You might be in luck, total thickness of a tire is usually 13-15 ish mm

 

Kwik-Fit should have told you if this was an immediate safety concern, so probably it isn't such.

If the screw's not gone right through and hasn't damaged the cords providing the tyre structure, it should be just fine. Check the pressure and inspect for any bulge every few days for a while. (I'd mark the location with a bit of chalk on the sidewall, if I could find a stick of chalk, to make this easier.)

 

This sort of situation is difficult, because there’s always a possibility that the screw has penetrated just enough to cut/weaken some of the fabric weave that runs around an upper layer of tread. A small inconsistency in one bit of the this can cause premature failure. The odds are low, but they’re there. The immediate failure would not be decompression - it hasn’t penetrated deep enough - but more likely, shredding of that part of the tyre. Which is not something you’d want happening at motorway speeds. Sorry if this doesn’t give a clear OK/not answer. You’ll have to judge whether to replace or not, given this relatively low (but not non-existent) probability. If you do, you’ll probably be advised to replace the opposite tyre as well, so that the tread depth is consistent on both sides.

 

It's hard to know what you're after Laurence. You appear to be under the impression randoms on the internet armed with a photo will be better placed to advise you than somebody hands on in KwikFit.

If you value your life and wellbeing at more than £200 or so, replace the tyre.

 

Taking the car to tyre experts tomorrow morning and will go with their advice - regardless. [BTW its Lawrence ...]
I'm grateful for the different comments (well, most of them); this is an M3 forum so posting thoughts about problems that arise seems quite reasonable. The pictures were meant to help clarify any doubt about the nature of the problem.

 

If Kwik Fit didn't want to scam a new tyre from you then, yes keep an eye on pressures for a bit.

A similar diameter screw or nail was picked up by me on a front tyre of a Ford Galaxy (having replaced all 4 not long before). That gave a slow puncture and was repaired with a (vulcanised?) plug...

Now said nail must have gone through the tread layer that's vulcanised to the carcase along with any fibre and streel layers in said carcase... No easy way to examine or see damage to those enclosed layers even with the tyre off the wheel... unless a massive hole (when a plug repair would be impossible). That repair was still all OK when I traded the car for the current EV thousands of miles later.

So I'd suggest taking such 'unseen damage' scare-mongering with a pinch of salt and see the outcome of your trusted tyre specialist's examination. Of course, if you regularly push your vehicle 'to the limit' you might wish to play safe and replace it.

 

It turns out that it was Fast-fit (local) that I visited - not Kwik-fit. My mistake. Tomorrow's booking is Kwik-fit free tyre check. [FWIW my max speed on motorways tends to average 65mph with bursts to overtake.]

 

The obvious outcome of a specific visit to a tyre specialist will be for that person to have a tooth sucking experience and recommend that you give him £250 immediately, or be ready to die on your way home.

Personally, I would be unconcerned about this incident until or unless I noticed a lower pressure in that tyre over a week. Even then, it would be a simple tyre repair - just as would have been the case if the screw had in fact penetrated a few more mm when it first happened and caused a flat.

 

Personally, I would be unconcerned about this incident until or unless I noticed a lower pressure in that tyre over a week. Even then, it would be a simple tyre repair - just as would have been the case if the screw had in fact penetrated a few more mm when it first happened and caused a flat.

+1

I had a puncture caused by a small, jagged stone that had wedged itsels between the treads and from there on it punctured the tyre. Lost air pretty quickly and I barely made it to the repair shop inflating it every 2 km. They put a patch on the inside of the tyre and that was 15k km ago. Just saying: a tyre won't blow out just because the tread has been punctured.

 

We took stuff to the local recycling centre a few days back and I have just been doing my tyre safety checks. I found a small screw - see pictures - on the rear passenger side. The screw is 13mm long and the top was flush with the tread. View attachment 214573 View attachment 214574

I got a chap at Kwik-fit to look at the tyre. He poured water over the hoel and verified that there was no bubbling. The tyre pressure seems constant. Can I assume that all is well and do another tyre pressure check ina day or two?
The tyre is a Michelin 235/45 R18 98V Extra load ST - if that tells anything useful!

It's fine. You got away with the cumulative depth of tread and carcass holding it out far enough.

It may have nicked the cords, but that is unlikely to have any effect.

Move on with life, you just used up a bit of your luck so you need to get on and go earn some more now.

No need getting it checked. But monitor tyre pressure each day for a week. Try parking 'on' that spot to make sure it does not leak when flexed. There is no point discovering a flat tyre one day when you can do without it, and finally realise you can't park on that point any more (as the tyre flexes the hole open, you see?)

 

Agree with the "don't worry, but watch the pressure" brigade, and I'm a tyre fetishist.

Blowouts are usually from driving on an underinflated tyre, or a sudden substantial impact.

If the pressure drops slowly compared to the other tyres I'd get a new one as it is right on the cusp of being repairable anyway (near the shoulder).

 

I wouldn't take it to Kwik fit, they will definitely say you need a new tyre!
Their "free" checks aren't actually free you know

 

... possibly, not even 'checks'!

 

OP's puncture is in the "major repair" zone - repair is technically possible but needs a vulcanised repair rather than standard patching which you won't get from a regular tyre shop.

Tyre Puncture Repairs - British Standard Repairs - Dexel Tyre & Auto Centre

 

OP's puncture is in the "major repair" zone - repair is technically possible but needs a vulcanised repair rather than standard patching which you won't get from a regular tyre shop.

View attachment 214617



Tyre Puncture Repairs - British Standard Repairs - Dexel Tyre & Auto Centre

I’ve never had a vulcanised tyre repair. Where do you get one?

If that involves taking the tyre off and sending it away somewhere or driving 100 miles for a repair - then most folks are just going to get a new tyre fitted without the faff.

 

I took the car along to Q/f having made an 0830am appointment. The chap took the car into the garage part and I was able to watch (almost) throughout. He jacked and then removed the wheel and took it across the floor to a wash area. After several minutes, he returned with the tyre rather wet (bubble test?) and remounted it. He reversed the car out to where I had originally left it. He came back to me, handed me the Tesla card and said that there was no problem whatsoever. The screw had not penetrated or caused any damage and it was good to go. I thanked him - of course! Yes, I am relieved that two independent tyre people have cleared it for use.
I shall continue to monitor the pressures whenever I drive and on most days regardless. Thanks to many folks here for some interesting comments and info. I had expected to pay for at least a vulcanised repair but not even that was asked for.

 

I appreciate this looks like no repair needed.
However, one more thing to take into account when talking about Tesla tyres repairs. They normally have acoustic foam inside the tyre so most garages are not too keen to repair such tyres.

 

My EV6 also has foam inside the tyres. I had a puncture repaired. They just cut out a little piece of foam where the patch goes and throw it away. The mechanic made absolutely no fuss over it.

 

Asymmetric bolt patters might be logical for some applications, actually.

 

And triangular wheels/tyres work a treat on semi-cylindrical road surfaces

(not forgetting Reuleaux wheels too!)

 

I had a similar situation on a Model 3. Tyre alerts and inflating every couple of weeks.
Took it into the local tyre repairers. He peeled back the foam, plugged the tyre and reassembled.
£32. Problem gone. No more alerts from the car.

 

Several months ago had a slow puncture on front offside on my M3. They have the foam. Took it to my local National Tyres and Autocare centre. They said they can't fix puncture on a Tesla tyre because of foam... I pointed them to various forums, including this one saying they could be repaired. Nope he wants having it.. must be a new tyre.. I can't go back there as I called him incompetent.
Went to Kwik Fit, no problem, repaired, let me watch as I said I had never seen foam inserts. He just cut out a small section where the screw had gone through. £30ish.
So I can't knock my local Kwik fit.