Better tires for winter, same range

We are now entering our second year iX propertywhich means the start of our second winter with the car. Last year, we got through the winter without any problemsbut the car never felt particularly comfortable in low-grip conditions. So this was at the top of my list of things to take care of before the snow starts flying this year.

The iX comes standard with all-wheel drive thanks to its dual-motor setup. This is a huge advantage when the roads are covered in snow, but the BMW still has substantial advantages against low-grip driving. The biggest problem? Weight. THE iX weighs about 5,700 pounds, and even the most advanced stability control and braking systems can’t compensate for the mass.

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The other big problem was the tires. Goodyear Eagle Touring all-season tires provide a good blend of grip, low noise and low rolling resistance for daily driving. However, in tougher conditions they were consistent but less than brilliant. I wanted something a little more confidence inspiring.

I faced a similar situation with our previous EV, a Tesla Model Yby opting for a set of dedicated snow tires for the winter months. With the iX, I hoped to avoid having to change wheels and tires twice a year.

When I heard about the Nokian Remedy WRG5, it seemed like a perfect solution. Nokian calls it an “all-weather” tire, something perfectly enjoyable to drive all year round on wet or dry roads. But it offers a more aggressive tire compound and tread to deal with the types of low-traction conditions that Nokian winter tires are known for.

The Nokian (left) compared to the Goodyear (right)

The company was kind enough to offer a set for testing, but there was one problem: Nokian doesn’t make a Remedy WRG5 in the 235/60R20 size that the iX xDrive50 rides on by default. The closest was the 255/55R20, significantly wider and slightly shorter.

Knowing that the iX was designed for tires as wide as 275 for the M60 version, I knew that fitting tires with a width of 255 sections would be no problem in the fenders. There is also concern that a wider tire may actually be worse for grip in winter, as the conventional wisdom is that narrow tires are better. However, tire engineers have assured me in the past that in most non-racing situations a wider tire is always better, even in a low-grip environment.

So I placed the order, and indeed, the tires fit on the iX without problem. What was surprising was how much wear the original Goodyear tires had. The two rear wheels were noticeably more worn than the front wheels, not to the point where they needed to be replaced, but certainly to the point where much of their finer tread was gone. My tread gauge shows that there was about 1/4 inch of tread remaining after 7,500 miles. Most experts recommend replacing tires as soon as they drop below 4/32 of an inch in rainy or winter conditions. So it’s not nice to see them so worn after just a year of driving.

Old tires. You can see that the rear tires (left) were considerably more worn than the front tires (right), probably because the iX sends more power to the rear wheels.

This is despite the fact that this thing is primarily driven for casual commuting and relaxed road trips. In fact, BMW doesn’t have a recommended tire rotation interval, but if you have a jack and the required tools, I might suggest doing it every 5,000 miles or so.

Regardless, given the reduction in tread on both of these tires, I was happy to swap for the more aggressive Nokians before the snow started flying.

Noise and range

Beyond the size issues, I was also concerned that these additional sipes would cause more noise on dry asphalt. So I took some recordings of the car with the old tires before swapping them. On the same stretch of dry asphalt, the Nokians systematically measured to within one decibel that of Goodyears.

And then there’s the question of scope. A more winter-friendly tread and tire compound will surely result in lower efficiency, right? The first tests actually indicate the opposite. On a 220-mile highway test loop, the iX actually used slightly less energy than when running the Goodyears on days with similar temperatures (between 40 and 50 degrees F), i.e. averaging 2.7 miles per kWh on Nokians and 2.6 on Nokians. Happy years.

Real-world range tests like this are inconsistent at best, so I’m not going to say that the Nokians are actually more effective. However, it allayed my concerns about the 10-15% range decrease I had seen in the past when using a dedicated snow tire.

Finally, I was also a little worried about how far away the speedometer would be, given that the outer diameter of the new tires is slightly smaller than the old ones. I had done the math using online calculators, but was very pleased to find that the difference measured by GPS at highway speed was less than 1 mph.

Restart

While we were doing all of this testing, we noticed something was wrong with the iX: the hands-free professional driver assistance system wasn’t working. It didn’t give any errors or throw any alerts, it just didn’t work on the highway.

We also noticed that the car refused to accept remote commands. The iX had previously proven inconsistent in handling preconditioning requests or providing information on state of charge, etc. But now the thing was dead to the world as far as the MyBMW app was concerned.

Photo by: InsideEVs

The iX’s software experience is generally good, but it’s not perfect.

I was a little worried that there was a problem with the car’s onboard modem, but after some Googling, my wife read that other people were solving similar situations by forcing the SUV to restart. The process isn’t as simple as the three-finger salute Windows users are familiar with for restarting, but it’s close: press the engine start/stop button three times to enter diagnostic mode, then hold the button down. volume button for 30 seconds.

Moments later the car was back online and happily cruising down the highway hands-free.

Now it’s time to see how the new tires hold up to the white stuff – assuming we get any this year.