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Tire Talk: Get a grip on your new car’s tires

Original equipment tires favour fuel efficiency over performance, but you can demand better-quality tires while negotiating a car deal.

Published November 15, 2012

There sits your sparkling new car. It has the best of everything: airbags, stability control, ABS, lane-departure warnings, adaptive cruise control and the whole gamut of safety systems. Off you drive from the dealer’s lot and the ride is great, the car whispers down the pavement, all is bliss, life is perfect, your car is perfect.

Is it really?

When negotiating your deal, did you stop to consider what holds the whole thing on the road: the tires? Four contact patches, in total about 100 square inches (650 sq. cm.), is all that keeps you going around that curve or gets you stopped when something runs out in front of you.

Wouldn’t you like to have the absolute best 100 square inches of rubber in the world? And do you? Not likely, unless you’ve bought a high-end supercar.

But, the tires feel grippy, so they must be good. As drivers, we are blissfully unaware that our tires are losing a bit of grip every time we drive on them. Their deterioration is so slow and gradual, we learn to brake just that 1 metre earlier and drop our cornering speed just a single km/hour. This kind of adjustment becomes automatic, no thinking about it, so it’s likely that your old trade-in had pretty poor grip after four or five years of subtly slipping away.

So your new car corners like a sports car in comparison. However, on an absolute scale, the grip on OE (original equipment) tires falls below that of tires made for aftermarket sales. Auto manufacturers have to deal with government edicts called Corporate Average Fuel Economy (CAFE) standards. These fuel consumption numbers are going down each year. The easiest way to get an extra 1 or 2 kilometres per litre is to give the tires less grip.

Grip is friction. Friction takes power to overcome and that takes more gas. By giving the tire less grip, fuel economy goes up. Until recent years, this loss of grip was a given on “low friction tires.” You could have grip or fuel economy but not both, so the auto industry went for fuel economy. This is achieved through shallower tread depth, lighter-weight tires, thinner sidewalls and other shortcuts.

Automakers set criteria for rolling resistance when they source a tire for a new car. Overcoming rolling resistance uses about 15 per cent of the car’s power when going down the highway.

Tire engineers are very capable of meeting any requirement for tires, but using an unlimited amount of precious Silica in a tire — for wet grip, cooler running and lower rolling resistance — is not possible if the tire needs to meet a price point. The same holds true for other ingredients in the rubber mix. In the end, you get the best tire possible at a very low price point.

Drivers are often amazed when they buy replacement tires after the OE set wears out. They have far more grip and last longer. That reaction is common after the first tire changeover at an independent shop.

There are tires on the market that are manufactured by using greener technology with less waste.

One of the newest Yokohama tire plants produces no waste: everything that comes in the door leaves as part of a tire, except the staff. Some tires replace crude oil with organic oils, some tires even use wasted pulp from orange juice.

Michelin has a Green-X tire line certified to have the same grip levels as other tires, but needs less energy to roll down the road.

Alas, this newer generation of green tires is not cheap, so you won’t find them as OE on many new cars. The tide is shifting but, for now, look at the tires on your car selection before you sign the offer, research them and, if they’re old tech and not up to snuff, make better tires part of the purchase offer. Sure, the salesman will groan and tell you it can’t be done, but he wants you in the driver’s seat, so take control. Go green or go grippy, or go for both.

One last negotiation must take place before you buy that car: winter tires and maybe winter wheels, too. We live in Canada: it snows, it sleets, it ices, so we need winter tires. Consider asking for seasonal tire changeovers for as long as you own the car as part of the deal. Dealers always say they want you back in their service department; make them prove it. Ask for free storage of your off-season tires.

And get the winter tires when you buy the car. If you are financing the car, a set of winter tires spread out over three to five years of payments will add just a few dollars a month. It sure beats paying for everything in one pop when the snow hits.

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