292 OperationDriving instructionsBrakesTo help prevent brake disk corrosion after
driving on wet road surfaces (particularly
salted roads), it is advisable to brake the
vehicle with considerable force prior to
parking. The heat generated serves to dry
the brakes.
If your brake system is normally only sub-
ject to moderate loads, you should occa-
sionally test the effectiveness of the
brakes by applying above-normal braking
pressure at higher speeds. This will also
enhance the grip of the brake pads.If the parking brake is released and the
brake warning lamp in the instrument clus-
ter stays on, the brake fluid level in the res-
ervoir is too low.
Brake pad wear or a leak in the system may
be the reason for low brake fluid in the res-
ervoir.
Have the brake system inspected immedi-
ately. Contact an authorized
Mercedes-Benz Center.
All checks and service work on the brake
system should be carried out by qualified
technicians only. Contact an authorized
Mercedes-Benz Center.
Only install brake pads and brake fluid rec-
ommended by Mercedes-Benz.Warning!
G
After driving in heavy rain for some time
without applying the brakes or through wa-
ter deep enough to wet brake components,
the first braking action may be somewhat
reduced and increased pedal pressure may
be necessary to obtain expected braking ef-
fect. Maintain a safe distance from vehicles
in front.
Resting your foot on the brake pedal will
cause excessive and premature wear of the
brake pads.
It can also result in the brakes overheating,
thereby significantly reducing their effec-
tiveness. It may not be possible to stop the
vehicle in sufficient time to avoid an acci-
dent.
!Be very careful not to endanger other
road users when you apply the brakes.
Refer to the description of the Brake
Assist System (BAS) (
page 85).
293 Operation
Driving instructions
After hard braking, it is advisable to drive
on for some time, rather than immediately
parking, so that the air stream can cool
down the brakes faster.High-performance brake system
(CLK 55 AMG only)
The high-performance brake system is de-
signed to operate under the extremely high
operating demands required to accommo-
date the performance capabilities of the
vehicle. The brakes may produce a squeak-
ing-type noise depending on the
vehicle speed
brake force applied
ambient conditions, e.g. temperature
and humidity
As with any brake system, the wear of indi-
vidual brake system components such as
brake pads or discs strongly depends on
your driving style and the conditions under
which you operate the vehicle. Thus, a driv-
ing style calling for high demand braking
will cause your vehicle’s brakes to wear
more quickly.
Warning!
G
If other than recommended brake pads are
installed, or other than recommended brake
fluid is used, the braking properties of the
vehicle can be degraded to an extent that
safe braking is substantially impaired. This
could result in an accident.!When driving down long and steep
grades, relieve the load on the brakes
by shifting into a lower gear to use the
engine’s braking power. This helps pre-
vent overheating of the brakes and re-
duces brake pad wear.
Warning!
G
New vehicle brake pads and discs, and re-
placement brake pads and discs may take
several hundred miles of driving until they
provide optimum braking efficiency. Until
that time, you may need to use increased
brake pedal pressure while braking. Please
be aware of this and adjust your driving and
braking accordingly during this break-in
period.
Excessive high demand braking will cause
correspondingly high brake wear. Please be
attentive to the brake warning lamp in the
instrument cluster and brake condition mes-
sages in the multifunction display. Especial-
ly for high performance driving, it is
important to maintain the brake system and
have it checked regularly.
294 OperationDriving instructionsDriving off
Apply the brakes to test them briefly after
driving off. Perform this procedure only
when the road is clear of other traffic.
Warm up the engine gradually. Do not
place full load on the engine until the oper-
ating temperature has been reached.
When starting off on a slippery surface, do
not allow a drive wheel to spin for an
extended period with the ESP switched off.
Doing so may cause serious damage to the
drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
Parking
!Simultaneously depressing the acceler-
ator pedal and applying the brake re-
duces engine performance and causes
premature brake wear and drivetrain
wear.
!Set the parking brake whenever park-
ing or leaving the vehicle. In addition,
move gear selector lever to positionP.
When parking on hills, turn front wheels
towards the road curb.Warning!
G
Do not park this vehicle in areas where com-
bustible materials such as grass, hay or
leaves can come into contact with the hot
exhaust system, as these materials could be
ignited and cause a vehicle fire.
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 in the starter switch
to position
0 and remove the SmartKey
from the starter switch, or press
KEYLESS-GO* start/stop button
(vehicles with KEYLESS-GO*).
Take the SmartKey or the SmartKey with
KEYLESS-GO* with you and lock vehicle
when leaving.
295 Operation
Driving instructions
TiresTreadwear 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 treadwear indicator appears as a solid
band across the tread.Specified tire inflation pressures must be
maintained. This applies particularly if the
tires are subject to extreme operating con-
ditions (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.
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
vehicle safety laws consider a tire to be
worn when the treadwear indicators (TWI)
become 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.
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.
313 Operation
Tires and wheels
Tires and wheels
See an authorized Mercedes-Benz Center
for information on tested and
recommended rims and tires for summer
and winter operation. They can also offer
advice 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. The operating safety of the
vehicle cannot be assured when such tires
are used.
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 bent rims can
cause tire inflation pressure loss and
damage to the tire beads.
If vehicle is heavily loaded, check tire
inflation 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).
Warning!
G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. See an authorized
Mercedes-Benz Center for further informa-
tion. If incorrectly sized rims and tires are
mounted:
The wheel brakes or suspension
components can be damaged.
The operating clearance of the wheels
and the tires may no longer be correct.
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
result in the bolts loosening and possibly an
accident.
335 Operation
Tires and wheels
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.
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, radio, and heater, to the extent that
these items are available as
factory-installed equipment (whether
installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire.
Air pressure is expressed in pounds per
square inch (psi), or kilopascal (kPa) or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.
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 is specific to each vehicle
and may vary from data shown in above
illustration.
337 Operation
Tires and wheels
Maximum load rating
The maximum load in kilograms and
pounds that can be carried by the tire.
Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
vehicle capacity weight and production
options weight.
Maximum tire inflation pressure
This number is the greatest amount of air
pressure that should ever be put in the tire
under normal driving conditions.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by
68 kilograms (150 lbs).
Occupant distribution
The distribution of occupants in a vehicle
at their designated seating positions.Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.
PSI (P
ounds per s
quare i
nch)
A standard unit of measure for air pressure
-> bar, kilopascal (kPa).Recommended tire inflation pressure
Recommended tire inflation pressure
listed on placard located on driver’s door
B-pillar for normal driving conditions.
Provides best handling, tread life and
riding comfort.
Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
Sidewall
The portion of a tire between the tread and
the bead.
396 Practical hintsWhere will I find...?In the case of a flat tire, you may
temporarily use the Minispare wheel when
observing the following restrictions:
Do not exceed a vehicle speed of
50 mph (80 km/h).
Drive to the nearest tire repair facility
to have the flat tire repaired or
replaced as appropriate.
Do not operate vehicle with more than
one Minispare wheel mounted.
More information can be found in the
“Technical data” section (
page 445).Minispare wheel bolts
1Wheel bolt for light alloy rims
2Wheel bolt for Minispare wheel or other
steel rims (located in trunk with spare
wheel)
!Wheel bolts2 must be used when
mounting the Minispare wheel. The use
of any wheel bolts other than wheel
bolts2 for the Minispare will physical-
ly damage the vehicle's brakes.
Warning!
G
Make sure to use the original length wheel
bolts when remounting the original wheel
after it has been repaired.