A very common question we get during the Fall and Winter seasons is whether someone needs four winter tires, or if they can get away with two. The simple fact is that installing two winter tires on any vehicle is quite dangerous.
You are probably better off not installing any. If a rear-wheel drive vehicle has two snow tires installed in the rear, you’ll certainly be able to get moving a lot easier. But what happens when you need to steer, or stop? You have tires on the front of the car that may not be up to the task. If a front-wheel drive vehicle has winter tires installed only on the front, it is very easy for the rear of the car to lose traction going around a corner, or under braking, which can lead to oversteering (fishtailing). Winter tires are so much more capable than the snow tires of yesteryear, and grip so much better; it is not a good idea to install only a pair.
This leads into another area, which is four-wheel drive. Of course, four-wheel drive will help any vehicle, regardless of tires, to get moving more easily in inclement weather. You have twice as many tires clawing at the ground than normal. However, once you stop accelerating, and start to coast, or brake, or turn… Four-wheel drive is doing absolutely nothing for you other than being a few hundred more pounds to bring to a halt. This is where having a winter tire on the vehicle becomes a very good idea.
This question comes up every fall, and is posed by a great number of our customers, especially living in a relatively mild winter city such as Vancouver.
The question is; do they need winter tires? Before I give my opinion, I’ll explain the advantages and disadvantages of each.
There are some common myths about winter tires. They are now called “winter tires”, and not “snow tires” for good reason. They are designed to work in climates based on temperature… Not based on precipitation. The magic number used in the industry is 7*C (or 45*F). Check out our Winter Tire Guide for a visual chart. This is the temperature in which the rubber compound in a winter tire starts to work much better than an all season compound. The compound in the winter tire is engineered to remain soft and supple, even in very cold temperatures. Regardless of weather conditions, all things being equal, a winter tire will provide better grip levels than an all season tire in temperatures under 7*. The all season compound tends to become more stiff and hard in the cold, and therefore does not grip the road as well, even in dry conditions. The colder it gets, the more evident this becomes.
The one disadvantage to using these soft rubber compounds in the winter tires, is they should not be used in warm weather, or else the tire wears very quickly. This is why winter tires are only recommended for cold weather use, and why a second set of tires becomes necessary for the summer months. It is important to note there is no safety issue with using a winter tire in the summer, only a premature wear issue. It is much better in my opinion, from a safety standpoint, to use a winter tire in warmer weather than to use a summer or all-season tire in cold weather.
If you look at the actual tread of a winter tire and an all–season tire, you will notice the winter tire has many more small “cuts” in it. These little cuts are called “sipes.” The sipes make the rubber tread block more flexible, which makes the tire more capable of providing grip in snowy or icy conditions. The sipes give the tire many more biting edges to grip and grab ice or snow. Some winter tires even have zigzag shaped sipes to give as many biting surfaces as possible. An all season tire does not have these sipes, at least not nearly to the extent as a full on winter tire.
Really, it is up to the end consumer to decide if winter tires are worth it to them. Of course the initial expense is higher than running an all-season year round, but since you have two sets of tires, they are each going to last twice as long so the end price is very similar. The difference in performance between a winter tire and an all-season tire in winter conditions is very substantial. It’s one of those things you don’t really believe or understand until you see it for yourself. I recommend to 90% of my customers that winter tires really are a good idea, even for only a moderately cold climate. They provide peace of mind along with simply being the right tool for the job.