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Winter tires not only offer good grip on slick surfaces but perform better on dry roads when it's cold (below 7C).
Replace tires on front or rear first?
Why new tires should go on the rear if you're only replacing two tires
By Bill Roebuck
Research shows it's best to replace all four tires at once, but if you can only afford two, which wheels should they go on -- front or rear?
If only two tires are installed, whether they are all-season, winter or rain tires, research indicates its safest to put them on the rear position, as this gives the best lateral control, especially in corners. This fact holds true for all vehicles, including rear-wheel drive, front-wheel drive and four-wheel drive models.
Logically, you might think it's best to put them on the front drive wheels of a front-wheel drive car, but that's not the case, as it's safer to have increased lateral grip on the rear. You can usually regain control of slipping front tires by lifting off the accelerator, but if the rear end breaks loose, you're in for a spin and possibly a crash.
The rear tires of any vehicle must have comparable or higher traction capabilities than the front tires in order to optimize vehicle mobility and control, especially during sudden manoeuvres, according to Cooper Tires.
Cooper states: "If winter/snow tires are applied to the front axle of any vehicle, winter/snow tires must also be installed on the rear axle. DO NOT apply winter/snow tires only to the front axle. This applies to all passenger and light truck vehicles including front-wheel-drive, 4WD, and AWD vehicles. WARNING! Without winter/snow tires on the rear axle, which have comparable traction qualities to the tires on the front axle, the vehicle may experience adverse handling characteristics. This may result in loss of vehicle control, which could cause serious injury or death."
Want proof? Watch this video for a comparison of having new tires on the front and worn tires on the rear, and vice versa.
Running only two winter tires can cause you to lose control of any vehicle. Here's why, according to the staff at Discount Tire of Scottsdale, AZ:
Front-Wheel Drive Vehicles: Even though the front wheels are responsible for steering, acceleration and most of the braking, don't forget about the braking done by the rear wheels. If the rear wheels are not equipped with winter tires too, you are essentially disabling the rear brakes due to lack of traction. The following is an example of what can happen using only winter tires on the front.
Travelling along in your neighbourhood at 25 mph in just light snow, you begin to slow down to make a right turn. As you apply the brakes, your winter tires are doing their job, giving you all the traction you need to slow down. At the same time, the all-season tires on the rear are giving you much less traction causing the rear of your vehicle to slide around. Perhaps at slow speeds no harm is done, but what if this had occurred at highway speeds?
Rear-Wheel Drive Vehicles: Many people think that winter tires on the rear will solve the acceleration problem in ice and snow. However, getting your vehicle to accelerate is only half the battle, because you still need to stop. The majority of braking is done with the front brakes, and failing to put tires designed for cold weather on the front of the vehicle can have disastrous consequences. Also, keep in mind that steering is the sole function of the front tires. With insufficient traction on the front tires, it's like not being able to firmly grasp the steering wheel.
Now that you know this, how confident would you feel if your vehicle was equipped with only rear winter tires? What if you were driving on snow, ice, or even cold pavement at 45 mph and suddenly had to brake and swerve to avoid an accident? Chances are you would be unable to stop and turn in time.
All-Wheel Drive or Four-Wheel Drive Vehicles: During the winter you would never purposefully disconnect your four-wheel drive and use just two-wheel drive instead. Yet that is exactly what you are doing if you use just two winter tires. The traction mismatch basically disconnects the two other wheels not equipped with winter tires. This leaves you open to the control problems cited in the other two sections, depending upon where you mount the winter tires.
Also avoid mixing tires with different tread patterns and wear.
All said, it's still best to replace four tires at a time, no matter what kind. Having different sets of tires on front and rear axles may cause one end of the vehicle to lose traction before the other in a turn, especially where the pairs have different tread patterns or traction characteristics. In terms of winter braking, four all-season tires may be good, two of each may be better, but the best is still four matched winter tires.
Note that you can probably get a set of four winter tires on steel rims for your vehcile for about $700 or so, depending on your model. Considering that your summer tires will also last longer if you switch tires every year, it's a small investment to make for greater safety.
Posted Oct. 26, 2009. © CarTest.ca.