|Treadwear grades are an indication of a tyre's relative wear rate.The higher the treadwear number is, the longer it should take for the tread to wear down.
A control tyre is assigned a grade of 100. Other tyres are compared to the control tyre. For example a tyre grade of 200 should wear twice as long as the control tyre. Of current tyres 15% are
rated below 200, 25% are rated 201-300, 32% are rated 301-400, 20% are rated 401-500, 6% are rated 501-600 and 2% are rated above 601.
||Traction grades are an indication of a tyre's ability to stop on a wet road. A higher graded tyre should allow a car 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". Of current tyres 3% are rated "AA", 75% are rated "A", 22% are rated "B" and only 1 line of tyres are rated "C".
|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 tyres resistance to heat is grade as "A", "B" or "C". Of current tyres 27% are rated "A", 59% are rated "B" and 11% are rated "C".