My '05 8 came only with the sealant tire repair kit as well as a jack for a spare should I opt for one. Since most tire problems I have had over the years have been nail/screw punctures in the tread area, I thought the enclosed sealant kit was a pretty good idea; however, the owner's manual says that a tire repaired with the sealant cannot be reused and Mazda recommends replacing the tire. That sounds like an expensive fix. Granted, it would get you out of a situation and back home with less hassle, but for almost the same effort wouldn't it be more practical to repair the tire from the outside with a plug? Over the years, once my tires have been plugged, I have been able to drive them until the tread indicated replacement was needed. Am I missing something here? Are plugs not recommended in this type tire? I realize that damage to the sidewall or a blowout would make me wish I had an actual spare, but doesn't the plug idea make more sense than the sealant approach?

 

You can plug it from the inside or apply a patch (from the inside), but keep in mind that with any of those repairs your speed rating for the tire goes out the window. I don't think any reputable shop will plug a radial tire from the outside. Repairs can only be applied to the tread area, anything on or near the sidewall - need a new tire.

 

They apply patches to the interoir of the tire. The sealant cans dissolve the rubber so it is sticky and bonds to itself (shares electrons), sealing the hole. It destroys the enterior of the tire and they never balance right again. If you get a nail then put on the spare, have the tire patched and you'll be fine unless you dirve 100mph.

 

Are you sure that plugs are not to be used? I could be wrong, but I'm guessing I have had radial tires for a number of years and that the nail holes were plugged from the outside.

 

Permanent repairs are done from the inside with a patch that has a plug extension. The extension has steel bead inside so it doesn't get cut by the tire's belts. The plugs you can buy for insertion from the outside will get you going but should be replaced with permanent patches applied from the inside.