315 Operation
Driving instructions
Tire speed rating
Regardless of the tire speed rating, local
speed limits should be obeyed. Use
prudent driving speeds appropriate to
prevailing conditions.An electronic speed limiter prevents your
vehicle from exceeding a speed of
CLK 350, CLK 550:
130 mph (210 km/h)
CLK 63 AMG:
155 mph (250 km/h)
CLK 63 AMG with increased top
speed*:
174 mph (280 km/h)
The factory equipped tires on your vehicle
may have a tire speed rating above the
maximum speed permitted by the
electronic speed limiter.
Make sure your tires have the required tire
speed rating as specified for your vehicle in
the “Technical data” section (
page 482),
for example when purchasing new tires.For Information on how to identify the tire
speed rating on a tire’s sidewall, see “Tire
size designation, load and speed rating”
(
page 349).
If you are uncertain about the correct read-
ing of the information given on a tire’s side-
wall, any authorized Mercedes-Benz
Center will be glad to assist you.
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 win-
ter tires, see “Winter tires” (
page 362).
For additional general information on tire speed
markings on tire sidewall, see “Tire speed rating”
(
page 351).
316 Operation
Driving instructions
Winter driving instructions
The most important rule for slippery or icy
roads is to drive sensibly and to avoid
abrupt acceleration, braking and steering
maneuvers. Do not use the cruise control
system under such conditions.
When the vehicle is in danger of skidding,
move gear selector lever to position N. Try
to keep the vehicle under control by cor-
rective steering action.Road salts and chemicals can adversely af-
fect braking efficiency. Increased pedal
force may become necessary to produce
the normal braking effect.
Depressing the brake pedal periodically
when traveling at length on salt-strewn
roads can bring road-salt-impaired braking
efficiency back to normal.
If the vehicle is parked after being driven
on salt-treated roads, the braking efficien-
cy should be tested as soon as possible af-
ter driving is resumed.
For more information, see “Winter driving”
(
page 362).
iFor information on driving with snow chains,
see “Snow chains” (
page 363).
Warning!G
On slippery road surfaces, never downshift
in order to obtain braking action. This could
result in drive wheel slip and reduced vehi-
cle control. Your vehicle’s ABS will not pre-
vent this type of control loss.
Warning!G
Make sure not to endanger any other road
users when carrying out these braking ma-
neuvers.
Warning!G
If the vehicle becomes stuck in snow, make
sure snow is kept clear of the exhaust pipe
and from around the vehicle with the engine
running. Otherwise, deadly carbon monox-
ide (CO) gases may enter vehicle interior re-
sulting in unconsciousness and death.
To assure sufficient fresh air ventilation,
open a window slightly on the side of the ve-
hicle not facing the wind.
Warning!G
The outside temperature indicator is not de-
s i g n e d t o s e r v e a s a n i c e - w a r n i n g d e v i c e a n d
is therefore unsuitable for that purpose. In-
dicated temperatures just above the freez-
ing point do not guarantee that the road
surface is free of ice.
321 Operation
At the gas station
Take off the fuel cap and set it in the di-
rection of arrow 2 in the recess on the
fuel filler flap.
To prevent fuel vapors from escaping
into open air, fully insert the filler noz-
zle unit.
Only fill your tank until the filler nozzle
unit cuts out – do not top off or
overfill.
Replace the fuel cap by turning it
clockwise until it audibly engages.
Close the fuel filler flap.
Warning!G
Overfilling of the fuel tank may create
pressure in the system which could cause a
gas discharge. This could cause the gas to
spray back out when removing the fuel
pump nozzle, which could cause personal
injury.
iMake sure to close the fuel filler flap before
locking your vehicle as the flap locking pin
prevents closing after you have locked the
vehicle.
iOnly use premium unleaded gasoline with a
minimum Posted Octane Rating of 91 (average
of 96 RON / 86 MON).
Information on gasoline quality can normally be
found on the fuel pump. Please contact gas sta-
tion personnel in case labels on the pump cannot
be found.
For more information on gasoline, see “Premium
unleaded gasoline” (
page 492), or the Factory
Approved Service Products pamphlet (USA only),
or contact an authorized Mercedes-Benz Center.
iLeaving the engine running and the fuel cap
open can cause theú malfunction indicator
lamp (USA only) or the± malfunction indica-
tor lamp (Canada only) to illuminate.
More information can be found in the “Practical
hints” section (
page 381).
322 Operation
At the gas station
Check regularly and before a long trip
Engine compartment (CLK 550, example)
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 328) and see “Fu-
els, coolants, lubricants, etc.”
(
page 489).
Brake fluid
Removing fuse box cover,
see (
page 473).Windshield washer and headlamp
cleaning system*
For more information on filling up the
washer reservoir, see “Windshield washer
system and headlamp cleaning system*”
(
page 330).
Engine oil level
For more information on engine oil, see
“Engine oil” (
page 325).
Vehicle lighting
Check function and cleanliness. For more
information on replacing light bulbs, see
“Replacing bulbs” (
page 443).
For more information, see “Exterior lamp
switch” (
page 55).
Tire inflation pressure
For more information, see “Checking tire
inflation pressure” (
page 341).
iOpening the hood, see (page 323).
!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 380).
326 Operation
Engine compartment
CLK 63 AMG
1Oil dipstick
2Upper (max) mark
3Lower (min) markTo check the engine oil level with the oil
dipstick, do the following:
Open the hood (page 323).
Pull out oil dipstick1.
Wipe oil dipstick1 clean.
Fully insert oil dipstick1 into the
dipstick guide tube.
Pull out oil dipstick1 again after
approximately 3 seconds to obtain ac-
curate reading.
The oil level is correct when it is be-
tween the lower (min) mark3 and
upper (max) mark2 of oil dipstick1.
If necessary, add engine oil.
For adding engine oil, see “Adding en-
gine oil” (
page 327).
For more information on engine oil, see
“Fuels, coolants, lubricants, etc.”
(
page 489).
For more information on messages in the
multifunction display concerning engine
oil, see the “Practical hints” section
(
page 409).
iCLK 350:
The filling quantity between the upper and lower
marks on the oil dipstick is approximately
2.1 US qt. (2.0 l).
CLK 550 / CLK 63 AMG:
The filling quantity between the upper and lower
marks on the oil dipstick is approximately
1.6 US qt. (1.5 l).
327 Operation
Engine compartment
Adding engine oil
CLK 350 / CLK 550
1Filler cap
CLK 63 AMG
1Filler cap
Unscrew filler cap1 from filler neck.
Add engine oil as required. Be careful
not to overfill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.
Screw filler cap1 back on filler neck.
More information on engine oil can be
found in the “Technical data” section
(
page 489) and (page 491).
Transmission fluid level
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Center
check the automatic transmission.
!Only use approved engine oils and oil filters
required for vehicles with Maintenance System.
For a listing of approved engine oils and oil fil-
ters, refer to the Factory Approved Service Prod-
ucts pamphlet (USA only) in your vehicle
literature portfolio, or contact an authorized
Mercedes-Benz Center.
Using engine oils and oil filters of specification
other than those expressly required for the
Maintenance System, or changing of oil and oil
filter at change intervals longer than those called
for by the Maintenance System will result in
engine or emission control system damage not
covered by the Mercedes-Benz Limited
Warranty.
!Excess oil must be siphoned or drained off.
It could cause damage to the engine and emis-
sion control system not covered by the
Mercedes-Benz Limited Warranty.
328 Operation
Engine compartment
Coolant
The engine coolant is a mixture of water
and anticorrosion/antifreeze.
When checking the coolant level,
the vehicle must be parked on level
ground
the coolant temperature must be be-
low 158°F (70°C)
The coolant expansion tank is located on
the passenger side of the engine
compartment.
1Coolant expansion tank
2Cap
Using a rag, turn cap 2 slowly
approximately one half turn counter-
clockwise to release any excess
pressure.
Continue turning the cap 2 counter-
clockwise and remove it.
The coolant level is correct if the level
for cold coolant: reaches the marking
(plastic bridge) inside the reservoir
for warm coolant: is approximately
0.6 in (1.5 cm) higher
Add coolant as required.
Replace and tighten cap 2.
More information on coolant can be found
in the “Technical data” section
(
page 494).
Warning!G
In order to avoid potentially serious burns:
Use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system,
or if the coolant temperature indicator
indicates that the coolant is overheated.
Do not remove pressure cap on coolant
reservoir if the coolant temperature is
above 158°F (70°C). Allow the coolant
to cool down before removing cap.
The coolant reservoir contains hot fluid
and is under pressure.
Using a rag, slowly open the cap approx-
imately 1/2 turn to relieve excess pres-
sure. If opened immediately, scalding
hot fluid and steam will be blown out un-
der pressure.
Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene gly-
col which may burn if it comes into con-
tact with hot engine parts.
329 Operation
Engine compartment
Battery
Your vehicle’s battery is located in the
engine compartment on the right-hand
side (
page 464).
The battery should always be sufficiently
charged in order to achieve its rated
service life. Refer to Maintenance Booklet
for battery maintenance intervals.
If you use your vehicle mostly for
short-distance trips, you will need to have
the battery charge checked more
frequently.
When replacing the battery, always use
batteries approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, consult an
authorized Mercedes-Benz Center about
steps you need to observe.Batteries contain materials that can harm
the environment if disposed of improperly.
Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.
Warning!G
Observe all safety instructions and precau-
tions when handling automotive batteries.
Risk of explosion.
Fire, open flames and smoking
are prohibited when handling
batteries. Avoid creating sparks.
Battery acid is caustic. Do not
allow it to come into contact
with skin, eyes or clothing.
Wear suitable protective cloth-
ing, especially gloves, apron and
faceguard.
Wear eye protection.
Rinse any acid spills immediate-
ly with clear water. Contact a
physician if necessary.
Keep children away.
Follow the instructions in this
Operator’s Manual.