Do Winter Tires Make a Difference?
A generation or two ago, when everyone was driving rear-wheel drive cars or trucks, traction control or anti-lock braking systems were unheard of, and every tire was labeled “all-season,” it was standard Minnesota practice to change to snow tires before every winter and change back in the spring. But now, with most of us in 4-wheel drive trucks or all-wheel drive SUVs with the systems as mentioned above in our cars and all-season tires on our wheels, does it still make sense to change tires for the winter? Buick GMC of Rochester is here to say “Yes” and explain why.
A common perception is that all-wheel drive or four-wheel drive increases traction, but that is not the case. A better description is that those drivetrains help make the most of the traction your vehicle has. The only objective factors involved in determining traction are the tires themselves, the amount of weight on them, and, to some degree, tire pressure. Put a set of tires with poor traction on your AWD vehicle, and you will do better than the same on a 2-wheel drive vehicle, at least in getting started, but in any transitions at speed, the result is spinning four tires instead of two.
It is also important to remember that while all-wheel drive can help you get going, it is of minor value in turning and no help at all in stopping, which are two abilities you certainly want on hand when driving in the snow. This is why, even on 2-wheel drive vehicles, it is essential to replace all four tires, not just the driving wheels.
What’s Different About Winter Tires
Most of us think of winter tires as being like all-terrain tires, with chunkier treads that can push deeper into the snow for better traction. But judging a tire for its winter use by its tread is like assuming anyone of tall stature must be good at basketball. In order of importance, these are three primary components that set winter tires apart from regular or even all-season tires:
- Rubber Composition – The colder it gets, the harder most material gets, and the harder the tire, the less traction it has. Winter tires are composed of rubber that is designed to stay soft and pliable in cold temperatures so they can maintain adequate grip and traction.
- Depth and Pattern of Tread: Winter tires have deeper tread depths than regular tires to improve traction in the snow and lessen snow buildup. It is the exact opposite of performance tires, which have limited tread depth to minimize twisting between the tire and its connection to the road surface. Winter tires also have unique tread patterns with grooves to help prevent hydroplaning by efficiently pushing moisture from the tread to the gaps in between. Pressure creates heat, so a vehicle’s weight on tires creates heat, which forms moisture on snow, and you are often driving on this layer of moisture. Left standing, this moisture will often refreeze as ice, so packed snow becomes icy.
- Tread Grooves – Unlike standard tires, winter tires will have zig-zag grooves within their tread. These grooves act as biting edges to grip the road in snow or ice.
All-season tires can approach some of these components, but they are inherently compromised because a rubber compound that must retain integrity in heat can’t be optimized for the cold. Likewise, the better a tire tread depth and design is for hot, dry surfaces, the less effective it will be in the opposite. Even when your all-season tire has a snowflake branded on the side, it only has to pass an acceleration test on medium-packed snow, which falls far short of what a dedicated winter tire can achieve. To quote Consumer Reports: “Our test-track observations lead us to advise that using snow tires provides the best grip and assurance for going, stopping, and cornering no matter what you drive: all-wheel drive, front-drive, or rear-drive.”
Timing and Cost
The best rule of thumb for when you should change to winter tires will be right in front of you. If you can see your breath, it is time to be on winter tires. While the cost of winter tires may be a concern, it is important to remember that your vehicle can only wear down one set of tires at a time. Thus, both sets will last longer. So, on the whole, you are not paying more for tires. You are just paying upfront for two longer-lasting sets, each best suited for their time of the year.
If you want to know more, our service professionals at Buick GMC of Rochester will be happy to answer any tire questions and help you determine the best winter tires for your vehicle.