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Treadwear
Treadwear grades are an indication of a tyre's wear rate. The higher the treadwear number, the longer it takes for the tread to wear down.
A ‘standard' control tyre is assigned a grade of 100. The treadwear rate of all test tyres is compared to the ‘standard' tyre. For example, a tyre grade of 200 should wear twice as long as the control tyre. Treadwear grades are tested under controlled conditions using four vehicles fitted with test tyres that run in convoy. The vehicles repeatedly run a specified 640 kilometre road course for a total of 11,520 kilometres. Tread depths are measured every 1,280 kilometres and the measurements for each vehicle are averaged to give a projected wear-out life.
Traction
Traction grades are an indication of a tyre's ability to stop in the wet. A higher grade should allow your vehicle to stop on wet roads in a shorter distance than a tyre with a lower grade. Traction is graded from highest to lowest as AA, A, B and C.
Temperature
Temperature grades are an indication of a tyre's resistance to heat. Sustained high temperature (for example, driving long distances in hot weather), can cause a tyre to deteriorate, leading to blowouts and tread separation. From highest to lowest, a tyre's resistance to heat is graded A, B or C.
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Treadwear grades are tested under controlled conditions
using four vehicles fitted with test tyres that run in convoy.
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