Possible nail puncture in tire - what to do

5000 miles on 2021 subaru forester. A month ago drove over a piece of a broken dollhouse with 10/32 inch long nails sticking straight up from the wood (about 2mm diameter - perhaps similar to a thumbtack). 8/32 inch tread left, based on the car tracks it may have gone into the tire shoulder or perhaps a bit more towards the center of both passenger side tires. No air leak.
I asked my mechanic to inspect the tires for obvious holes, but he seemed unimpressed and I am worried the holes (if present) might be hard to find, so not sure whether to trust his inspection as adequate.

If this punctured the tire without causing an air leak, might it have gotten into the belts and caused dangerous structural damage (or risk structural damage over time, with water entry/etc)? If so, would this become noticeable while driving before a catastrophic event were to occur?

Trying to decide how aggressively to search for holes in the tire without an air leak vs ignore it vs buy 2 new tires.


Your mechanic is probably not a tire person but if you are not losing air then you have nothing to worry about . Just check the tires ( all of them once a week for a while ) . Then return to checking them once a month .


A nail that size that’s been removed and doesn’t cause a leak does not concern me.

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Agree with the previous 2 posts… drive on, no worries.


I understand your concern. I had my extended tape measure laying on the garage floor and backed over it. The sharp end got imbedded in my front tire. No air leak but when I measured the hook and the remaining tread (I don’t remember but had maybe 30K on the tires) the hook went beyond the tread in the tire. With the tires down to yellow on tread gauge, and winter approaching, I just put new tires on. The risk was probably slight but the idea of changing a tire at 10 below on the freeway, with tires about 75% worn, and wanting tires with good tread for snow, made the decision reasonable.

Tires with only 5000 on them and a tack like puncture I guess wouldn’t be so concerning to me. Depending on how far in the nail went. Usually you still can’t replace just one tire though, although 5000 miles may be ok. But with FWD or AWD its either two or four.

I doubt that a 10/32" long nail even got as far as the belts. BUT, an air leak can be so slow that it takes a month or two for the tire to be noticeably low. You could just check the pressure each week for a month or two. Personally I’d just look at the tire to see if it looks lower than the others rather than check with a gauge. Only use the gauge if the tire looks low.

There will be a small loss of air every time you check the pressure, that can’t be helped but if you don’t loose 10 lbs or more in two months, then I would not worry about it. Most of that will be from checking. After 2 months, air up the tire and drive on.

Check the air in all the tires weekly and see if there is a difference in pressure between the ones that you nailed and the other ones. If there is a slow leak and there are no nails still in the tire, you could take it to a shop and have the tire tested for leaks. When they find them, they can patch them on the inside. Next to replacing the tire, that’s the premier fix. Another method is to use a liquid tire sealant. That’s faster, cheaper, and maybe not as safe.

You can take a soapy solution and spray it on the tire and let it sit. see if you see any tiny bubbles form. if not, I would not worry about it.


I’m certain there is no air leak. I just wasn’t sure what risk a 2-3mm diameter hole that goes 10/32 inches might cause to the structure of a tire if it doesn’t result in a leak.

Drive on as others have said. Got a spare? Roadside assistance? Keep an eye on the pressure, all good is all good in my book.

Think of it this way-had it gone all the way in and caused a leak, you would get it patched and drive on with no problem. The nail would have caused the same damage to any cords.