276 OperationDriving instructions
TiresTread wear indicators (TWI) are required by
law. These indicators are located in six
places on the tread circumference and be-
come visible at a tread depth of approxi-
mately
1⁄16 in (1.6 mm), at which point the
tire is considered worn and should be re-
placed.
The tread wear indicator appears as a solid
band across the tread.
Warning!
G
To reduce the risk of personal injury as a re-
sult of inadvertent vehicle movement, be-
fore turning off the engine and leaving the
vehicle always:
Keep right foot firmly on brake pedal.
Firmly depress parking brake pedal.
Move the gear selector lever to
position
P.
Slowly release brake pedal.
When parked on an incline, turn front
wheels towards the road curb.
Turn the SmartKey to starter switch
position
0 and remove, or press
KEYLESS-GO* start/stop button (vehi-
cles with KEYLESS-GO*).
Take the SmartKey or the SmartKey with
KEYLESS-GO* with you and lock vehicle
when leaving.
Warning!
G
If you feel a sudden significant vibration or
ride disturbance, or you suspect that possi-
ble damage to your vehicle has occurred,
you should turn on the hazard warning flash-
ers, carefully slow down, and drive with cau-
tion to an area which is a safe distance from
the road.
Inspect the tires and the vehicle underbody
for possible damage. If the vehicle or tires
appear unsafe, have it towed to the nearest
Mercedes-Benz Center or tire dealer for re-
pairs.
Warning!
G
Although the applicable federal motor vehi-
cle safety laws consider a tire to be worn
when the tread wear indicators (TWI) be-
come visible at approximately
1/16in
(1.6 mm), we recommend that you do not al-
low your tires to wear down to that level. As
tread depth approaches
1/8in (3 mm), the
adhesion properties on a wet road are
sharply reduced.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
277 Operation
Driving instructions
Specified tire pressures must be main-
tained. This applies particularly if the tires
are subject to extreme operating condi-
tions (e.g. high speeds, heavy loads, high
ambient temperatures).Hydroplaning
Depending on the depth of the water layer
on the road, hydroplaning may occur, even
at low speeds and with new tires. Reduce
vehicle speed, avoid track grooves in the
road and apply brakes cautiously in the
rain.
Tire traction
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
temperatures are close to the freezing
point.Mercedes-Benz recommends 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 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 ap-
propriate caution.
Warning!
G
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
may lose control of the vehicle. Continued
driving with a flat tire or driving at high
speed with a flat tire will cause excessive
heat build-up and possibly a fire.
Warning!
G
If ice has formed on the road, tire traction
will be substantially reduced. Under such
weather conditions, drive, steer and brake
with extreme caution.
278 OperationDriving instructionsTire speed rating
Regardless of the tire rating, local speed
limits should be obeyed. Use prudent driv-
ing speeds appropriate to prevailing condi-
tions.CLK 320
Your vehicle is factory equipped with
“H”-rated tires, which have a speed rating
of 130 mph (210 km/h) or with “W”-rated
tires*, which have a speed rating of
168 mph (270 km/h).
An electronic speed limiter prevents your
vehicle from exceeding a speed of
130 mph (210 km/h).
CLK 320 with Appearance Package*
Your vehicle is factory equipped with
“W”-rated tires, which have a speed rating
of 168 mph (270 km/h).
An electronic speed limiter prevents your
vehicle from exceeding a speed of
130 mph (210 km/h).CLK 500
Your vehicle is factory equipped with
“Y”-rated tires, which have a speed rating
of 186 mph (300 km/h).
An electronic speed limiter prevents your
vehicle from exceeding a speed of
130 mph (210 km/h).
CLK 55 AMG
Your vehicle is factory equipped with
“Y”-rated tires, which have a speed rating
of 186 mph (300 km/h).
An electronic speed limiter prevents your
vehicle from exceeding a speed of
155 mph (250 km/h).Warning!
G
Even when permitted by law, never operate
a vehicle at speeds greater than the maxi-
mum speed rating of the tires.
Exceeding the maximum speed for which
tires are rated can lead to sudden tire fail-
ure, causing loss of vehicle control and pos-
sibly resulting in an accident and/or
personal injury and possible death, for you
and for others.
iFor information on tire speed rating for
winter tires, see “Winter tires”
(page 300).
296 OperationTires and wheels
Tires and wheelsSee your authorized Mercedes-Benz
Center for information on tested and rec-
ommended rims and tires for summer and
winter operation. They can also offer ad-
vice concerning tire service and purchase.Retreaded tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on
retreads. Mercedes-Benz can therefore
not assure the operating safety of the vehi-
cle when such tires are used.Warning!
G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. See your authorized
Mercedes-Benz Center for further informa-
tion. If incorrectly sized rims and tires are
mounted:
The wheel brakes or suspension compo-
nents can be damaged.
The correct operating clearance of the
wheels and tires is no longer guaran-
teed.
Warning!
G
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can re-
sult in the bolts loosening and possibly an
accident.
297 Operation
Tires and wheels
Important guidelines
Only use sets of tires and rims of the
same type and make.
Tires must be of the correct size for the
rim.
Break in new tires for approximately
60 miles (100 km) at moderate
speeds.
Regularly check the tires and rims for
damage. Dented or bend rims can
cause tire pressure loss and damage
the tire beads.
If vehicle is heavily loaded, check tire
pressure and correct as required.
Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths under
1/8in (3 mm).
When replacing individual tires, you
should mount new tires on the front
wheels first (on vehicles with
same-sized wheels all around).
Life of tires
The service life of a tire is dependent upon
various factors including but not limited to:
Driving style
Tire pressure
Distance driven
Direction of rotation
Unidirectional tires offer added advantag-
es, such as better hydroplaning perfor-
mance. To benefit, however, you must
make sure the tires rotate in the direction
specified.
An arrow on the sidewall indicates the in-
tended direction of tire rotation.
Warning!
G
Tires and spare tire should be replaced after
six years, regardless of the remaining tread.!Keep unmounted tires in a cool, dry
place with as little exposure to light as
possible. Protect tires from contact
with oil, grease and gasoline.
298 OperationTires and wheelsChecking tire inflation pressure
Correct the tire pressure only when tires
are cold.
Regularly check your tire pressure at inter-
vals of no more than 14 days.
If the tires are warm you should only cor-
rect the tire pressure if it is too low for cur-
rent operating conditions.
A table on the fuel filler flap lists the spec-
ified tire inflation pressures for warm and
cold tires as well as for various operating
conditions.Tire pressure changes by approximately
1.5 psi (0.1 bar) per 18°F (10°C) of air
temperature change. Keep this in mind
when checking tire pressure where the
temperature is different from the outside
temperature.
Tire temperature and tire pressure are also
increased while driving, depending on the
driving speed and the tire load.Check the spare tire periodically for condi-
tion and inflation. Spare tires will age and
b e c o m e w o r n o v e r t i m e e v e n i f n e v e r u s e d ,
and thus should be inspected and replaced
when necessary.Warning!
G
If the tire pressure drops repeatedly:
Check the tires for punctures from for-
eign objects.
Check to see whether air is leaking from
the valves or from around the rim.
iThe pressures listed for light loads are
minimum values offering high driving
comfort.
Increased inflation pressures listed for
heavier loads may also be used for light
loads. These higher pressures produce
favorable handling characteristics. The
ride of the vehicle, however, will be
somewhat harder. Never exceed the
max. values or inflate tires below the
min. values listed in the fuel filler flap.
Warning!
G
Follow recommended inflation pressures.
Do not overinflate tires. Overinflating tires
can result in sudden deflation (blowout) be-
cause they are more likely to become punc-
tured or damaged by road debris, potholes,
etc.
Do not underinflate tires. Underinflated tires
wear unevenly, adversely affect handling
and fuel economy, and are more likely to fail
from being overheated.
Do not overload the tires by exceeding the
specified vehicle capacity weight (as indicat-
ed by the label on the pillar in the driver’s
door opening). Overloading the tires can
overheat them, possibly causing a blowout.
299 Operation
Tires and wheels
Rotating wheels
On vehicles with the same wheel size all
around, wheels can be rotated every 3 000
to 6 000 miles (5 000 to 10 000 km), or
sooner if necessary, according to the de-
gree of tire wear. The same direction of tire
rotation must be retained.Rotate the wheels before the characteris-
tic tire wear pattern becomes visible
(shoulder wear on front wheels and tread
center wear on rear wheels).
Thoroughly clean the inner side of the
wheels after each rotation. Check and en-
sure proper tire inflation pressure.Warning!
G
Rotate front and rear wheels only if they are
of the same size.
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.
300 OperationWinter driving
Winter drivingBefore the onset of winter, have your vehi-
cle winterized at an authorized
Mercedes-Benz Center. This service in-
cludes:
Check of anticorrosion and antifreeze
concentration.
Addition of cleaning concentrate to the
water of the windshield and headlamp
cleaning system. Add MB Concentrate
“S” to a premixed windshield washer
solvent / antifreeze which is formulated
for temperatures below freezing point
(page 416).
Battery test. Battery capacity drops
with decreasing ambient temperature.
A well charged battery helps to ensure
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 1/6 in (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. Use of winter tires
is the only way to achieve the maximum ef-
fectiveness of the ABS and the ESP in win-
ter operation.
For safe handling, ensure 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 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 under
1/6in
(4 mm) must be replaced. They are no long-
er suitable for winter operation.
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.