Why winter tires are necessary over all-season tires in cold climates?
All-season tires aren’t really for all seasons. Those tires work for most drives, but as soon as the temperature nears freezing, the advantages of having winter tires make the additional cost and effort worth it. According to a recent winter tire test report, it became evident to this tire novice just how big the gap is between all-season and winter tires when freezing temperatures come into play.
Testing Winter Tires vs. All-Season Tires on Ice
Having the chance to test-drive all-season tires and winter tires on slippery and icy surfaces back to back gave me a lot of perspective on the advantages of winter tires and why they’re worth it. The test mules were a pair of new Toyota RAV4 XLE AWD models fitted with a set of name-brand all-season tires and a set of name-brand winter tires.
AWD (All-Wheel Drive) is key here; many drivers believe that having a vehicle equipped with AWD is sufficient to deal with snow, slush, and ice. But I would soon find out that even an AWD vehicle equipped with all-season tires would quickly reach its limits when put in a dynamic situation in inclement winter weather. Testing consisted of driving on ice and performing three different, seemingly innocuous tasks: accelerating over a 60-foot span, braking to a halt from 12 mph, and navigating a corner at 11 mph.
Acceleration Test on Ice
The results of the 60-foot acceleration portion were similar, since the AWD (All-Wheel Drive) system did much of the hard work, with times coming in at 3.7 seconds for the all-season tire versus 3.1 seconds for the winter tire. Driving impressions between the two small SUVs varied, though, with lots of wheel spin off the line on the all-season tires, whereas the winter tires seemed to pick up speed quickly.
Braking Test On Ice
But it was the braking portion where the winter tires really outperformed the all-seasons. Braking from 12 mph down to a complete stop resulted in lots of ABS modulation for the vehicle equipped with all-season tires—with a stopping distance of 57 feet. The winter tire provided more grip, which allowed the ABS to do its job, stopping the RAV4 in just 34 feet. Given that it took an extra 1.5 car lengths to stop from just 12 mph, just think of the extrapolated stopping distances at boulevard or highway speeds. What’s more, stopping the RAV4 shod with all-season tires felt violent as the ABS engaged more often, compared to the winter-tire car, which was more composed under full brake.
Cornering Test on Ice
The cornering test consisted of a 90-degree turn at a steady 11 mph. The winter-tire-equipped vehicle made the turn without losing traction. The car with the all-season tires lost traction and wanted to plow straight ahead—even after the stability control system kicked in and tried unsuccessfully to change the course. It was alarming to note the immediate loss of traction at such a slow cornering speed; the all-season tire simply gave up without much effort.