Toyo’s walnut-infused tires are cracking just fine on ice
Small fragments of nut’s shell give added grip
Who knew walnut shells were one of the hardest natural fibres in the world? Hard enough, in fact, that they can be made — and I’m not kidding about this — to act as studs in your snow tires. I didn’t.
Indeed, when I heard Toyo tires was making specific performance claims for their walnut infused — and, yes, it does sound like something you’d order at a French restaurant where the waiter talks out of his nose — GSi5 tires, I decided to look into those assertions. It turns out that walnut shells are around three to four on the Mohs hardness scale ( invented by Friedrich Mohs in 1812, which compares the hardness of materials to diamonds and talc and are frequently used instead of sand to blast paint and rust off delicate car parts.
Essentially what Toyo Microbit Technology does is grind up walnut shells and dumps them into the batter that makes up the rubber compound used in the tread of its GSi5 winter snow tires. The idea is that the sharp edges protrude from the rubber and, as the tires wear, more traction-garnering walnut shells are uncovered, so they might grip the slipperiness that is winter.
In pure snow conditions, the walnut shells have relatively little effect. In these conditions, the Toyos are good to excellent snow tires. Not quite the Hakkapeliittas that are the kings of the fluffy stuff, but no worse than your average Michelin or Bridgestone snow tires. Where the GSi5s really come into their own, however, is on sheer ice or when there is some hardpacked snow underneath a layer of fluffiness. In these conditions, their tread pattern matters less than those walnut “studs” and those pointy shells really do make a difference.
We did some side- by- side acceleration and braking tests with identical vehicles comparing the GSi5 tires with Michelin’s already excellent X- Ice tires and, in each case, the Infiniti QX30s accelerated harder and braked faster with the Toyos than they did with the French rubber. The difference was not overwhelming: about half a car length up to 80 kilometres an hour and a few metres when we braked back to a standstill. However, their advantage was consistent.
More importantly, since the whole point of winter tires is getting those last few metres of traction — which can be a the difference between an oopsy and a “wow, we missed that by inches” — the Toyos proved their worth. I was skeptical that a nut could make the difference, but since the Republicans are insisting their new leader will do just that ...
Anyway, if your daily drive in the winter sees a lot of ice underfoot, Toyo’s walnut tires are a cut above. The GSi5 tire is available in more than 100 sizes, from 155/ 80R13 (with a suggested list price of $ 118) to some monster 315/ 35R20s that cost $ 665. The 235/50R18s I tested had a list price of $363 each.