The APA places a higher priority on performance on uncleared roads over handling on dry payment, which accounts for differences between the APA’s recommendations and published reports from some other sources. The tires listed here include most of the highly rated models on the market.
If you are planning to purchase winter tires, you may want to act soon, as several tire makers are offering rebates for the purchase of four winter tires that expire in December. These are either instant rebates deducted from the invoice by the retailer, which is preferable, or mail-in rebates, or a prepaid gift card. Customers applying for a mail-in rebate usually have about a month after the deadline to send in their coupon.
APA Members in the Montreal area are eligible for a 5% pre-tax discount or a $30 after-tax rebate on any set of four tires purchased at Talon Tire in Ville Saint-Laurent.
Winter vs. All-season
The APA recommends winter tires because of their effectiveness on snow and ice. It’s unlikely that your all-season tires are adequate for winter driving in most parts of Canada, or in the U.S. snow belt. All-season tires provide modest traction on snow and ice when they are new, with grip diminishing as the tire tread wears down. The rubber compound of an all-season tire hardens as the temperature drops, providing poorer grip, even on dry surfaces. The compound of a winter tire is more pliable and retains its grip in cold temperatures.
Recently, a new class of year-round tire called All-Weather has appeared. These tires from Nokian, Toyo and Michelin, to name three brands, carry the mountain and snowflake logo that identifies them as meeting the snow tire standard, but their manufacturers also approve them for summer use. From what the APA has seen, these tires use a hybrid tread that manages to meet the winter tire traction requirement in snow, combined with the harder compound more typical of a conventional all-season tire. The compromise? Ice traction is not covered by the snow tire standard, an unfortunate ommission that the tire industry and governments should correct. On ice, the hard rubber compund of a four season tire will not equal a dedicated winter tire. If your lessor will accept them, these tires can make sense in the last year of your lease if both your winter and all-season tires are worn out. The tires in this class that the APA has the most experience with are the Nokian Hakkapeliitta WR G series tires. They performed very acceptably in our winter test, outperforming some dedicated winter tires; consumers with heavier all-wheel-drive and front-wheel vehicles report that traction is fine. The WR G4 All-Weather tire, the latest in the series, is expensive.
All-Weather tires are being promoted fairly heavily by some retailers in Pacific Coast markets like Vancouver, where ice and wet weather predominate, but roads are relatively snow-free. The tires are being recommended as equivalent to winter tires, without the hassle of semi-annual changeovers.
Four, not Two
Canadian consumers and retailers have known for many years that winter tires should be installed on all wheels. The APA occasionally receives inquiries from U.S. drivers regarding the possibity of installing two winter tires on the driving wheels, usually but not always, on the rear wheels of a rear-drive vehicle. Here’s why four winter tires are safer:
- it optimizes performance of the ABS braking and electronic stability systems
- steering is important too; with winter tires on the rear driving wheels only, the steering can “wash out”
Installing just two winter tires on the driving wheels of a front-wheel-drive vehicle is hazardous. The vehicle will appear to handle with confidence, providing all the right feedback from the driving wheels and steering until the instant the lightly-loaded rear loses traction. At highway speeds, this is can involve a rapid and vicious loss of control, with the rear of the vehicle coming around partially, and the car going off the road tail-first.
How to measure tread depth
A new winter tire is delivered with between 10/32 inch and 14/32 inch tread depth. The wear bars moulded into the voids in the tire tread indicate the absolute wear limit of 2/32 of an inch tread depth. That’s not considered safe for winter conditions. At the start of winter, experts recommend a minimum of 5-6/32 of an inch. Before installing your winter tires for another season, you can take a few minutes to measure the remaining treadlife by using a Canadian quarter with a caribou on it. Place the quarter, muzzle first, into the gap between the tire treads. If the muzzle is entirely buried, the tread measures at least 6/32nds of an inch, and is safe enough for another 10,000 kilometers. If the caribou’s muzzle is entirely visible, or the edge of the coin ahead of the muzzle is visible when inserted between the treads, the tire is likely getting close to its legal minimum tread depth of 2/32nds of an inch, and should be replaced. An expert can confirm the reading for you using a tread depth gauge, or you can purchase one yourself; they’re not expensive.
Buying an extra set of wheels for winter
Tire and wheel sizes have reached absurd proportions on new vehicles, and buying a set of smaller, ideally steel, wheels for winter is a good idea. The initial $200 to $300 outlay can be recovered over a two or three year period by eliminating the cost of seasonally mounting and removing summer and winter tires from a single set of rims. This can save over $50 each time you swap tires. In addition, steel wheels are more resistant to impacts, and better suited to corrossive winter driving environments than more fragile alloy wheels. With very large wheel sizes, your winter options may be limited to a second set of alloys.
Buying smaller diameter wheels for winter allows smaller-inside-diameter, cheaper tires to be fitted. If you do opt for a smaller diameter wheel and tire, it is necessary to maintain the same total diameter of the original equipment wheel and tire combination. Your retailer has tire guides that indicate what the appropriate substitute sizes are. For example, on a Honda Civic LX equipped from the factory with 16 inch wheels shod with 205/55R16 tires, it is possible to install 195/65R15 tires on 15 inch wheels. Savings of $80 to $300 per set of four are possible by downsizing the wheel and tire combination, depending on the vehicle.
Swapping wheels is more complicated if your vehicle is equipped with a tire pressure monitoriing system (TPMS) of the type that uses sensors mounted on each wheel (more info on this below). In that case, you may be facing the purchase of a second set of sensors and alloy wheels in a smaller size for winter. Many consumers will simply stick with the original wheels and oversized winter tires with a change-over every spring and fall.
Here is a table giving the maximum sustained speeds for tires. In North America you are unlikely to ever reach the maximum rated speed of any passenger vehicle tire, but the speed rating is also an approximate indicator of the tire’s handling ability. A winter tire rated H or higher is likely more responsive when road conditions are good, but has a tread design that will not bite as well in deep snow. The best snow tires for really bad weather are Q, R, S, or sometimes T-rated. High powered rear-wheel-drive or all-wheel-drive vehicles (Mercedes-Benz, Audi, BMW) often feel mushy on tires with low speed ratings — for those vehicles, moving down from their V or W-rated summer tires to an H-rated winter tire can be a good compromise.
|Speed code||Maximum sustained speed|
|ZR||Au delà de 300 km/h|
The rubber in all-season tires can begin to lose its elasticity in temperatures as warm as 7° C. The softer rubber compounds used in the construction of dedicated winter tires maintain their pliability, and therefore their grip, in temperatures going down to about -30° C.
Inflating a tire with nitrogen helps maintain a more conistant tire pressure because it escapes the tire more slowly than normal air (which is composed 3/4 of nitrogen), and is less affected by temperature variations. For vehicles with Tire Pressure Monitoring Systems (TPMS), filling the tires with nitrogen may reduce the incidence of false alerts during rapid changes in temperature.
It costs up to $5.00 per tire to fill it with nitrogen. To fully receive the benefits of nitrogen, the tire will have to be purged of air a couple of times before filling with nitrogen. While more stable than air, nitrogen will still leak out eventually. If a tire is low, filling it with air from a conventional compressor will negate the benefits of nitrogen. APA’s recommendation for most people: skip the nitrogen and buy a tire gauge instead and use it.
Coping with tire pressure monitoring systems (TPMS)
Increasing numbers of new vehicles are equipped with tire pressure monitoring systems (TPMS). On many systems (fortunately, not all), wheel-mounted programmable sensors transmit a signal to notify the driver when the pressure in one or more tires falls below a pre-determined threshold. Tire pressure monitors can add expense and complication to winter tire installation, especially if you have separate wheels for your winter rubber. For the TPMS to function properly, the winter wheels will need to be equipped with tire pressure sensors, which, depending on the make of vehicle, can cost anywhere from $35 to $75 per sensor. Switching over the sensors from one set of wheels to the other is discouraged to prevent sensor damage.
In many cases it is necessary to reprogram wheel-sensor-type TPMS systems during seasonal tire swaps. This can seldom be done without a special tool, and some dealers overcharge twice a year for this simple computer initialization. Independent shops now have access to programming tools to link up the vehicle with the wheel sensors; this was not the case when the APA first reviewed these systems in 2008. The more flexible TPMS systems allow the vehicle to recognize two sets of sensors without subsequent reprogramming. The least intrusive systems, like those on the majority of European luxury vehicles, dispense with wheel-mounted sensors entirely.
If you developed the good habit of regularly checking your tire pressures, you might be inclined to run your tires on winter rims without tire pressure monitoring sensors. However, putting up with a lit TPMS warning light on the dash may not be the only consequence of doing without sensors in winter. Important safety devices like the electronic stability control may be disengaged if the TPMS system is deactivated. Consult an expert before taking this step.
Decoding markings on the tire sidewall
P: this letter, which is occasionally absent, identifies the vehicle category the tire is designed for. P (for passenger) identifies that the tire is a passenger car tire. LT (for light truck), is a truck tire. AT (for all-terrain) usually an SUV tire with some off-road capability.
195: the width (in millimetres) of the tire from one side to the other. In general, it is proportional to the size and performance of a vehicle.
65: height of the tire sidewall, expressed as a percentage of the width (in this case, 65 percent of 195 mm, therefore 127 mm).
For any given width, a lower percentage of sidewall height indicates a lower profile tire.
Tires with a sidewall height 55 or less called “low profile” generally provide very good handling, occasionally at the expense of comfort. They cost much more than mainstream tires (a sidewall height of 60 to 65 or greater), and are often standard equipment on sportier cars. Low profile tires are also wrapped around large diameter wheels on high-end versions of compact and intermediate cars.
R: radial construction tire, which is virtually universal today.
15: the diameter of the wheel in inches. Fourteen inch wheels are typically reserved for the base versions of subcompact cars; 15 inch wheels are used on most compacts and on high-end versions of subcompacts; 16 inch wheels are standard on some compacts, intermediates and many compact SUVs; 17 inch wheels are found on sportier compact cars, intermediate SUVs and mid-range versions of compact SUVs; finally, 18 inch and bigger wheels are used on sporty SUVs as well as high-end versions of many cars. Wheels with a diameter greater than 16 inches are rarely needed on a touring car, but have become fashion items over the last decade.
91: index of the maximum permissible load. For example, an index of 91 notes that the tire can support up to 615 kg (1356 lb.). Never install tires that have a lower index than that noted in the owner’s manual.
Q: speed rating. Indicates the maximum speed the tire can roll safely for an extended period, assuming that it is in good condition and inflated to the pressure recommended by the manufacturer of the car it is installed on. For example, a Q-rated tire corresponds with a maximum speed of 160 km/h. Winter tires for touring cars and SUVs are seldom rated higher than a T (190 km/h).
The M+S (Mud + Snow) legend indicates that the tire has wider than normal gaps between the treads than a summer tire. As there is no industry standard to define what M+S means, the level of traction in winter conditions is variable.
D): Snowflake inside a mountain pictogram.
All winter tires offered in Canada bear this symbol that denotes approval of the Canadian Rubber Association (CRA). In principle, it guaranties that the tire conforms to specific performance requirements regarding grip in snow, and that the tire is specifically designed for driving in snowy conditions. The standard does not currently include a test for traction on ice. Until recently, the snowflake on a mountain symbol was a reliable indicator that a tire really was suitable for a Nordic winter, but that is no longer always true. The standard needs to evolve so the winter tire designation doesn’t lose its significance, like the M+S All Season designation did.