The rolling resistance rating that the tyre corresponds to. The higher this figure, the lower the resistance, the less fuel is spent to overcome it and the more economical the tyre is. Efficiency indices are denoted by letters of the Latin alphabet in descending order of efficiency:
A(highest efficiency),
B,
C,
D,
E,
F,
G(lowest efficiency).
With other things being equal, more economical tyres tend to cost more, but the difference is offset by fuel economy.
The average noise level created by a tyre while driving. The lower this indicator, the more comfortable this model will be, the less additional noise it will create.
Note that EU rules provide 3 categories of tyres in terms of noise.
“Quiet” are considered models with an index of up to 68 dB,
“medium” — 68 – 71 dB,
“loud” — 72 dB and above.
Tyre wear resistance rate according to the Treadwear standard issued by the US National Highway Traffic Safety Administration.
This rate indicates how far the tyre is able to travel until the tread reaches a critical level of wear. Treadwear is indicated in conditional points; formally, every 100 points correspond to 48,000 km (30,000 miles). However, it should be noted that testing according to this standard is carried out under perfect conditions — on flat roads, without numerous sharp accelerations and brakings, at a stable temperature, etc. Therefore, real wear resistance, usually, is lower by at least 20 – 30 %; and for a full guarantee, the claimed indicator is generally recommended to be divided by two. For example, formally the value of Treadwear 240 corresponds to a mileage of 48 × 2.4=115.2K km — however, in fact it is hardly worth counting on more than 90K km, and it is best to keep on the value of 55 – 58K km.
Generally, Treadwear ratings up to 250 are considered fairly low, 251 – 300 are considered average, 301 – 350 are above average, and over 350 is typical for
the most durable tyre models. Note that this characteristic is given mainly for summer, less often — all-weather tyres; winter tyres should be quite soft, which makes it difficult to achieve more or less worthy wear resistance rating.
