What a snow test showed
Edmunds tested the same Honda Civic Si on groomed snow at a proving ground in northern Minnesota, with ABS and traction control on. Each figure is the average of the middle three of five runs. On the factory all-season tires the car needed 184 feet to stop from 40 mph. On winter tires of the same size it stopped in 156 feet, and on narrower winter tires in 147 feet, about 20% shorter. Summer performance tires needed 351 feet, almost twice the all-season distance.
Show the data
| Tires | Feet |
|---|---|
| Winter, narrower 205/55R16 | 147 |
| Winter, 215/45R17 | 156 |
| All-season, 215/45R17 | 184 |
| Summer, 215/45R17 | 351 |
Acceleration told the same story: 0 to 40 mph took 14.5 seconds on all-season tires and 11.0 to 11.7 seconds on winter tires. It is one car and one test, but the direction matches what tire makers and testers report again and again: on snow, the tire matters more than anything else on the car.
Why the difference is so large
Winter tires use a softer rubber compound that stays flexible in freezing weather, deeper tread and many small slits (sipes) that bite into snow and ice. Tire Rack notes that ultra high performance summer tires turn almost like hard plastic below freezing. All-season tires sit in the middle: they are designed for long, even wear, not for winter grip.
All-wheel drive does not change this. It helps you get moving, but every car stops and steers with the same four contact patches. ABS and traction control do not add grip either; they only manage the grip the tires already have.
How to read the sidewall
- M+S (mud and snow) is based only on tread pattern. It makes no promise about how the tire performs in snow, and most all-season tires carry it.
- Three-peak mountain snowflake (3PMSF) means the tire passed a standard packed snow acceleration test set by the US and Canadian tire industry associations, scoring about 10% or more above a reference tire. The test does not measure braking, cornering or ice.
- Every winter tire carries the 3PMSF symbol, but not every 3PMSF tire is a winter tire. Many all-weather tires carry it too. They are a step up from ordinary all-season tires and can be kept on all year, but Tire Rack says they are not a substitute for dedicated winter tires where winters are harsh.
Always fit four
Tire Rack says all of its tire makers and 7 out of 10 vehicle makers recommend four winter tires. In its test of a front-wheel drive Toyota Camry with winter tires on the front and all-season tires on the rear, braking and acceleration were close to a full winter set, but in corners the rear end began to slide out as speed rose, the kind of skid that can turn into a spin. Mixed tires give the car a split personality, so buy and fit them as a set.
Do you need them?
- Yes, if you live in the snow belt, drive on unplowed or hilly roads, or cannot stay home when it snows.
- Probably not, if snow is rare where you live. Tire Rack says that in places on the edge of the snow belt, such as Seattle, Memphis or Atlantic City, fairly new all-season or all-weather tires will probably be fine.
- In between: a 3PMSF all-weather tire is a reasonable middle ground if you do not want to swap tires twice a year.
Tread still matters. NHTSA says tread should be at least 2/32 inch on every tire (if a penny placed head down in the groove shows the top of Lincoln’s head, it is time for new tires), and that you should check pressure when tires are cold, since pressure drops as temperatures fall. Worn all-season tires are the worst case in snow. Our guide shows when to replace tires.
Make the swap easy
Many owners keep winter tires on a second set of wheels, which makes the twice a year change quicker. Ask your shop to note the tire positions so the set can be rotated next season. Log each swap and the mileage in Badger’s maintenance schedule, so you know how many miles each set has done and when it is time to change back.
