Page 305 of 506

304 OperationAt the gas stationCheck regularly and before a long trip
1Coolant level
2Brake fluid (fuse box cover removed)
3Windshield washer and headlamp
cleaning system*
Coolant
For normal replenishing, use water (pota-
ble water quality). For more information,
see “Coolant” (
page 310) and see “Fu-
els, coolants, lubricants, etc.”
(
page 453).Brake fluid
Removing fuse box cover (
page 437).
Windshield washer and headlamp
cleaning system*
For more information on filling up the
washer reservoir, see “Windshield washer
system and headlamp cleaning system*”
(
page 312).Engine oil level
For more information on engine oil, see
“Engine oil” (
page 306).
Vehicle lighting
Check function and cleanliness. For more
information on replacing light bulbs, see
“Replacing bulbs” (
page 414).
For more information, see “Exterior lamp
switch” (
page 50).
Tire inflation pressure
For more information, see “Recommended
tire inflation pressure” (
page 322).
iOpening the hood, see (
page 305).
!If you find that the brake fluid in the
brake fluid reservoir has fallen to the
minimum mark or below, have the
brake system checked for brake pad
thickness and leaks immediately.
Notify an authorized Mercedes-Benz
Center immediately. Do not add brake
fluid as this will not solve the problem.
For more information, see also “Practi-
cal hints” (
page 355).
Page 316 of 506

315 Operation
Tires and wheels
Tread depth
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).
Treadwear indicators (TWI) are required by
law. These indicators are located in six
places on the tread circumference and
become visible at a tread depth of approx-
imately
1/16
in (1.6 mm), at which point
the tire is considered worn and should be
replaced.
Recommended minimum tire tread depth:
Summer tires
1/8in (3 mm)
Winter tires
1/6in (4 mm)
1TWI (T
read W
ear I
ndicator)
The treadwear indicator appears as a solid
band across the tread.Storing tires
Cleaning tires
Warning!
G
Although the applicable federal motor safety
laws consider a tire to be worn when the
treadwear indicators (TWI) become visible at
approximately
1/16in (1.6 mm), we recom-
mend that you do not allow 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 re-
duced.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
!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.!Never use a round nozzle to power
wash tires. The intense jet of water can
result in damage to the tire.
Always replace a damaged tire.
Page 328 of 506

327 Operation
Tires and wheels
General:
Depending on the design standards used,
the tire size molded into the sidewall may
have no letter or a letter preceding the tire
size designation.
No letter preceding the size designation
(as illustrated above): Passenger car tire
based on European design standards.
Letter “P” preceding the size designation:
Passenger car tire based on U.S. design
standards.
Letter “LT” preceding the size designation:
Light Truck tire based on U.S. design
standards.
Letter “T” preceding the size designation:
Temporary spare tires which are high
pressure compact spares designed for
temporary emergency use only. Tire width
The tire width1 (
page 326) indicates
the nominal tire width in mm.
Aspect ratio
The aspect ratio2 (page 326) is the
dimensional relationship between tire
section height and section width and is
expressed in percentage. The aspect ratio
is arrived at by dividing section height by
section width. Tire code
The tire code3 (
page 326) indicates
the tire construction type. The “R” stands
for radial tire type. Letter “D” means diag-
onal or bias ply construction; letter “B”
means belted-bias ply construction.
At the tire manufacturer’s option, any tire
with a speed capability above 149 mph
(240 km/h) can include a “ZR” in the size
designation (for example: 245/40 ZR 18).
For additional information, see “Tire speed
rating” (
page 328).
Rim diameter
The rim diameter4 (
page 326) is the
diameter of the bead seat, not the
diameter of the rim edge. Rim diameter is
indicated in inches (in).
Page 331 of 506

330 OperationTires and wheelsLoad identification
1Load identificationIn addition to tire load rating, special load
information may be molded into the tire
sidewall following the letter designating
the tire speed rating1 (
page 330).
No specification given: absence of any text
(like in above example) indicates a
standard load (SL) tire.
XL or Extra Load: designates an extra load
(or reinforced) tire.
Light Load: designates a light load tire.
C, D, E: designates load range associated
with the maximum load a tire can carry at
a specified pressure.
DOT, Tire Identification Number (TIN)
U.S. tire regulations require each new tire
manufacturer or tire retreader to mold a
TIN into or onto a sidewall of each tire
produced.
The TIN is a unique identifier which facili-
tates efforts by tire manufactures to notify
purchasers in recall situations or other
safety matters concerning tires and gives
purchasers the means to easily identify
such tires.
The TIN is comprised of “Manufacturer’s
identification mark”, “Tire size”, “Tire type
code” and “Date of manufacture”.
iFor illustration purposes only. Actual
data on tires is specific to each vehicle
and may vary from data shown in above
illustration.
Page 348 of 506

347 Operation
Vehicle care
Engine cleaning
Prior to cleaning the engine compartment,
make sure to protect electrical compo-
nents and connectors from the intrusion of
water and cleaning agents.
Corrosion protection, such as MB Anticor-
rosion Wax, should be applied to the
engine compartment after every engine
cleaning. Before applying, all control
linkage bushings and joints should be
lubricated. The poly-V-belt and all pulleys
should be protected from any wax.
Vehicle washing
Do not use hot water or wash your vehicle
in direct sunlight. Only use a mild car wash
detergent, such as Mercedes-Benz
approved Car Shampoo.
Thoroughly spray the vehicle with a dif-
fused jet of water. Direct only a very weak
spray towards the ventilation intake. Use
plenty of water and rinse the sponge and
chamois frequently. Rinse with clear water and thoroughly dry
with a chamois. Do not allow cleaning
agents to dry on the finish.
Due to the width of the vehicle, fold in
exterior rear view mirrors prior to running
the vehicle through an automatic car wash
to prevent damage to the mirrors.
In the winter, thoroughly remove all traces
of road salt as soon as possible.
When washing the underbody, do not
forget to clean the inner sides of the
wheels.Soft top
Clean soft top with soft top raised and
locked. Lower the soft top into the storage
compartment only if the soft top is com-
pletely dry. If the soft top is kept in the
storage compartment for a lengthy period,
raise it and air out with the windows open
about every 4 months.
Light colored soft tops should be cleaned
frequently to prevent spots and dirt from
setting in, which could stain and discolor
the soft top material permanently.
iVehicles with KEYLESS-GO*:
If a door handle is hit by a strong jet of
water, and a SmartKey with
KEYLESS-GO* is in close proximity, i.e.
within approximately 3 ft
(approximately 1 m), the vehicle could
be inadvertently locked or unlocked.
!Remove bird droppings immediately.
The organic acid damages the material
and causes the soft top to leak
Never use a power washer to clean the
soft top, as you may damage the soft
top material.
Do not use sharp-edged instruments
for the removal of ice and snow.
Page 351 of 506

350 OperationVehicle careWindow cleaning
Fold wiper arm forward until it snapes
into place.
Use a window cleaning solution on all
glass surfaces.
An automotive glass cleaner is
recommended.Light alloy wheels
Mercedes-Benz approved Wheel Care
should be used for regular cleaning of the
light alloy wheels.
If possible, clean wheels once a week with
Mercedes-Benz approved Wheel Care, us-
ing a soft bristle brush and a strong spray
of water.
Follow instructions on container.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 status 0) before cleaning the windshield. Other-
wise, the wiper motor could suddenly turn
on and cause injury.
!Fold the windshield wiper arms back
onto the windshield before turning the
SmartKey in the starter switch.
Hold onto the wiper when folding the
wiper arm back. If released, the force
of the impact from the tensioning
spring could crack the windshield.
iOnly use acid-free cleaning materials.
Acid may cause corrosion or damage
the clear coat.
Page 352 of 506

351 Operation
Vehicle care
Instrument cluster
Use a gentle dishwashing detergent or
mild detergent for delicate fabrics as a
washing solution. Wipe with a cloth moist-
ened in lukewarm solution. Do not use
scouring agents.
Steering wheel and gear selector lever
Wipe with a damp cloth and dry thoroughly
or clean with Mercedes-Benz approved
Leather Care.Cup holder
Use a gentle dishwashing detergent or
mild detergent for delicate fabrics as a
washing solution. Wipe with a cloth moist-
ened in lukewarm solution. Do not use
scouring agents.
Hard plastic trim items
Pour Mercedes-Benz approved Interior
Care onto soft lint-free cloth and apply
with light pressure.
Headliner and rear window shelf
Clean with soft bristle brush, or use a
dry-shampoo cleaner in case of excessive
dirt.Seat belts
The webbing must not be treated with
chemical cleaning agents. Only use clear,
lukewarm water and soap. Do not dry the
webbing at temperatures above 176°F
(80°C) or in direct sunlight.
Warning!
G
Do not bleach or dye seat belts as this may
severely weaken them. In a crash they may
not be able to provide adequate protection.
Page 353 of 506

352 OperationVehicle careUpholstery
Using aftermarket seat covers or wearing
clothing that have the tendency to give off
coloring (e.g. when wet, etc.) may cause
the upholstery to become permanently dis-
colored. By lining the seats with a proper
intermediate cover, contact-discoloration
will be prevented.
Leather upholstery
Wipe leather upholstery with a damp cloth
and dry thoroughly or clean with
Mercedes-Benz approved Leather Care.
Exercise particular care when cleaning per-
forated leather as its underside should not
become wet.Nubuck leather upholstery
(CLK 55 AMG)
The nubuck leather upholstery is treated
with a protective coating. Wipe nubuck
leather upholstery with damp microfiber
cloth to remove dust and other light stains.
Carefully dab nubuck leather upholstery
with a dry microfiber cloth to remove oil
stains.Plastic and rubber parts
Do not use oil or wax on these parts.
Wood trims
Dampen cloth using water and use damp
cloth to clean wood trims in your vehicle.
Do not use solvents like tar remover or
wheel cleaner nor polishes or waxes as
these may be abrasive.
!Do not use Mercedes-Benz approved
Leather Care or any solvents to clean
nubuck leather upholstery.
Avoid hard scrubbing on nubuck leath-
er upholstery.