TREAD DEPTH ON NEW TYRES

[r44raven]

Over the 50+ years that I have been purchasing tyres, I have never measured the tread depth on a new tyre.

Years of monitoring wear on the many/varied cars I run/have run, have seemed to confirm - as quoted by major manufacturers, and google - that new tyres arrive with between 8 and 9 mm of tread.

However, I have just purchased new Continental Ecocontact 6's for our MB A class, and was very disappointed to find the tread depth on all 4 tyres to be only 6 mm!

Historic tyre wear on our A class would translate this missing 2 mm or so of tread into around 15k miles. Naturally, I feel cheated; I have contacted Continental, but am still awaiting a response.

I'm wondering if anyone else has experienced the same?

EDIT: Following more googling, it would appear that back in 2023, Continental did reduce the new tread depth on some of their new tyres from around 8 mm to 6 mm. Before buying new tyres of any brand, I will certainly now be asking for assurances as to the tread depth I can expect!

 

[R129 UK]

Off the top of my head, I would have guessed 6mm - I've been trying to avoid buying tyres for 30+ years and I'm not aware of any publicised changes to tread depths over that time.

 

[gsxr]

Some tyres have varying tread depth across the full width of the tread surface. I recently bought a pair of Continental ExtremeContact DWS-06 Plus, size 255-40-17. One was made in late 2023 in Czech Republic, the other was from late 2022 in Brazil (strange, and not particularly fresh, but whatever).

I measured tread depth for grins and was expecting the 10/32 spec of new tires, and was confused when I measured less. Upon closer inspection, I discovered the tread depth varied substantially depending where you measured! (I forgot to write down the depth of the narrow "swoops"... oooops. These were shallower than the wide swoops.)

10/32: Wide "swoops" only!
9.75/32: Center groove only
9/32: Inner+outer grooves
6-7/32: Inner edge
5-7/32: Outer edge

I never noticed this before. IIRC, the vast majority of passenger car tires I've purchased for Mercedes cars tend to be 10/32 new tread depth. (The SUV tires on our LR4 tend to be around 12/32 new.)

 

[emerydc8]

I wonder if this is the manufacturer’s way of keeping the selling price the same (competitive) in the face of horrible inflation (money printing), like gradually making smaller packages so people don’t notice. I expect it will get worse very soon.

 

[r44raven]

Thanks for all your inputs! Obviously a subject worth keeping one's eye on. @emerydc8 may have a good point about "smaller packages" (look at any chocolate bar to see that!) - but ever the cynic, it's hard not to take the view it's a way of selling more tyres?
When tread depth (adjusting for driving style) ultimately determines the life of a tyre, why aren't manufacturers obliged to specify the tread depth on their new tyres? I've looked at the various makers' websites for the different tyres I'm currently using on my "fleet", and not one gives any indication of tread depth. However, given that most now show around 6 mm (8/32") of tread, having covered 10-20k miles, they must have started life with far more tread than the 6 mm (8/32") on my new Continentals!
I think, over the years, I've been very remiss (naive?) not to be have picked up on this before? I'd always assumed all treads are equal!

 

[gsxr]

I wonder if that's a UK thing? Tires sold in USA market almost always have a specification for new tread depth. Poke around at the Tire Rack and view the specs.

For the Eco 6, TR is showing 7/32 spec for tread depth... but TR only carries 2 sizes of that specific tire, for Maserati:

https://www.tirerack.com/tires/continental-ecocontact-6

 

[TerryA]

I just checked out Tire Rack. The Michelin AS and the Continental Summer were both 10/32” in fact everything I looked at was 10/32”

 

[doolar]

I wonder if this is the manufacturer’s way of keeping the selling price the same (competitive) in the face of horrible inflation (money printing), like gradually making smaller packages so people don’t notice. I expect it will get worse very soon.

There’s even a word for it - shrinkflation.