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and wheels checked ataqualified specialist
workshop.
When parking your vehicle,makesure that
thetires do notget deformed by the curb or
other obstacles. If it is necessary to drive over
curbs, speed humps or similar elevations, try
to do so slowly and at an obtuse angle.
Otherwise, the tires, particularly the
sidewalls, may be damaged.
Regular checking of wheels and tires
GWARNING
Damaged tires can cause tire inflation
pressure loss. Asaresult, you could lose
control of your vehicle. There isarisk of
accident.
Check the tires regularly for signs of damage
and replace any damaged tires immediately.
Regularly checkthe wheels and tires of your
vehicle for damage at least onceamonth, as
well as after driving off-road or on rough
roads. Damaged wheels can causealoss of
tire pressure. Pay particular attention to
damage such as:
Rcuts in the tires
Rpunctures
Rtears in the tires
Rbulges on tires
Rdeformation or severe corrosion on wheels
Regularly check the tire tread depth and the
condition of the tread across the whole width
of the tire (Ypage 335). If necessary, turn
the front wheels to full lock in order to inspect
the inner side of the tire surface.
All wheels must haveavalve cap to protect
the valve against dirt and moisture. Do not
mount anything onto the valve other than the
standard valve cap or other valve caps
approved by Mercedes-Benzfor your vehicle.
Do not use any other valve caps or systems,
e.g. tire pressure monitoring systems.
Regularly check the pressure of all the tires
particularly prior to long trips. Adjust the tire
pressure as necessary (Ypage 338).
Observe the notes on the emergencyspare
wheel (Ypage 367).
The service life of tires depends, among other
things, on the following factors:
RDrivingstyle
RTire pressure
RDistance covered
Important safety notes on the tire
tread
GWARNING
Insufficient tire tread will reduce tire traction.
The tire is no longer able to dissipate water.
This means that on wet road surfaces, the risk
of hydroplaning increases, in particular where
speed is not adapted to suit the driving
conditions. There isarisk of accident.
If the tire pressure is too high or too low, tires
may exhibit different levels of wear at
different locations on the tire tread. Thus, you
should regularly check the tread depth and
the condition of the tread across the entire
width of all tires.
Minimum tire tread depth for:
RSummer tires: in (3 mm)
RM+S tires: in (4 mm)
For safety reasons, replace the tires before
the legally prescribed limit for the minimum
tire tread depth is reached.
Operation335
Wheels and tires
Z
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Example:
RTreadweargrade:200
RTractiongrade:AA
RTemperature grade:A
All passengercar tires must conform to the
statutory safety requirements in additionto
these grades.
iTheactual values for tires arevehicle-
specificand maydeviate from the values in
the illustration.
Treadwear
The treadweargrade isacomparative rating
based on the wearrate of thetirewhen tested
undercontrolled conditions onaspecified
U.S. government course. For example,atire
graded 150 would wear one and one-half
times as well on the government course as a
tire graded 100.
The relative performanceoftires 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 conditions.
Traction
GWARNING
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.
!Avoid wheelspin. This can lead to damage
to the drive train.
The traction grades, from highest to lowest,
are AA, A, B, and C. Those grades represent
the tire's ability to stop onawet surface as
measured under controlled conditions on
specified government test surfaces of asphalt
and concrete.Atire markedCmay have poor
traction performance.
The safe speed onawet, snowcovered or icy
road is always lower than on dry road
surfaces.
You should pay special attention to road
conditions when temperatures are around
freezingpoint.
Mercedes-Benzrecommendsaminimum
tread depthof in(4mm)onall four winter
tires. Observe the legally required minimum
tire tread depth (Ypage335). Winter tires can
reduce the braking distance on snow-covered
surfaces in comparison with summer tires.
The braking distance is still much further than
on surfaces that are not icy or covered with
snow. Take appropriate care when driving.
Further informationonwinter tires (M+S
tires) (Ypage336).
Temperature
GWARNING
The temperature grade for this tire is
established foratire 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 areA(the highest),
B, and C. Theserepresent the tire's
resistancetothe generationofheat and its
ability to dissipate heat when tested under
controlled conditions onaspecified indoor
laboratory test wheel. Sustained high
temperature can cause the material of the tire
to degenerateand reduce tire life, and
excessive temperature can lead to sudden
tire failure. The gradeCcorresponds toalevel
of performancewhich all passenger car tires
must meet under the Federal Motor Vehicle
Safety Standard No. 109. GradesBand A
represent higher levels of performanceonthe
laboratory test wheel than the minimum
required by law.
350All about wheelsand tires
Wheels and tires
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Curbweight
The weight ofavehicle with standard
equipment includingthemaximum capacity
of fuel, oil and coolant.Italso includes the air-
conditioningsystem and optional equipment
if these are installed in the vehicle, but does
not include passengers or luggage.
Maximumload rating
The maximum tireload is the maximum
permissible weight in kilograms or lbs for
whichatireisapproved.
Maximumpermissible tirepressure
Maximum permissible tirepressure for one
tire.
Maximumload on one tire
Maximum load on one tire. This is calculated
by dividingthe maximum axle load of one axle
by two.
PSI (pounds per squareinch)
Astandardunitofmeasure for tire pressure.
Aspect ratio
Relationship between tire height and tire
width in percent.
Tirepressure
This is pressure inside the tire applying an
outward forcetoeach square inch of the tire's
surface. The tire pressure is specified in
pounds per square inch (psi), in kilopascal
(kPa) or in bar. The tire pressure should only
be corrected when the tires are cold.
Cold tirepressure
The tires are cold:
Rif the vehicle has been parked without
direct sunlight on the tires for at least three
hours and
Rif the vehicle has been driven for less than
1mile (1.6 km).
Tread
The part of the tire that comes intocontact
with the road.
Bead
The tire bead ensures that the tire sits
securely on the wheel. There are several steel
wires in the bead to preventthe tire from
comingloose from the wheel rim.
Sidewall
The part of the tire between the tread and the
bead.
Weight of optional extras
The combined weight of those optional extras
that weigh more than the replaced standard
parts and more than 2.3 kilograms (5 lbs).
These optional extras, such as high-
performance brakes, level control,aroof rack
orahigh-performancebattery, are not
included in the curb weight and the weight of
the accessories.
TIN (Tire Identification Number)
This isaunique identifier which can be used
byatire manufacturer to identify tires, for
example foraproduct recall, and thus identify
the purchasers. The TIN is made up of the
manufacturer's identity code, tire size, tire
type code and the manufacturing date.
Load bearing index
The load bearing index (also load index) is a
code that contains the maximum load bearing
capacity ofatire.
Traction
Traction is the result of friction between the
tires and the road surface.
Treadwear indicators
Narrow bars (tread wear bars) that are
distributed over the tire tread. If the tire tread
is level with the bars, the wear limit of in
(1.6 mm) has been reached.
356All about wheels and tires
Wheels and tires