Tire testing inside the chamber. Click image to enlarge
Article and photos by Jil McIntosh
Florida winter tire testing
Fort Walton Beach, Florida – It’s a beautiful day on the Florida panhandle. It’s some 35 degrees Celsius, the palm trees are swaying gently in the breeze, and people are swimming in the ocean. In short, the ideal spot to test winter tires by driving them in the snow.
Yes, you read that right. I’m in Florida to check out a winter tire. As odd as it may seem, this is the perfect place, since it’s the home of the McKinley Climatic Laboratory, located on Eglin Air Force Base. I’m here for the premiere of Goodyear’s new Ultra Grip Ice WRT, a dedicated winter tire made specifically for trucks and SUVs. And I’m standing in the world’s largest climatic chamber, which has been cooled to minus 9 degrees Celsius, with snow and ice thrown in.
While it’s used primarily for military testing, the laboratory also rents out its facilities to various automobile, tire and aircraft manufacturers. It’s not only capable of producing cold, but also extreme heat, rain, dust storms and other nasty weather. It may seem strange to pay for manufactured indoor weather when the real thing can be available for free outside, but the key to accurate testing is the consistency that the laboratory can create. Without fluctuations in temperature or precipitation, tests can be performed over and over, even on different days, without any of the variables that will be present outdoors.
A traction truck is used to measure wheel spin (top); The Ultra Grip Ice has a unique pattern for trucks (middle); The traction truck uses electric motors to spin the rear wheels. Click image to enlarge
Goodyear wasn’t actively testing the tire during my visit, but I did get some insight into some of the specialized trials that go into the engineering of such products. The company had brought along one of the three “traction trucks” it owns. When the driver flicks a switch, electric motors on the rear wheels spin the tires – again, more consistently through repeated tests than even a skilled driver could do on his own. The cab is filled with data-collection equipment, which deciphers the information on tire grip and slippage, and prints it out for the engineers to study.
All of this is important because winter tires aren’t just “snow” tires anymore. They also provide superior grip on cold, dry pavement. That’s significant, since many areas in Canada don’t see as much snowfall and accumulation as they once did. Rubber tends to get hard when it’s cold and soft when it’s hot – exactly the opposite of what you want a tire to do, and so tire companies are constantly working to upgrade their rubber compounds so they stay pliable and grippy when it’s cold, and firmer and less likely to be squirmy when it’s hot. So-called “all-season” tires are a compromise between the two, with a relatively narrow window where their performance is top-notch. At only plus 7 degrees Celsius, their grip on dry pavement is inferior to that of a dedicated winter tire.
The Ultra Grip Ice WRT, made in two tread patterns specifically for light trucks or SUVs and crossovers, marks Goodyear’s first application of its new Winter Reactive Technology, hence the name. This is a combination of a sticky winter grip rubber compound, a directional tread design, and new designs in the “blades,” the grooves in the tread. In the centre, the blades open when they make contact with the pavement, increasing the gripping area for better starting and stopping ability. On the tire’s shoulder, the blades use a design the company calls Tredlock Technology: on turns, they lock together, providing lateral strength and grip. The right blend of stickiness and stability, along with an aggressive tread for channelling slush and water, are keys to a good winter tire.