Electric vehicle thread depth

This is not restricted to EV's, on the W213 E Class UK spec E220d's that came with Continental Eco Contact 6 tyres had approx 6mm thread new, same size in Pirelli was closer to 8mm

It's just that EV's tend to be heavier and more powerful, so the tyres are often wider, to give you a similar pressure over the contact patch. There's 1000 different tradeoffs in tyre design, and the stiffness of the tread block needs to work in unison with the stiffness of the sidewall, internal pressure, etc, so they've likely gone with 6mm for some good reason - likely fuel efficiency.

Car manufacturers often try to prioritise fuel efficiency (CO2 Emissions) over long term running costs, but this is especially true with EV's. 5% saving on a petrol car will bring you from 47 to 49.5MPG (6 - 5.7 [l/100km]), but in an EV it could bring you from 395 to 415km, which Has a much greater psychological impact in buyers.

Or I could be trying to explain away what is simply a marketing decision - people already accept that EV's tend to be harder on tyres, so why fight it when you can sell more tyres and blame the Greens?

I don't and have never purchased EV specific tyres. Load of nonsense for the sake of a couple of percent efficiency. I have always had 4 considerations when buying tyres.

1. Noise rating. EV, or Petrol, I hate hearing road noise. Noticed this on hard rubber ditch finders on a Zafira I bought second hand. They were new, but they were the first thing I got rid of.
2. Efficiency. B, or C is grand. A rating is a bonus. Again, petrol, Diesel or Whatever, you don't want your boots to be too sticky.
3. Brand. I stick to the ones I know in the premium, or mid-range. I stay away from economy crap. If I have to spend 150 a corner rather than 55, then so be it. Tyres are what keep you on the road, or from ploughing into the car in front, causing life long injuries. Trust me…I know.
4. Choose what I already have on the car if only changing 1, or 2 tyre. I like to keep them all the same. I might change brand/type if changing all 4. At the very least, I will choose a better pair than what is already there if for example I buy a used car which has decent rubber on the front, or back and I am changing one end.

Just buy the best you can afford. Change them before you "need" to.

https://www.tirereview.com/the-relationship-between-a-tires-tread-depth-and-rolling-resistance/

More rubber in a tire means more heat generation, higher friction and less heat dissipation, which is why increasing tread depth increases rolling resistance, and in turn, lowers fuel efficiency.

Probably tiny in real terms, the key factor in fuel consumption in the driver. They're just all rules of thumb, and can probably be reversed by making compromises in wet performance, dry performance, cost, noise, manufacturability, wear, etc.

But when a manufacturer is trying desperately to squeeze into a lower CO2 band, or 10 more kilometers of range so that they can put 400km on the advert instead of 390km, selecting a slightly different tyre is a very easy win.

What were they?

I don’t thinks it’s a rule that all EV tyres have only 6mm. Just some manufacturers are penny pinching

My anecdote… my ID.3 came with Bridgestone Turanza ECO… melted off it after 12k km’s. Put on Goodyears and getting twice the mileage. The Bridgestones had 6.x mm when new and obviously soft. The Goodyears have 7.2mm new.

Also recently bought Hankook eco tyres.. 7mm on them too and got 30k km’s from first pair. So thread depth matters but compound too.

That's great longevity on what is a big heavy and torqey beast. I must give up on the GY efficient grip I've put on the not so powerful Leaf 😀 since I got it 6 years ago. The front tyres only do about 15k to 20k km and lose serious traction below 3mm. Must have a look at my receipts and see how long the rears last but I'd be surprised if they lasted 40k km.

I have Pirelli pzero on the M3 and will keep an eye on their durability. Luckily I don't really care about road noise as the stereo is always pretty loud but I do find them much noiser than any other tyre I used previously.

Yes the traction control lights up on the least provocation on wet roads especially with lower temperatures. Back in January my tyres were below 3mm and I found them dangerous, put on new tyres and it was like night and day

One of my tyres recent failed, good brand good tread depth but 4 yrs old and a lower weight rating 92 than the others 94. When I say failed I started getting an increasing amount of vibration at slow speed. Tyre had deformed. With in a week it started to deflate over a couple of days. I've replaced all four now with a decent branded tyre.

Had no choice but to buy Chinese ditch finders on another car for the NCT. They were so bad I replaced them in a month. Like driving on ice.

You can get decent budget tyres. But trying to find tyres in stock or ordering them in seems to be much harder than it should be. I stick to tyres with good reviews now.