Should tyres have DOT code visible?

[sat1983]

Just had mine fitted but two of them haven't got DOT code visible? Have those been fitted incorrectly?

[paintman]

Not necessarily.
Usually on one sidewall.
No requirement for it to be on the outside when fitted to the car.
https://btmauk.com/2021/01/26/dot-code-celebrates-...

If the tyres have a directional tread there will be a direction of rotation marked on a tyre then that should be observed.

Edited by paintman on Friday 26th November 23:41

[Pica-Pica]

If two have the DOT code showing and two do not, it is possible they may be fitted the wrong way round. Are they all the same make? Are they directional tyres? If so there should be an arrow showing the direction of rotation. Or are they asymmetric tyres? If so, they should have OUTER on the outside.

[sat1983]

Pica-Pica said:

If two have the DOT code showing and two do not, it is possible they may be fitted the wrong way round. Are they all the same make? Are they directional tyres? If so there should be an arrow showing the direction of rotation. Or are they asymmetric tyres? If so, they should have OUTER on the outside.

Same make (Pirelli's), they are directional tyres. The arrow does show the correct direction of rotation- just found it odd that two of them didn't show the DOT code...

[paintman]

As they are directional tyres which have to be fitted accordingly you will find the two on one side of the car will have the code visible and the two on the other side won't.

As explained in the link the code is only on one side of the tyre not both.

Get under the car - or take a wheel off on the side where you can't see the code - look at the wall of the tyre and you'll find the code.

Or take it back to the place that fitted them and ask them to show you.

Edited by paintman on Saturday 27th November 09:59

[d_a_n1979]

IIRC ALL tyres will have the DOT code on one of the sidewalls; it could be that they're on the inside of the tyre

[sat1983]

paintman said:

As they are directional tyres which have to be fitted accordingly you will find the two on one side of the car will have the code visible and the two on the other side won't.

As explained in the link the code is only on one side of the tyre not both.

Get under the car - or take a wheel off on the side where you can't see the code - look at the wall of the tyre and you'll find the code.

Or take it back to the place that fitted them and ask them to show you.

Edited by paintman on Saturday 27th November 09:59

Thanks- that explained it clearly.

Also directional tyres have a V tread pattern- noticed these were all ok and do have the distinct V shape. So all ok! DOT code 2421

[Pica-Pica]

sat1983 said:

Thanks- that explained it clearly.

Also directional tyres have a V tread pattern- noticed these were all ok and do have the distinct V shape. So all ok! DOT code 2421

OK. All fine. I still can’t believe a DOT code would not be on both sides of a directional tyre, not exactly consumer friendly.

[paintman]

"The Tire Identification Number is moulded into the tyre when it is cured. Consistent with its original purpose, the full code is only marked on one sidewall. The UK tyre market is supplied from factories all over the world. To put the date code on both sidewalls would require agreement between the international regulatory authorities and add considerable complexity to the tyre curing process in factories worldwide."

From the link.
Appears to be in the 'too difficult' tray.
And perhaps 'How much extra would you like to pay for your tyres?'