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Terminology to Learn When Tyre Shopping

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When you're ready to go tyre shopping, it's good to learn some of the terminology that is used for tyres, so you can discern the best choice for your vehicle and your driving habits in particular. Buying the cheapest tyres possible may save you a few dollars initially, but these tyres may also wear out sooner than something that's a bit more expensive, and may not give you the control and handling you need when behind the wheel. To help you choose the best tyres for your car or truck, note a few terms you'll probably come across.

Aspect ratio

The aspect ratio is the measurement of the tyre's sidewall height as compared to the width of the tyre. The lower this ratio, the smaller the sidewall height of the tyre. This shorter height can make for tighter and more controlled cornering, but it also means less shock absorption from the tyre. In turn, your ride with be a bit bumpier and louder. If you drive on roads with lots of twists and turns, you'll want a low aspect ratio; otherwise, choose something in a more moderate range, so the tyres are quieter and smoother.

Load index

The load index refers to the amount of weight the tyre can safely carry when it's fully inflated. When choosing tyres, be sure you understand the pounds or kilograms indicated by the load index, as you don't simply add a zero to the load index number to come up with this weight. For example, a lightweight tyre with a load index of 71 may manage up to 761 pounds or 345 kilograms, whereas a tyre with a load index of 100 may manage 1764 pounds or 800 kilograms. Your tyre store should have a load index chart readily available, so you can opt for the right tyre according to your vehicle.

Seasonal tyres

All-season tyres may give you moderate grip and handling all year, even in rain and snow. Summer tyres will be made of a type of rubber that is less likely to wear down when driving on hot pavement. Winter tyres will look busier along the surface, as their tread will have more grooves and indentations, which are called sipes. These sipes can give you added traction in snow and on ice, but they can slow down your driving when on dry pavement. Choose an all-season tyre for everyday driving and have the winter tyres installed only when you're expecting snowfall, rather than assuming that you can drive winter tyres all year.