Mercedes Benz 2005 e 320 用户手册

Quality grades can be found, where appli-
cable, on the tire sidewall between tread 
shoulder and maximum section width. For 
example:

All passenger car tires must conform to 
federal safety requirements in addition to 
these grades.

The treadwear grade is a comparative rat-
ing based on the wear rate of the tire when 
tested under controlled conditions on a 
specified government test course. For ex-
ample, a tire graded 150 would wear one 
and one-half (1 

1

/

2

) times as well on the 

government course as a tire graded 100. 
The relative performance of tires depends 
upon the actual conditions of their use, 
however, and may depart significantly 
from the norm due to variations in driving 
habits, service practices and differences in 
road characteristics and climate.

The traction grades, from highest to low-
est, are AA, A, B, and C. Those grades rep-
resent the tire’s ability to stop on wet 
pavement as measured under controlled 
conditions on specified government test 
surfaces of asphalt and concrete. A tire 
marked C may have poor traction perfor-
mance.

200

AA

A

G

The traction grade assigned to this tire is 
based on straight-ahead braking traction 
tests, and does not include acceleration, 
cornering, hydroplaning, or peak traction 
characteristics.