Page 244 of 323

Engine compartment
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
Hood
Warning!
To help prevent personal injury, stay clear of
moving parts when the hood is open and the engine
is running. Be sure the hood is properly closed
before driving. When closing hood, use extreme
caution not to catch hands or fingers.The engine is equipped with a transistorized
ignition system. Because of the high voltage it is
dangerous to touch any components (ignition coils,
spark plug sockets, diagnostic socket) of the
ignition system
• with the engine running,
• while starting the engine,
• if ignition is “on” and the engine is turned
manually.If you see flames, steam or smoke coming from the
engine compartment, or if the coolant temperature
gauge indicates that the engine is overheated, do
not open the hood. Move away from vehicle and do
not open the hood until the engine has cooled. If
necessary, call a fire department.To o pen :
To unlock the hood, pull release lever (1) under the
driver’s side of the instrument panel. At the same time a
handle will extend out of the radiator grill (it may be
necessary to lift the hood up slightly).
Caution!
To avoid damage to the windshield wiper or hood, open
the hood only with wiper in the parked position.
P88.40-2025-26
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Page 246 of 323

Engine compartment
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
Checking engine oil level (CLK 320 shown)
1Oil dipstick
2Oil filler cap
To check the engine oil level, park vehicle on level
ground, with engine at normal operational temperature.
Check engine oil level approximately 5 minutes after
stopping the engine, allowing for the oil to return to the
oil pan.Wipe oil dipstick clean prior to checking the engine oil
level. Fully insert dipstick in tube, and remove after
three seconds to obtain accurate reading.
Oil level must be between the
lower (min) and upper (max) mark of
the dipstick.
Fill quantity between upper and lower dipstick marking
level is approximately 2.1 US qt (2.0 l).
Do not overfill the engine.
Excessive oil must be drained
or siphoned. It could cause damage to engine and
catalytic converter not covered by the Mercedes-Benz
Limited Warranty.
See malfunction and warning messages on page222 if
an engine oil level display appears on the multifunction
display when the engine is running.
Note:
See page110for engine oil level indicator.
Mercedes-Benz
Mercedes-Benz
2
1
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Page 248 of 323

Engine compartment
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
Adding coolant
If coolant has to be added, a 50 / 50 mixture of water and
MB anticorrosion / antifreeze should be added.
The drain plugs for the cooling system are located on
the right side of the engine block and at the bottom of
the radiator.
Anticorrosion / antifreeze mixture, see page311.
Warning!
In order to avoid possible serious burns or injury:
• 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 gauge indicates that the coolant is
overheated.• Do not remove pressure cap on coolant
reservoir if engine temperature is above 194°F
(90°C). Allow engine to cool down before
removing cap. The coolant reservoir contains
hot fluid and is under pressure.
• Using a rag, slowly open cap approximately
1/2 turn to relieve excess pressure. If opened
immediately, scalding hot fluid and steam will
be blown out under pressure.• Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which may
burn if it comes into contact with hot engine
parts.
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Page 254 of 323

Tires, Wheels
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
Changing wheelsMove vehicle to a level area which is a safe distance
from the roadway.
1. Set parking brake and turn on hazard warning
flasher.
2. Move selector lever to position “P” and turn off
engine.
3. Prevent vehicle from rolling away by blocking
wheels with wheel chocks (not supplied with
vehicle) or sizable wood block or stone. When
changing a wheel on a hill, place chocks on the
downhill side blocking both wheels of the other
axle. On a level road, place one chock in front of and
one behind the wheel that is diagonally opposite to
the wheel being changed.
Warning!
The jack is designed exclusively for jacking up the
vehicle at the jack tubes built into either side of the
vehicle. To help avoid personal injury, use the jack
only to lift the vehicle during a wheel change.
Never get beneath the vehicle while it is supported
by the jack. Keep hands and feet away from the area
under the lifted vehicle. Always firmly set parking
brake and block wheels before raising vehicle with
jack.Do not disengage parking brake while the vehicle is
raised. Be certain that the jack is always vertical
when in use, especially on hills. Always try to use
the jack on level surface. Be sure that the jack arm
is fully inserted in the jack tube. Always lower the
vehicle onto sufficient capacity jackstands before
working under the vehicle.
Wa r n i n g !
Before working on the vehicle, e.g. when changing
wheels, the roll bar should be raised with the
switch, and the electronic key be removed from the
steering lock, to prevent possible injury.
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Page 258 of 323
Tires, Wheels
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index 11. Lower vehicle. Remove jack and insert jack tube
cover.
12. Using the wrench, tighten the five bolts evenly,
following the sequence illustrated, until all bolts are
tight.
Observe a tightening torque of 80 ft.lb. (110 Nm).
13. Ensure proper tire pressure.
34
2
5
Warning!
Always replace wheel bolts that are damaged or
rusted.Never apply oil or grease to wheel bolts.Damaged wheel hub threads should be repaired
immediately.Incorrect mounting bolts or improperly tightened
mounting bolts can cause the wheel to come off.
This could cause an accident. Be sure to use the
correct mounting bolts.Wa r n i n g !
The spare wheel rim is for temporary use only. Use
for over a total of 12 000 miles (20 000 km)
(aggregate of all uses) may cause wheel rim failure
leading to an accident and possible injuries.
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Page 260 of 323
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
If a tire constantly loses air, it should be inspected for
damage.
The spare tire should be checked periodically for
condition and inflation. Spare tire will age and become
worn over time even if never used, and thus should be
inspected and replaced when necessary.
Warning!
Do not overinflate tires. Overinflating tires can
result in sudden deflation (blowout) because they
are more likely to become punctured or damaged
by road debris, potholes etc.. Follow recommended
inflation pressures.Do not overload the tires by exceeding the specified
vehicle capacity weight (as indicated by the label
on the driver’s door latch post). Overloading the
tires can overheat them, possibly causing a
blowout. Tires, Wheels
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Page 263 of 323

Jump starting
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
Jump starting
If the battery is discharged, the engine should be started
with jumper cables and the (12 V) battery of another
vehicle.
Only use 12 V battery to jump start your vehicle. Jump
starting with more powerful battery could damage the
vehicle’s electrical systems, which will not be covered
by the Mercedes-Benz Limited Warranty.
The battery is located in the trunk under the trunk floor.
Warning!
Failure to follow these directions will cause
damage to the electronic components, and can lead
to a battery explosion and severe injury or death.Never lean over batteries while connecting or jump
starting, you might get injured.Battery fluid contains sulfuric acid. Do not allow
this fluid to come in contact with eyes, skin or
clothing. In case it does, immediately flush affected
area with water, and seek medical help if
necessary.A battery will also produce hydrogen gas, which is
flammable and very explosive. Keep flames or
sparks away from battery, avoid improper
connection of jumper cables, smoking etc..Read all instructions before proceeding.Proceed as follows:
1. Position the vehicle with the charged battery so that
the jumper cables will reach, but never let the
vehicles touch. Make sure the jumper cables do not
have loose or missing insulation.
2. On both vehicles:
•Turn off engine and all lights and accessories,
except hazard warning flashers or work lights.
•Apply parking brake and shift selector lever to
position “P”.
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Page 266 of 323

Towing
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index CLK 430:
Cover removal:
Hold left and right end of grille and pull out.
Cover installation:
Engage left and right end of grille and press in securely.
P88.20-2027-26
We recommend that the vehicle be transported using
flat bed equipment. This method is preferable to other
types of towing.
The vehicle may be towed with all wheels on the ground
and the selector lever in position “N” for distances up to
30 miles (50 km) and at a speed not to exceed 30 mph
(50 km/h). The electronic key must be in steering lock
position 2.
To be certain to avoid a possibility of damage to the
transmission, however, we recommend the drive shaft
be disconnected at the rear axle drive f lange for any
towing beyond a short tow to a nearby garage.
Do not tow with sling-type equipment. Towing with
sling-type equipment over bumpy roads will damage
radiator and supports.
Use wheel lift, dolly, or flat bed equipment, with
electronic key in steering lock turned to position 0.Warning!
With the engine not running, there is no power
assistance for the braking and steering systems. In
this case, it is important to keep in mind that a
considerably higher degree of effort is necessary to
brake and steer the vehicle.
266