Tire shopping can be confusing. The most popular tire size in the UK is 205/55 R16, but if you search for this on any online tire retailer, you get presented with a myriad of options.
205/55 R16 91T, 205/55 R16 91H, 205/55 R16 91V, 205/55 R16 91W, 205/55 R16 91Y, 205/55 R16 94H XL, 205/55 R16 94V XL, 205/55 R16 91W XL.
It's common knowledge all these tire sizes exist, but it's less known that they could all be exactly the same tires.
With the introduction of the Michelin CrossClimate and Pilot Sport 4, Michelin will now only be making the highest load and speed rating version of the tire, meaning in the above example, the produced tire would be the 205/55 R16 94V XL, which would be suitable for any 205/55 R16 fitment.
The benefit to retailers and the supply chain is huge. Instead of having to stock eight different tires, they can now stock one, and it makes shopping for tires online a whole lot easier for the consumer too. But what about any negative aspects of using the higher load and speed rated tire on a vehicle originally specified with a lower option?
The Law and Insurance
Legally, and from an insurance standpoint, you're absolutely fine using a higher load and speed rating. The law says your tires must at least meet the minimum load rating, so if a car is specified with 91 rated tires, 91, 94 and 98 are all fine. Speed rating is even less strict, with cars specified with 91V summer tires often specifying 91H winter tires.
The other potential negative aspect of using a higher rated tire is a loss of comfort, extra noise and reduced MPG due to weight, but fortunately in the real world the difference is negligible, or often nothing.
For the Michelin Primacy 3 in 205/55 R16, the 91V version of the tire weighs 8.948kg, while the 94V XL version weighs in at 8.964kg, just 16g heavier, which will be unnoticable from a fuel consumption and comfort / noise point of view.
Michelin are doing an interesting job trying to simplify the world of tire shopping, and if other manufacturers follow suit, the entire supply chain from production to a customer having the tires fitted is about to become a whole lot simpler.
But the example's not the highest speed rating of those mentioned (Y), or even those for the 94 load index (W)!
It's not something Michelin are doing for selling a more "expensive" tire. It is purely to try and simplify the process, for us, dealers and consumers. It's actually meaning we risk losing sales, especially if a dealers screen searching for a 91V doesn't see the 94V we make. But we feel making so many options with minimal differences just over complicates things
It's my understanding from tire load charts that XL rated tires require a slightly higher pressure to reach the same load capacity as a non XL tire. Take the above example that the 91V tire with recommended pressure of 33psi, would need to be replaced with a 94V tire with 35psi. Taken that the vast majority of road users run underinflated anyway, I wonder if this would be any safety issue for a fully loaded car driven long distance, heat for example?
Not really for absolute majority of cases, and specially not in winter...All new cars have TPMS pressure leak sensors and the difference of 2 psi is negligible. Plus the new tire compounds are much less heated when rolling than previous generations. Howgh.
It's quite complex and depends a bit upon the legislation required by the ETRTO regs
Simply run the pressures for a standard tire in an XL tire
The addition of a slightly higher pressure for max loading on an XL is almost like a double safety element
It ensures that XL tires can take extra load even in some cases where the construction of the tires aren't significantly different
Most road cars have tires that are way over the maximum weight of the car laden so if the tires are at the recommended pressures they'll cope with the load very easily
My car requires 225/45/R17 91Y tires. It's currently fitted with Goodyear Eagle F1 Asy3's, and when I was last shopping for tires 225/45/R17 94Y were also available but a couple of quid more expensive per corner. The cynic in me thinks that this is probably at least part of their motivation.
Interesting you are using speed index Y, because it means your car has Vmax=271-300 km/h... But though in some EU countries you can save your money by using lower speed index (W,V,H, even T means cheaper tires) for winter tires when you put in front of the driver (or as a limit alert in your board computer) a sticker with that lower max. speed. The question is if it is authorised also in the UK and for all season tires, which I don't know.
P.S. Newest UK all seasons tire test is from the Auto Express magazine testing 17” size, 225/45R17: And the winners are...
You are allowed to use a lower speed rating in the UK, but NOT a lower load rating than specified.
Interesting you are using speed index Y, because it means your car has
Vmax=271-300 km/h... But though in some EU countries you can save your
money by using lower speed index (W,V,H, even T means cheaper tires) for
winter tires when you put in front of the driver (or as a limit alert
in your board computer) a sticker with that lower max. speed. The
question is if it is authorised also in the UK and for all season tires,
which I don't know.
P.S. Newest UK all seasons tire test is from the Auto Express magazine testing 17” size, 225/45R17: And the winners are...
My Honda FRV has traction control called VSA.
In the manual it says that you must fit 205/55 R16 91V not 94V for the traction control to work.
We fitted 4 x Crossclimate 94V to our car last year and have noticed a few more traction control events since. Is this a coincidence?
If you are fitting four, it's more likely to be coincidence. Whilst calibration of most Traction control systems is integral within the ECU, e.g. suffice to the car having the same tires all round most systems will learn and adapt
I'm happy to help (I'm Technical Engineer for Michelin UK) if there's anything else we can do
One wonders if there will still be, say, 3 versions of a 94V though - with different qualities across the parameters of tire performance (especially for different markets around the world). So, one 94V optimised for wet grip, another for rolling resistance & comfort, another for longevity & impact resistance & so on. If so, then, nice though the standardization of 94V would be, it would not be one tire & would still be a "lucky (or unlucky) dip" as to what variant one was getting if it were to be opaque (as in current practice) just what variant had what performance parameter profile.
My issue is not with the variants' existence so much as the near total lack of information as to the comparative properties of the variants (even, in my experience, when one asks a company's "front desk" tech people (they don't know & can't access answers).
No premium tire manufacturer would bring different tuned versions of the tire to the same market without OE marking them.
We believe this problem has only arisen in the past when tire dealers import tires illegally from different markets in order to buy them cheaper.