug kit in the trunk was totally offset by the lack of a jack in the trunk to get sufficient access to the tire to plug it.

Thanks in advance for your stories, advice, tips, etc.

 

I use the standard kind of plug kit. A round file and a tool to insert the plug. If the file goes into the hole in the tire with little resistance, the hole is too big to plug .

 

A plug is a temporary fix. The movement of the tread surface will eventually cause the plug to fail. However, that doesn't mean the tire must be replaced... you can take it to a tire shop and have them apply a proper internal patch to repair the hole. It will cost you for dismounting, patching, remounting and balancing but it's a lot less than the cost of a new tire.

 

No way no how, I've seen what happens to tire and car after a plug gives way at highway speeds. I know it sucks big time to replace a fairly new tire, but it's worth it.

 

I had a simliar tire problem on my wifes Taraus. I called Ford they sent me to the tire mfr. Goodyear. They couldn't repair the tire because it was a side wall puncture. They did prorate the tread wear (only had 4k miles) and I got a new tire. Make a long story short I called Ford back and between Ford and Goodyear the new tire cost me $80. I also asked Goodyear could I buy tire warranties for all the tires and they said yes for $15 a tire I got an all road hazard warrenty just like new tires including free rotation and balancing every 5k.

 

As Whitebird00 stated, a plug is a temporary fix, to be properly repaired the plug must be covered with a patch (and a patch by itself is an incomplete reapir as it must be accompanied by a plug in order to fill the hole completely).

Properly done, and that's key making sure a flat repair stands the test of time, even under severe operating conditions, it shouldn't fail for what most people do with a car (motorsports being another realm altogether).

If your refering to catastrophic failure of a tire at highway speeds, the plug itself wasn't the problem - it was an improper repair that either allowed the plug to eject itself or the plug was leaking. In either event, the tire suffered a loss of air and built up a significant amount of heat (if your indicating the tire came apart or blew up) leading to its disintegration.

Agent, I know on some brands, a 1/4" hole is at the upper limit of what can be repaired with a plug and a patch. This is per RMA guidelines and the tire manufacturer may have guidelines specific to thier product. Also a single flat repair may or may not alter the speed rating of the tire.

 

plug an old tire patch a new one! Never heard of patching over a plug before. I would say thats a no no. If the hole is to big for a patch replace the tire. Not worth taking a chance with a 35k car.

 

Where I live, I pick up probably 3-6 nails across all tires over the life of them (approx. 2 years or so). I've always patched them and would not trust a plug. It would also be insanely expensive to replace a tire every time I picked up a nail.

 

With the miles you have on this tire, take it in and get it replaced. You have no idea what can happen if you lose that tire at high speed. I had a tire, on a government vehicle, blow on the Interstate just as I was passing a semi. Fortunately, I maintained control, after almost swerving under the center of the trailer when the tire blew pulling the car violently to the right.

For you wife's safety, please replace it.

 

I would trust that tire to get me straight to the nearest tire shop for a new one, and absolutely no further.

 

... actually, I am the wife.

Thanks to all who have responded so far. I've shared your advice, but he just got home from taking the tire to the tire dealer, who patched it. He said they did not answer his question, whether patching the tire voided its Z rating. I think I'll get him a tire for his birthday in addition to the exhaust I was planning on.

 

"... actually, I am the wife."

I apologize...I should have picked up on that when you used the word "spouse" and Camaro in your OP.

 

According to Goodyear in a service bulletin to police departments about repairing speed rated tires, a properly plugged and patched tire will retain its speed rating and warranty. They have all kinds of specifications regarding what constitutes a proper repair (materials used, size of hole, etc.). You can read more here.

Besides, unless you plan to drive up to 149 MPH, the Z rating is unnecessary. Many people seem to think that a higher speed rating indicates a "better" tire but anything higher than H (118 MPH) is completely unnecessary for the average driver. That patched tire is just as safe as before the patch and there is no reason to replace it (assuming the tire shop repaired it properly).

 

No its fine, old or new a patch must be used in conjunction with a plug to properly repair a tire. If somebody is uncomfortable patching over an exsisting plug, its easily removed and a new plug can be inserted in its place.

A patch by itself does a good job of sealing the inside of the tire but does nothing to protect the belt package from the elements which could lead to failure.

This is one source for broken belts in a tire - punctures that only penetrate the tread and do not go any deeper than the belts in the tire allowing the belt package to rot and weaken.

A plug by iteslf can effectively seal a tire (and in many cases stop a leak) but at some point the plug can start leaking again since it is only minimally in contact with the tire (especially the inner liner) where a patch provides a much greater sealing surface.

The RMA (Rubber Manufacturer's Association) sets the guidelines for flat repairs and accepted practice is to repair a hole no larger than a quarter inch. Using the method I described - a patch in conjunction with a plug.

I know in the case of one tire manufacturer that sort of repair is suffcient to maintain the speed rating of a tire with just one puncture, after than though the tires loses its speed rating and has to be considered a standard passenger tire (no faster than 112 mph).

Like I said, properly done a patch can do pretty good, I can attest to that on numerous instances of what would be considered aggressive drivng.

Of course thats key to the whole process as a proper flat repair involves several steps;

A) The tire needs to be inspected for damage - not just the puncture site, but the sidewall and the interior.

B) If the tire is repairable then the tech needs to prep the hole and surface of the inner liner. The former by reaming out the hole until its round (jagged holes just like sharp corners can create cracks the spread) and filling the hole with a rubber plug, the latter by begining sufrace prep by cleaning off any manufacturing and/or mounting chemicals that are present on the inner liner (typically with a pre-buffing solution in conjunction with a scrapper).

C) Once the inner liner is clean then the actual buffing can begin, the object here is not to grind down into the inner liner (which is really really thin - being synthetic rubber which holds air better but rejects heat poorly in comparison to natual rubber) but just scuff things and increase the surface area that the cement and patch can adhere to.

D) The tech then applies the cement and allows it to air dry (typically 5 minutes) - using heat of any kind can affect the performance of the repair - holding a lamp over the cement to accelerate drying can cause the cement to skin over and prevent proper drying. Actually setting it on fire to accelerate drying ruins not only the cement but also the tire (in general only low speed air and electric tools should be used. Anytime you smell or see burnt rubber, the tire is ruined for the purposes of the reapir).

E) The patch is applied and stitched down with a roller - Its best to use a large diameter patch (2 or more inches in diameter) since the actual amount of adhesion can be pretty low.

F) A final step that can be applied is to use something called inner liner sealer - the inner liner sealer as the name implies addresses any possible problems with the buffed area being compromised.

G) Replace the valve stem or in the case of a wheel mounted sensor, replace the gaskets, retaining nut and schrader valve.

H) Inflate to 40 psi and inspect again to see if the patch/plug was successful.

I) Balance the tire then adjust to the specified air pressure and place it back on the vehicle.