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DIN 51628 German standard can lead to
increased wear, engine damage and dam-
age to the exhaust system.
Do not use the following:
R marine diesel
R heating oil
R bio-diesel
R vegetable oil
R petrol
R paraffin
R kerosene
Do not add such fuels to diesel fuel and do
not use any special additives (exception:
flow improvers – see "Low outside temper-
atures").
Damage caused by the use of unapproved
fuels or additives is not covered by the
implied warranty.
Further information on "Fuel" (Y page 287).
Low outside temperatures The flow properties of diesel may be inade-
quate at low ambient temperatures.
Diesel fuel with improved cold flow qualities
is available during the winter months. In
Europe, various climate-dependent low-tem-
perature classes are defined in EN 590. Using
diesel fuels which meet the climatic require-
ments set out in EN 590 can help avoid oper-
ating problems. The flow properties of diesel
fuel may be inadequate at unusually low out-
side temperatures or when using fuel which
has not been adjusted to climatic conditions
(e.g. diesel fuels from Mediterranean
regions).
Flow improver
Flow improvers may be added to improve low-
temperature resistance. The effectiveness of
a flow improver is not guaranteed with every
fuel.
Correct dosage and mixing are decisive fac-
tors in ensuring improvement in low-temper- ature resistance. Under certain circumstan-
ces, an excessive dosage may actually
decrease low-temperature resistance, and
should therefore be avoided (follow the man-
ufacturer's dosing instructions).
Mix the additive with the diesel in good time,
before the flow properties of the diesel
become inadequate. Otherwise, malfunctions
can only be rectified by heating the entire fuel
system, e.g. by parking the vehicle in a heated
garage.
Observe the information provided by the man-
ufacturer when using a flow improver. Only
use flow improvers that have been tested and
approved by Mercedes-Benz. You can obtain
further information from any Mercedes-Benz
Service Centre.
Engine compartment
Bonnet
G
Risk of accident
Do not pull the release lever while the vehicle
is in motion. If you do so, the bonnet may open
up and block your view.
Opening G
Risk of injury
There is a risk of injury if the bonnet is open,
even if the engine is not running.
Some engine components can become very
hot.
To avoid the risk of burns, only touch those
components described in the Owner’s Manual
and observe the relevant safety notes. G
Risk of injury
The radiator fan between the radiator and the
engine can start automatically, even if the key
has been removed from the ignition lock. For
this reason, you must not reach into the fan
rotation area. Otherwise, you could be
injured. 174
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Vehicles with a petrol engine:
The electronic ignition system uses high volt-
age. For this reason, you must never touch
ignition system components (ignition coil,
ignition cable, spark plug connector or test
socket) while:
R the engine is running.
R the engine is being started.
R the ignition is switched on and the engine
is being cranked by hand.
You could otherwise suffer an electric shock
and be seriously or even fatally injured.
Vehicles with a diesel engine:
The electronic injection control uses high volt-
age. For this reason, you must never touch
injection system components while:
R the engine is running.
R the engine is being started.
R the ignition is switched on.
You could otherwise suffer an electric shock
and be seriously or even fatally injured.
X Make sure that the windscreen wipers are
switched off. G
Risk of injury
The windscreen wipers and wiper linkage
could be set in motion.
When the bonnet is open, you or others could
be injured by the wiper linkage.
Make sure that the windscreen wiper is
switched off. Remove the key or make sure
that no ignition level has been selected on
KEYLESS GO *. Inthe instrument cluster, all of
the indicator lamps must be out. The bonnet release lever is located in the
driver's footwell. X
Pull bonnet release lever :.
The bonnet is released.
! Make sure that the windscreen wipers
are not folded away from the windscreen.
Otherwise, you could damage the wind-
screen wipers or the bonnet.
The handle for opening the bonnet is located
above the radiator grille. X
Reach into the gap, pull bonnet catch han-
dle ;up and lift the bonnet.
Closing G
Risk of injury
Make sure that nobody can become trapped
as you close the bonnet.
X Lower the bonnet and let it fall from a
height of approximately 20 cm.
X Check that the bonnet has engaged prop-
erly. Engine compartment
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i
If the bonnet can be raised slightly, it is
not properly engaged. Open it again and
close it with a little more force. Engine oil
Depending on driving style, the vehicle con-
sumes up to 0.8 l oil per 1,000 km. The oil
consumption may be higher than this when
the vehicle is new or if you frequently drive at
high engine speeds.
Checking the engine oil level Before checking the engine oil level the fol-
lowing conditions for the vehicle should be
met:
R the vehicle should be parked on level
ground.
R the engine should be switched off for at
least five minutes if the engine is at normal
operating temperature.
R the engine should be switched off for at
least 30 minutes if the engine is not at
operating temperature (i.e. if you only start
the engine briefly).
Using the on-board computer*
i Only possible on the GL 450 CDI 4MATIC.
On all other models, a dipstick is used to
check the engine oil level (Y page 177).
X Make sure that the key is in position
2(Y page 63) in the ignition lock.
X Press the &or* button to select the
following message: The measurement takes a few seconds. You
will see one of the following messages in the
multi-function display:
R
Engine oil level OK
R Add 1.0 litre to reach max. oil
level
R Add 1.5 litres to reach max. oil
level
R Add 2.0 litres to reach max. oil
level
X Top up the oil if necessary (Y page 177).
Other messages in the multi-function dis-
play
If the engine is at normal operating tempera-
ture and there is too much oil, you will see the
following message:
Engine oil level
Reduce oil level
X Have excess oil siphoned off.
! There is a risk of damage to the engine or
the catalytic converter if there is excess oil
in the engine.
If the Turn on ignition to see engine
oil level message appears:
X Turn the key to position 2(Y page 63) in
the ignition lock.
You will see the following message if you have
not observed the required waiting period:
Observe waiting period
X Repeat the measurement after about five
minutes if the engine is at normal operating
temperature.
X Repeat the measurement after about
30 minutes if the engine is not at normal
operating temperature (if the engine was
only started briefly).
The following message appears if the engine
is running:
Engine oil level Not when engine on
X Switch off the engine and wait for five
minutes if the engine is at normal operating 176
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Page 180 of 309

temperature, or for about 30 minutes if the
engine is not at normal operating temper-
ature (if you had started the engine only
briefly), before measuring.
i If you wish to cancel the measurement,
press the *or& button on the multi-
function steering wheel.
Using the oil dipstick Vehicles with a petrol/diesel engine (example)
X Pull oil dipstick :out of the oil dipstick
tube.
X Wipe off oil dipstick :.
X Insert oil dipstick :into the oil dipstick
tube to the stop, and take it out again.
The oil level is correct if the level is between
the minimum mark =and maximum
mark ;.
X Top up the oil if necessary.
Topping up the engine oil H
Environmental note
When topping up the oil, take care not to spill
any. Oil must not be allowed to escape into
the soil or waterways. You would otherwise be
damaging the environment. Cap (example)
X
Turn cap :anti-clockwise and remove.
X Top up with the amount of oil required
(Y page 289).
i The difference in quantity between the
minimum mark and maximum mark is
approximately 2 litres.
! Do not add too much oil. If too much oil
is added and the oil level is above the max-
imum mark on the dipstick, the engine or
catalytic converter could be damaged.
Have excess oil siphoned off.
X Replace cap :on the filler neck and
tighten clockwise.
Ensure that the cap locks into place
securely.
For further information on engine oil, see
(Y page 289). Coolant
Only check the coolant level when the vehicle
is on a level surface and the engine has cooled
down.
X Turn the key to position 2(Y page 63) in
the ignition lock.
X Check the coolant temperature gauge in
the multi-function display. G
Risk of injury
The cooling system is pressurised. Therefore,
only unscrew the cap once the engine has Engine compartment
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cooled down. The coolant temperature gauge
must display less than 70 †. Otherwise, you
could be scalded if hot coolant escapes.
The coolant expansion tank is located in the
engine compartment on the left when viewed
in the direction of travel. X
Slowly turn cap :half a turn anti-clock-
wise and allow excess pressure to escape.
X Turn cap :further anti-clockwise and
remove it.
There is sufficient coolant in expansion
tank ;if the coolant is level with marker
bar =in the filler neck when cold or
approximately 1.5 cm higher when hot.
X Top up as necessary with coolant which has
been tested and approved by Mercedes-
Benz.
X Replace cap :and tighten all the way to
the stop.
For further information on coolant, see
(Y page 291). Windscreen washer system/head-
lamp cleaning system*
The washer fluid reservoir for the windscreen
washer system and headlamp cleaning sys-
tem* is located in the engine compartment on the left-hand side when viewed in the
direction of travel.
i
Add windscreen washer concentrate to
the washer fluid all year round. G
Risk of fire
Windscreen washer fluid is highly flammable.
Fire, naked flames and smoking are prohibi-
ted when handling washer fluid concentrate.
! Only use washer fluid concentrate which
is suitable for plastic lenses. Unsuitable
washer fluid concentrate could damage the
plastic lenses of the headlamps.
X Mix the windscreen washer fluid in a con-
tainer beforehand.
X At temperatures above freezing:
Fill the washer fluid reservoir with a mix of
water and windscreen washer concentrate
(e.g. MB SummerFit).
X At temperatures below freezing:
Fill the washer fluid reservoir with a mix of
water, antifreeze additive and windscreen
washer concentrate (e.g. MB WinterFit).
Adapt the mixing ratio to the outside tem-
peratures.
X To open: pull cap:upwards by the tab.
X Top up with the premixed washer fluid.
X To close: press cap :onto the filler neck
until it engages. 178
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Page 182 of 309

Tyres and wheels
Points to remember
! For safety reasons, Mercedes-Benz rec-
ommends that you only use tyres, wheels
and accessories which have been approved
by Mercedes-Benz specifically for your
vehicle. These tyres have been specially
adapted for use with the control systems,
such as ABS or ESP ®
, and are marked as
follows:
R MO = Mercedes-Benz Original
R MOE = Mercedes-Benz Original Exten-
ded* (tyres with run-flat characteristics)
Only use Mercedes-Benz Original Extended
tyres* on wheels that have been specifi-
cally approved by Mercedes-Benz.
If you use other tyres, wheels and acces-
sories, Mercedes-Benz cannot accept any
responsibility for damage that may result
from this. Further information about tyres,
wheels and approved combinations can be
obtained from any Mercedes-Benz Service
Centre.
! If you fit tyres other than those tested and
recommended by Mercedes-Benz, charac-
teristics such as handling, noise levels and
fuel consumption, etc. may be adversely
affected. In addition, when driving with a
load, tyre dimensional variations could
cause the tyres to come into contact with
the bodywork and axle components. This
could result in damage to the tyres or the
vehicle.
! Retreaded tyres are neither tested nor
recommended by Mercedes-Benz, since
previous damage cannot always be detec-
ted on retreaded tyres. As a result,
Mercedes-Benz cannot guarantee vehicle
safety if retreaded tyres are fitted. Do not
fit used tyres if you have no information
about their previous usage. G
Risk of accident
Tyres, wheels or accessories which have not
been approved by Mercedes-Benz for your
vehicle or are not used as they should be, can
impair driving safety. As a result, you could
cause an accident. Before purchasing and
using them, enquire about their suitability,
legal stipulations and factory recommenda-
tions at a Mercedes-Benz Service Centre.
Modification work on the brake system and
wheels is not permitted, nor is the use of
spacer plates or brake dust shields. This inva-
lidates the General Operating Permit for the
vehicle.
Notes on selecting, fitting and replac-
ing tyres R
Only fit tyres and wheels of the same type
and make.
R Only fit tyres of the correct size onto the
wheels.
R After fitting new tyres, run them in at mod-
erate speeds for the first 100 km as they
only reach their full performance after this
distance.
R Fit new tyres on the front wheels first if
tyres of the same size are required on the
front and rear wheels.
R Replace the tyres after six years at the lat-
est, regardless of wear. This also applies to
the spare wheel*.
R Do not drive with tyres which have too little
tread depth, as this significantly reduces
the traction on wet roads (aquaplaning).
! Store tyres that are not being used in a
cool, dry and preferably dark place. Protect
the tyres against oil, grease, petrol and die-
sel.
Notes on regularly inspecting wheels
and tyres R
Regularly check the wheels and tyres of
your vehicle for damage (e.g. cuts, punctu- Tyres and
wheels
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res, tears, bulges on tyres and deformation,
cracks or severe corrosion on wheels), at
least every 14 days, as well as after driving
off-road or on rough roads. Damaged
wheels can cause a loss of tyre pressure.
R Regularly check the tyre tread depth and
the condition of the tread across the whole
width of the tyre (Y page 180). If neces-
sary, turn the front wheels to full lock in
order to inspect the inner side of the tyre
surface.
R All wheels must have a valve cap to protect
the valve against dirt and moisture. Do not
fit anything onto the valve (such as tyre
pressure monitoring systems) other than
the standard valve cap or other valve caps
approved by Mercedes-Benz for your vehi-
cle.
R Regularly check the pressure of all the tyres
including the spare tyre*, particularly prior
to long trips, and correct the pressure as
necessary (Y page 180).
Notes on driving R
While driving, pay attention to vibrations,
noises and unusual handling characteris-
tics, e.g. pulling to one side. This may indi-
cate that the wheels or tyres are damaged.
If you suspect that a tyre is defective,
reduce your speed and stop the vehicle as
soon as possible to check the wheels and
tyres for damage. Hidden tyre damage
could also be causing the unusual handling
characteristics. If you find no signs of dam-
age, have the wheels and tyres examined
at a specialist workshop, for example at a
Mercedes-Benz Service Centre.
R When parking your vehicle, make sure that
the tyres do not get deformed by the kerb
or other obstacles. If it is necessary to drive
over kerbs, speed humps or similar eleva-
tions, try to do so slowly and at an obtuse
angle. Otherwise, the tyres, particularly the
sidewalls, can get damaged. Direction of rotation
Tyres with a specified direction of rotation
have additional benefits, e.g. if there is a risk
of aquaplaning. You will only gain these ben-
efits if the correct direction of rotation is
observed.
An arrow on the sidewall of the tyre indicates
its correct direction of rotation.
i You may fit a spare tyre* against the
direction of rotation. Tyre tread
G
Risk of accident
Bear in mind that:
R tyre grip decreases rapidly on wet roads
when the tread depth is less than 3 mm.
Thus, you should replace tyres that have
insufficient tread.
R winter tyres should be replaced when the
tread depth is 4 mm or less as they will no
longer provide adequate grip.
R the tread on a tyre may not wear evenly.
Thus, you should regularly check the tread
depth and the condition of the tread across
the entire width of all tyres. If necessary,
turn the front wheels to full lock in order to
inspect the tyre tread more easily.
Otherwise, you could lose control of the vehi-
cle and cause an accident due to the reduced
grip of the tyres on the road. Tyre pressures
i You will find a table of tyre pressures for
various operating conditions on the inside
of your vehicle's fuel filler flap.
The applicable value for the spare
wheel*/"Minispare" emergency spare
wheel* is stated on the spare wheel and in
the technical data section.
Unless otherwise specified, the tyre pres-
sures on the inside of the fuel filler flap are 180
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valid for all factory-supplied tyres approved
for the vehicle.
If a tyre size precedes a tyre pressure, the tyre
pressure information following is only valid
for that tyre size.
Instead of the complete tyre size, the rim
diameter alone, for example
R 16or16" may
be listed. Rim diameter
:is part of the tyre size and
can be found on the tyre sidewall. G
Risk of accident
Tyre pressure that is either too high or too low
has a negative effect on the vehicle’s driving
safety, which could lead you to cause an acci-
dent. Therefore, you should regularly check
the pressure of all the tyres, particularly prior
to long trips, and correct the pressure as nec-
essary.
To test tyre pressure, use a suitable pressure
gauge. The outer appearance of a tyre does
not permit any reliable conclusion about the
tyre pressure. On vehicles fitted with the elec-
tronic tyre pressure monitor*, the tyre pres-
sure can be checked in the on-board com-
puter. G
Risk of accident
Do not fit anything else to the tyre valve other
than the standard valve cap. In particular, ret-
rofitted tyre pressure monitors which are
screwed onto the valve may overload it and
cause it to fail. Due to their design, the valve
is kept open continuously, which may lead to
air loss. G
Risk of accident
Should the tyre pressure drop repeatedly:
R check the tyre for foreign bodies.
R check whether the wheel is losing air or the
valve is leaking.
R make sure that only a valve cap approved
by Mercedes-Benz has been fitted on the
tyre valve.
Tyre pressures that are too low have a nega-
tive effect on vehicle safety, which could lead
you to cause an accident.
If possible, you should only correct tyre pres-
sures when the tyres are cold. Depending on
the ambient temperature, the speed you are
driving at and the load on the tyres, the tyre
temperature and thus the tyre pressure may
change by approximately 0.1 bar per 10 †.
Take this into account when checking the
pressure of warm tyres and only correct it if Tyres and wheels
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