282 Operation
Tires and wheels
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.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.
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.
283 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
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
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
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.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
287 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 261).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 261).
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 362).
!A wheel change should only be carried out
at an authorized Mercedes-Benz Center. Other-
wise there is a danger of damaging the vehicle by
jacking it up incorrectly.
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
95 lb-ft (130 Nm).
Only use Genuine Mercedes-Benz wheel
bolts specified for your vehicle’s rims.
288 Operation
Tires and wheels
Anti-theft wheel nuts
Your vehicle is equipped with anti-theft
wheel nuts that prevent the theft of your
vehicle’s wheels.
1Anti-theft wheel nut
2Wheel nut keyRemoving anti-theft wheel nuts
Unscrew anti-theft wheel nut1 using
wheel nut key2.
Replace anti-theft wheel nut1 with
one of the regular wheel bolts.
Fasten the wheel bolt and tighten it
with a torque wrench to a tightening
torque of 95 lb-ft (130 Nm).Warning!G
Pull the parking brake lever up as many
notches as possible and move the gear se-
lector lever to park positionP, before loos-
ening the wheel bolts. Otherwise the vehicle
may move and cause an accident and/or
serious personal injury.
!Do not use air tools, such as an impact
wrench, when installing or removing the
anti-theft wheel nuts. An impact wrench can
damage the anti-theft wheel nuts and the wheel
nut key, or cause them to malfunction.
!Store wheel bolts and anti-theft wheel nuts
not currently in use in a safe place to avoid
damage to the threads.
Warning!G
The wheels could come loose if the wheel
bolts are not tightened to a torque of 95 lb-ft
(130 Nm). Have the tightening torque
checked after changing a wheel.
289 Operation
Tires and wheels
Fitting anti-theft wheel nuts
Unscrew a wheel bolt from one of the
wheels.
Replace that wheel bolt with one of the
anti-theft wheel nuts1 delivered with
your vehicle.
Fasten anti-theft wheel nut1 using
wheel nut key2 and tighten with a
torque wrench to a tightening torque of
95 lb-ft (130 Nm).
Warning!G
The wheels could come loose if the wheel
bolts are not tightened to a torque of 95 lb-ft
(130 Nm). Have the tightening torque
checked after changing a wheel.
iKeep the anti-theft wheel nut key in a conve-
nient place in your vehicle where you and service
personnel can always find it easily when it is
needed.
iIf you should lose the anti-theft wheel nut
key or one of the anti-theft wheel nuts, please
contact an authorized Mercedes-Benz Center for
a replacement.
290 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 below freezing
temperatures (
page 397).
Battery test. Battery capacity drops
with decreasing ambient temperature.
A well charged battery helps to make
sure that the engine can be started,
even at low ambient temperatures.
Tire change. Mercedes-Benz recom-
mends M+S rated radial-ply tires with a
minimum tread depth of approximately
1/6in (4 mm) on all four wheels for the
winter season.
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 Can-
ada (RAC) and have been designed specif-
ically for use in snow conditions. Use of
winter tires is the only way to achieve the
maximum effectiveness of the ABS and
ESP
® in winter operation.
For safe handling, make sure that 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
vehicle, you must place a notice to this
effect where it will be seen by the driver.
Such notices are available from your tire
dealer or from any authorized
Mercedes-Benz Center.
!A wheel change should only be carried out
at an authorized Mercedes-Benz Center. Other-
wise there is a danger of damaging the vehicle by
jacking it up incorrectly.
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.
295 Operation
Vehicle care
Vehicle care
Cleaning and care of the vehicle
If you have any questions about proper
care of your SLR, please contact an
authorized Mercedes-Benz Center.Depending on body color the characteris-
tic carbon structure of the body surface
may become visible due to high ambient
temperatures and humidity. This phenom-
enon is related to the technology and
concept of the vehicle’s body.
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
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 elimi-
nates 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.
Warning!G
Many cleaning products can be hazardous.
Some are poisonous, others are flammable.
Always follow the instructions on the partic-
ular 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.
iMercedes-Benz recommends that you use
Mercedes-Benz care products. These have been
specially developed to suit Mercedes-Benz vehi-
cles and are state of the art. Mercedes-Benz
care products are available from any
Mercedes-Benz Center.
!Affixing stickers, magnets, adhesive tape or
similar materials to painted body components
may damage the paintwork.
297 Operation
Vehicle care
Power washer
Cleaning the windows and wiper blades
Remove the SmartKey from the starter
switch.
Fold the wiper arm away from the
windshield (
page 361).
You must feel the wiper arm engage in
position.
Clean the wiper blade inserts with a
clean cloth and detergent solution.
Use a soft, clean cloth and a mild win-
dow cleaning solution on all outside
and inside glass surfaces.
An automotive glass cleaner is
recommended.Cleaning the headlamps
Wipe the headlamp lens with a damp
sponge.
!Do not use power washer to clean your
vehicle or the engine.
!The hood must be opened (page 250) be-
fore folding the wiper arm away from the wind-
shield. You could otherwise damage the hood
and/or the wiper arms.
!Never open or close the hood when the wip-
er arms are folded away from the windshield.
You could otherwise damage the hood and/or
the wiper arm.
Warning!G
For safety reasons, switch off wipers and
remove SmartKey from starter switch
before cleaning 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.
!To clean the window interior, do not use a
dry cloth, abrasives, solvents or cleaners con-
taining 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.
!Fold the windshield wiper arms back onto
the windshield before turning the SmartKey in
the starter switch.
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.
!Only use windshield washer fluid suitable
for plastic lamp lenses. Unsuitable windshield
washer fluid may cause damage to the plastic
lenses of the headlamps.
Do not use
a dry cloth
abrasive products
solvents
cleaning agents containing solvents
You could otherwise scratch or damage the lens
surface.