Buying new tires? Here’s how to make the smartest decision

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Buying new tires? Here’s how to make the smartest decision

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There are many different things to consider before buying new tires.
PHOTO: Tyler Olson, Fotolia

Switching out your winter rubbers for new all-seasons? Here are a few tips to keep in mind

By Brian Turner

Originally published: 3 hours ago

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It’s time for the annual snow to all-season tire change-over. For many of us that means purchasing some new shoes for our faithful daily driver. But with all the choices available today, what type of tire should we be choosing and from which manufacturer? Before we go shopping, here’s a quick exercise to narrow down the selection and get the best grip and performance for our dollar.

Which manufacturer to choose? If you haven’t been tire shopping in a while, you may be surprised at the number of tire manufacturers out there. There is a wide selection of new off-shore, often Asian sourced tires and while many of these don’t rate high recommendations from consumer testing organizations, they have had a positive effect on the market. Mainstream national and international brands have become extremely competitive in the face of cheaper off-shore products. When it’s you and your family’s life and safety on the line, choose wisely. Consumer Reports picked Michelin as the best brand, followed by Continental, Goodyear, and Pirelli. Tied for the fifth spot were Hankook, Cooper, Nokian, and Yokohama.

Where you drive makes a difference. You might own a rock-clearing SUV, but if you drive mainly on paved roads, choosing an aggressive treaded tire with large lugs and wide sipes (spaces between tread blocks) will mean poorer fuel mileage and a noisier, rougher ride. If you’re an urban commuter, look for tires designated as touring or highway or fuel maximizers. Today’s vehicles have shed a lot of weight and have less sound deadening material than their predecessors. Picking the wrong tire can be a noisy mistake. Since 2012, tire-makers in Europe have been required to place information labels on all their products rating them on traction, noise, and fuel efficiency. No word yet when and if these labels might appear on tires sold in Canada. If you do regularly drive on unpaved roads or off-road, you may want to consider a more aggressively treaded tire.

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Where and how you drive can affect what kind of tire you need for your car.
Minerva Studio, Fotolia

Know your size. Before you pick up the phone to your favourite tire retailer or click on a search window you’ll need to know the tire size. It’s printed on the tire sidewall and on the vehicle info-label affixed to the driver’s door or door frame. For passenger vehicles (including minivans, SUVs and light trucks) it will start with the letter “P” followed by three digits, then one or two letters, and finally two digits as in P265/65R17. If the tire size listed on your vehicle label doesn’t match what’s on the vehicle, and you haven’t bought new tires yet, you may want to find out why there’s a difference before proceeding. For a refresher, the first three digits represent the tread width of the tire in mm, the next two numbers are the aspect ratio or the height of the tire’s sidewall as a percentage of the width. So in our example of P265/65R17 the tread is 265 mm wide and the sidewall is 65% of that figure or 172.25 mm. The last two numbers (17) represent the wheel rim’s diameter in inches.

Read more: The truth on six spring driving myths and hacks

Any change you make to any of these sizes will affect the overall circumference of the tire and how it fits onto your vehicle. Keep in mind that unless you’re changing the wheel rims, you’ll have to match the last two numbers on your old tires to the new ones. In other words you can’t fit a 17-inch tire on a 16-inch or 18-inch rim.

Know your limits. Tires are also rated on their maximum speed (speed rating expressed in a letter on the sidewall) and load rating (expressed in a number). Your vehicle info-label will list the speed rating right next to the tire size. You can always increase these ratings in your new tires, but you shouldn’t install tires with a lower rating than the automaker recommends. For light truck owners that think increasing the load rating will let them carry or tow heavier loads; think again. Truck weight ratings are based on the axles and axle shaft bearings and no tires, no matter how beefy they are, can magically transform the axles into stronger units.

Also read: How to diagnose your car’s pesky squeaks and rattles

How many do you need to replace? If you’ve been rotating your tires on a regular basis (every 12,000 to 15,000 km) and your vehicle has no alignment issues, they should be worn at the same rate and therefore the answer is four. But, if not, be careful on all-wheel or four-wheel-drive vehicles. Putting on two new tires and leaving on two half-worn rubbers (or worse) can lead to driveline, axle, and transfer case problems (vibrations, not engaging AWD smoothly, etc.). And regardless of front-wheel, rear-wheel, all-wheel or four-wheel-drive, if replacing only two tires, the new ones belong on the rear. It might take more words than we have here to explain why, so check out this Michelin video for a shorter and clearer explanation.



Save with optional sizing. Once you get into tires of the 18-inch variety and larger, or tires with low profile sidewalls (aspect ratio less than 65) the prices climb and choices diminish. You may be able to select an optional size that costs less and is available from more manufacturers. The caveat here is to stay within 3 per cent of the original tires’ total circumference. You can do some size checking by web-searching for “tire size calculator” and on most of these sites if you plug in your original size and the optional size you’re considering, they will provide the overall circumference and the percentage differences. It is possible to come up with sizes that no tire maker produces, so you may need to refer to a national supplier website or your retailer for advice. If you do opt for an optional size you must replace all four tires.

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Goodyear’s Assurance ConforTred Touring all-season radial tire.
Derek McNaughton, Postmedia News

Expect more mileage from your next set of tires. A trick that auto engineers and designers use to hide noises, and improve handling is to select a soft rubber compound for the original equipment tires. These rubbers generally grip and corner well and run almost silently but in many cases seldom last past 40,000 km. Replacement tires, especially those with particularly long tread-wear warranties (80,000 km and up) are made of harder, denser materials for longer wear.
 
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