356 Operation
Tires and wheels
Uniform Tire Quality Grading Standards
(U.S. vehicles)
Tire manufacturers are required to grade
tires based on three performance
factors: treadwear, traction and
temperature resistance.
1Treadwear
2Traction
3Temperature resistanceQuality 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.
Treadwear
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.
Traction
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
performance.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
TreadwearTractionTemperature
200AAA
Warning!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.
357 Operation
Tires and wheels
Temperature
The temperature grades are A (the high-
est), B, and C, representing the tire’s resis-
tance 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 tem-
perature can cause the material of the tire
to degenerate and reduce tire life, and ex-
cessive 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 Mo-
tor 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
1Plies in sidewall
2Plies under tread
This marking tells you about the type of
cord and number of plies in the sidewall
and under the tread.
Warning!G
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underin-
flation, or excessive loading, either sepa-
rately or in combination, can cause
excessive heat build-up and possible tire
failure.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
361 Operation
Tires and wheels
Rotating tires
Tire rotation can be performed on vehicles
with tires of the same dimension all
around. If your vehicle is equipped with
tires of the same dimension all around,
tires can be rotated, observing a
front-to-rear rotation pattern that will
maintain the intended rotation (spinning)
direction of the tire (
page 334).
In some cases, such as when your vehicle
is equipped with mixed-size tires (different
tire dimension front vs. rear), tire rotation
is not possible.If applicable to your vehicle’s tire configu-
ration, tires can be rotated according to
the tire manufacturer’s recommended in-
tervals in the tire manufacturer’s warranty
pamphlet located in your vehicle literature
portfolio. If none is available, tires should
be rotated every 3 000 to 6 000 miles
(5 000 to 10 000 km), or sooner if neces-
sary, according to the degree of tire wear.
The same rotation (spinning) direction
must be maintained (
page 334).
Rotate tires before the characteristic tire
wear pattern becomes visible (shoulder
wear on front tires and tread center wear
on rear tires).
Thoroughly clean the mounting face of
wheels and brake disks, i.e. the inner side
of the wheels/tires, during each rotation.
Check for and ensure proper tire inflation
pressure.For information on wheel change, see the
“Practical hints” section (
page 422) and
(
page 452).
Warning!G
Rotate front and rear wheels only if the tires
are of the same dimension.
If your vehicle is equipped with mixed-size
tires (different tire dimensions front vs.
rear), tire rotation is not possible.
Warning!G
Have the tightening torque checked after
changing a wheel. Wheels could become
loose if not tightened with a torque of
80 lb-ft (110 Nm).
Only use Genuine Mercedes-Benz wheel
bolts specified for your vehicle’s rims.
362 Operation
Winter driving
Before the onset of winter, have your
vehicle winterized at an authorized
Mercedes-Benz Center. This service
includes:
Check of anticorrosion and antifreeze
concentration.
Addition of cleaning concentrate to the
water of the windshield and headlamp
cleaning system. Add MB Concentrate
“MB SummerFit” to a premixed wind-
shield washer solvent/antifreeze
which is formulated for temperatures
below freezing point (
page 496).
Battery test. Battery capacity drops
with decreasing ambient temperature.
A well charged battery helps to make
sure the engine can be started even at
low ambient temperatures.
Tire change.
Winter tires
Always use winter tires at temperatures
below 45°F (7°C) and whenever wintry
road conditions prevail. Not all M+S rated
tires provide special winter performance.
Make sure the tires you use show the
mountain/snowflake.marking on the
tire sidewall. These tires meet specific
snow traction performance requirements
of the Rubber Manufacturers Association
(RMA) and The Rubber Association of
Canada (RAC) and have been designed
specifically for use in snow conditions. Use
of winter tires is the only way to achieve
the maximum effectiveness of the ABS and
the ESP
® in winter operation.
For safe handling, make sure all mounted
winter tires are of the same make and have
the same tread design.Always observe the speed rating of the
winter tires installed on your vehicle. If the
maximum speed for which your tires are
rated is below the speed rating of your ve-
hicle, you must place a notice to this effect
where it will be seen by the driver. Such no-
tices are available at your tire dealer or any
authorized Mercedes-Benz Center.
Warning!G
Winter tires with a tread depth of less than 1/6in (4 mm) must be replaced. They are no
longer suitable for winter operation.
363 Operation
Winter driving
Block heater (Canada only)
The engine is equipped with a block
heater.
The electrical cable may be installed at an
authorized Mercedes-Benz Center.
Snow chains
Snow chains should only be driven on
snow-covered roads at speeds not higher
than 30 mph (50 km/h). Remove chains
as soon as possible when driving on roads
without snow.
Please observe the following guidelines
when using snow chains:
Using snow chains is not permissible
with all wheel/tire combinations
(
page 482).
Use snow chains in pairs and on rear
wheels only. Follow the manufacturer's
mounting instructions.
Only use snow chains that are
approved by Mercedes-Benz. Any
authorized Mercedes-Benz Center will
be glad to advise you on this subject.
Use of snow chains may be prohibited
depending on location. Always check
local and state laws before installing
snow chains.
Do not use snow chains on the spare
wheel (
page 482).
Warning!G
If you use your spare tire when winter tires
are fitted on the other wheels, be aware that
the difference in tire characteristics may
very well impair turning stability and that
overall driving stability may be reduced.
Adapt your driving style accordingly.
Have the spare tire replaced with a winter
tire at the nearest authorized
Mercedes-Benz Center.!Some tire sizes do not leave adequate clear-
ance for snow chains. To help avoid serious dam-
age to your vehicle or tires, make sure the use of
snow chains is permissible as specified in the
“Technical data” section of this Operator’s Man-
ual, see “Rims and tires” (
page 482).
!If snow chains are mounted to the front
wheels, they may scrape against the body or axle
components. The tires or the vehicle could be
damaged as a result.
iWhen driving with snow chains, you may
wish to deactivate the ESP® (page 94) before
setting the vehicle in motion. This will improve
the vehicle‘s traction.
CLK 63 AMG:
Do not switch off the ESP
® when driving in snow
or with snow chains mounted.
367 Operation
Vehicle care
Vehicle care
Cleaning and care of vehicle
Regular and proper care will help to
maintain the value of your vehicle. The
best way to protect your vehicle from
harmful environmental influences is to
wash it and use protective treatments
regularly.While in operation, even while parked, your
vehicle is subjected to varying external
influences which, if gone unchecked, can
attack the paintwork as well as the vehicle
underbody and cause lasting damage.
Such damage is caused not only by
extreme and varying climatic conditions,
but also by:
Air pollution
Road salt
Tar
Gravel and stone chipping
To avoid paint damage, you should
immediately remove:
Grease and oil
Fuel
Coolant
Brake fluid
Bird droppings
Insects
Tree resins, etc.Frequent washing reduces and / or
eliminates the aggressiveness and
potency of the above adverse influences.
More frequent washings are necessary to
deal with unfavorable conditions:
near the ocean
in industrial areas (smoke, exhaust
emissions)
during winter operation
You should check your vehicle from time to
time for stone chipping or other damage.
Any damage should be repaired as soon as
possible to prevent corrosion.
In doing so, do not neglect the underbody
of the vehicle. A prerequisite for a
thorough check is a washing of the
underbody followed by a thorough
inspection. Damaged areas need to be
re-undercoated.
Your vehicle has been treated at the
factory with a wax-base rustproofing in the
body cavities which will last for the lifetime
of the vehicle. Post-production treatment Warning!G
Many cleaning products can be hazardous.
Some are poisonous, others are flammable.
Always follow the instructions on the
particular container. Always open your
vehicle’s doors or windows when cleaning
the inside.
Never use fluids or solvents that are not
designed for cleaning your vehicle.
Always lock away cleaning products and
keep them out of reach of children.
373 Operation
Vehicle care
Cleaning the windows and the wiper
blades
Make sure the hood is fully closed.
Make sure the vehicle’s on-board
electronics have status0 (
page 38).
Fold the wiper arms forward until they
snap into place.
Clean the wiper blade inserts with a
clean cloth and detergent solution.
Use a soft, clean cloth and a mild
window cleaning solution on all outside
and inside glass surfaces.
An automotive glass cleaner is
recommended.
!Do not apply strong pressure to the sensor
covers. Applying strong pressure may damage
the sensor covers.
Follow the instructions provided by the power
washer manufacturer on maintaining a distance
between the vehicle and the nozzle of the power
washer.
!To prevent scratches, never apply strong
force and only use a soft, non-scratching cloth
when cleaning the sensors. Do not attempt to
wipe dirty sensors with a dry cloth or sponge.
!Never open the hood when the wiper arms
are folded forward.
Warning!G
For safety reasons, switch off wipers and
remove SmartKey from starter switch
(vehicles with KEYLESS-GO*: Make sure the
vehicle's on-board electronics have
status0) before cleaning the windshield
and/or the wiper blades. Otherwise, the
wiper motor could suddenly turn on and
cause injury.
!Do not pull on the wiper blade inserts. They
could tear.
!Fold the windshield wiper arms back onto
the windshield before turning the SmartKey in
the starter switch or pressing the KEYLESS-GO
start/stop button (vehicles with KEYLESS-GO*).
Hold on to the wiper when folding the wiper arm
back. If released, the force of the impact from
the tensioning spring could crack the windshield.
!To clean the window interior, do not use a
dry cloth, abrasives, solvents or cleaners
containing solvents. Do not touch the inside of
the front, rear or side windows with hard objects
such as an ice scraper or ring. Doing so may
damage the windows.
374 Operation
Vehicle care
Chrome-plated exhaust tip*
Regular cleaning and care of chrome-plat-
ed exhaust tips will help to maintain their
shine and the classy appearance.
Use Mercedes-Benz approved Chrome
Polishing Paste each time the vehicle
has been washed, especially during the
winter.Light alloy wheels
If possible, clean wheels once a week.
Use Mercedes-Benz approved Wheel
Care, a soft bristle brush and a strong
spray of water for cleaning the light
alloy wheels.Plastic and rubber parts
Use a gentle dishwashing detergent or
mild detergent for delicate fabrics as a
washing solution.
Wipe with a cloth moistened in a
lukewarm solution.
The surface may temporarily change
color. If this is the case, wait for it to
dry.
!Do not use alkaline cleaners such as wheel
cleaners as they could cause corrosion.
!Only use acid-free cleaning materials. Acid
may cause corrosion or damage the clear coat.
!The vehicle should not be parked for an
extended period of time immediately after it has
been cleaned, especially not after the wheel rims
have been cleaned with wheel rim cleaner.
Wheel rim cleaners can lead to increased
corrosion of the brake disks and brake pads.
Non-approved wheel cleaners may also damage
the wheel paint if the car is not driven after
cleaning. Therefore, the vehicle’s brake system
should always be warmed-up before it is parked
after cleaning. To do so, please drive your vehicle
for several minutes to allow the brakes to dry.
When applying Mercedes-Benz approved Tire
Care and Mercedes-Benz approved Wheel Care
products, take care not to spray them on the
brake disks.
Warning!G
Do not use cleaners or cockpit care sprays
containing solvents to clean the cockpit or
the steering wheel. Cleaners containing sol-
vents will make the surface porous and vehi-
cle occupants could suffer serious injuries
from plastic parts coming loose in the event
of air bag deployment.