Mercedes-Benz 2009 CL-Class Operator's Manual page 450

Operation
Tires and wheels
service practices and differences in road
characteristics and climate.
Traction
G Warning!
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.
The traction grades, from highest to lowest,
are AA, A, B, and C. Those grades represent
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 performance.
G Warning!
If ice has formed on the road, tire traction
will be substantially reduced. Under such
weather conditions, drive, steer and brake
with extreme caution.
The safe speed on a wet, snow covered or icy
road is always lower than on a dry road.
You should pay particular attention to the
condition of the road whenever the outside
temperature is close to the freezing point.
448
Mercedes-Benz recommends winter tires
( Y page 452) with a minimum tread depth of
1
approximately / in (4 mm) on all four wheels
6
for the winter season to ensure normal
balanced handling characteristics. On
packed snow, they can reduce your stopping
distance compared to summer tires.
Stopping distance, however, is still
considerably greater than when the road is
not covered with snow or ice. Exercise
appropriate caution.
! Avoid spinning of a drive wheel. This may
cause serious damage to the drivetrain
which is not covered by the Mercedes-Benz
Limited Warranty.
Temperature
G Warning!
The temperature grade for this tire is
established for a tire that is properly
inflated and not overloaded. Excessive
speed, underinflation, or excessive loading,
either separately or in combination, can
cause excessive heat build-up and possible
tire failure.
The temperature grades are A (the highest),
B, and C, representing the tire's resistance to
the generation of heat and its ability to
dissipate heat when tested under controlled
conditions on a specified indoor laboratory
test wheel. Sustained high temperature can
cause the material of the tire to degenerate
and reduce tire life, and excessive
temperature can lead to sudden tire failure.
The grade C corresponds to a level of
performance which all passenger car tires
must meet under the Federal Motor Vehicle
Safety Standard No. 109. Grades B and A
represent higher levels of performance on the
laboratory test wheel than the minimum
required by law.
Tire ply material
Plies in sidewall
1
Plies under tread
2