2008 MERCEDES-BENZ G-CLASS SUV engine

Engine compartment
157
If only summer diesel fuel or less cold-resist-
ant winter diesel fuel (e.g. in Mediterranean
regions) is available, you should add an
amount of flow improver to the fuel corre-
sponding to the outside temperature.
Mix the additive with the diesel in good time,
before the flow properties of the diesel
become insufficient. Otherwise, malfunctions
can only be rectified by heating the entire fuel
system, e.g. by parking the vehicle in a heated
garage. G
Risk of fire
Do not use petrol to refuel vehicles with a
diesel engine. Never mix diesel with petrol.
This would damage the fuel system and
engine and could result in a vehicle fire.
Flow improver
The effectiveness of a flow improver is not
guaranteed with every fuel. Observe the infor-
mation provided by the manufacturer when
using a flow improver. Only use flow improv-
ers that have been tested and approved by
Mercedes-Benz. Information about flow
improvers that have been tested and
approved by Mercedes-Benz can be obtained
from any Mercedes-Benz Service Centre. Engine compartment
Bonnet
G
Risk of accident
Do not pull the release lever while the vehi-
cle is in motion. The bonnet may otherwise
open 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 Man-
ual 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 turning area of the fan. You can
otherwise be injured. Vehicles with a petrol engine:
The electronic ignition system uses high
voltage. For this reason, you must never
touch components of the ignition system
(ignition coil, ignition cable, spark plug con-
nector or test socket) when:
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
Vehicles with a diesel engine:
The electronic injection control uses high
voltage. Therefore, never touch fuel injec-
tion system components when:
R the engine is running
R the engine is being started
R the ignition is switched on
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 rods. Operation
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Engine compartment
158 Make sure that the windscreen wipers are
switched off and that the key has been
pulled out of the ignition lock before open-
ing the bonnet.
The bonnet release lever is located in the
driver's footwell. 1
Bonnet release lever
X Pull release lever 1.
The bonnet is released.
! Make sure that the windscreen wipers
are not folded out from the windscreen.
You could otherwise damage the wind-
screen wipers or the bonnet. G 320 CDI
2
Bonnet catch handle
X Lift the bonnet slightly.
X Pull bonnet catch handle 2in the direction
of the arrow and lift the bonnet. G 500, G 55 AMG
3
Bonnet catch handle X
Lift the bonnet slightly.
X Push bonnet catch handle 3in the direc-
tion of the arrow and lift the bonnet.
Closing G
Risk of injury
Make sure that nobody can become trap-
ped 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.
i If the bonnet can be raised slightly, it is
not properly engaged. Open it again and
close it with a little more force. Operation
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Engine compartment
159Engine oil
Depending on driving style, the vehicle con-
sumes a maximum of 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. You can only
estimate the oil consumption after you have
driven a considerable distance.
You will find further information about engine
oil in the "Technical data" section
(Y page 279).
Checking the engine oil level To do so:
R
the vehicle should be parked on level
ground.
R the engine should be switched off for at
least five minutes if the engine was at nor-
mal operating temperature.
R the engine should be switched off for at
least 30 minutes if the engine was not at
operating temperature (i.e. if you only star-
ted the engine briefly). Via the on-board computer
i
Only possible on the G 55 AMG. On all
other models, a dipstick is used to check
the engine oil level (Y page 160).
X Make sure that the key is in position 2in
the ignition lock (Y page 59).
X Press konce on the multi-function
steering wheel. The measurement takes a few seconds. You
will see one of the following messages in the
display:
R
Engine oil level OK
R Add 1.0 litre to reach maximum oil
level R
Add 1.5 litres to reach maximum oil
level
R Add 2.0 litres to reach maximum oil
level
X Top up the oil if necessary ( Ypage 160).
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: Eng. 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 Switch ignition on to check
engine oil level message appears:
X Turn the key to position 2in the ignition
lock (Y page 59).
You will see the following message if you did
not observe the required waiting time:
Observe waiting period Operation
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Engine compartment
160
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).
If the engine is running, the Engine oil
level Not when engine on message
appears.
X Switch off the engine and wait for five
minutes if the engine is at normal operating
temperature, or for about 30 minutes if the
engine is not at normal operating temper-
ature (if the engine was only started
briefly), before measuring.
i If you wish to cancel the measurement,
press the korj button on the multi-
function steering wheel.
Using the oil dipstick
i Only possible on the G 320 CDI and
G 500. On the G 55 AMG, the oil level is
checked using the on-board computer
(Y page 159). Example: G 320 CDI
1
Oil dipstick
2 Maximum mark
3 Minimum mark
X Pull oil dipstick 1out of the oil dipstick
tube.
X Wipe off oil dipstick 1.
X Insert oil dipstick 1into the oil dipstick
tube to the stop, and take it out again.
The oil level is correct if the level is between
minimum mark 3and maximum mark
2.
X Top up the oil if necessary.
i The difference in quantity between mini-
mum mark 3and maximum mark 2is
approximately 2 litres. Topping up the engine oil
G 500
1
Cap G 55 AMG
1
Cap Operation
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Engine compartment
161G 320 CDI
1
Cap
X Unscrew cap 1and remove it.
X Top up with the amount of oil required.
! 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 Screw cap 1onto the filler neck. 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 oth-
erwise be damaging the environment. Oil level in the automatic transmis-
sion
There is no need for you to check the oil level
in the automatic transmission. In the event of
oil loss or problems with gearshifts, have the
automatic transmission checked at a quali-
fied specialist workshop, e.g. at a Mercedes-
Benz Service Centre. Coolant
G
Risk of injury
The cooling system is pressurised. There-
fore, only unscrew the cap once the engine
has cooled down. This means the coolant
temperature gauge must display less than
70 °C. You could otherwise be scalded by
escaping hot coolant.
Coolant consists of water and antifreeze/cor-
rosion inhibitor. Only check the coolant level
when the vehicle is on a level surface and the
engine has cooled down. Checking the coolant level The expansion tank is located in the engine
compartment on the right-hand side of the
vehicle when viewed in the direction of travel.
1
Cap
X Slowly turn cap 1by half a turn in the
direction of the arrow to release excess
pressure.
X Unscrew cap 1completely and remove it.
X Turn cap 2further anti-clockwise and
remove it.
There is sufficient coolant in the expansion
tank if the coolant is level with the mark in
the expansion tank when the coolant is cold
or approximately 1.5 cm higher when hot. Operation
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Tyres and wheels
162
X
Top up the coolant if necessary.
X Replace cap 1and tighten all the way to
the stop.
You will find further information about coolant
in the "Technical data" section
(Y page 280). Windscreen washer system/head-
lamp cleaning system
The washer fluid reservoir is located in the
engine compartment on the right when
viewed in the direction of travel. The head-
lamp cleaning system is also supplied from
the washer fluid reservoir. 1
Cap
X Add windscreen washer concentrate to the
washer fluid all year round. G
Risk of fire
Windscreen washer concentrate is highly
flammable. Fire, naked flames and smoking
are prohibited when windscreen washer
concentrate is being handled.
Use
R a windscreen washer fluid additive
such as MB Summerwash to prevent
smearing (for temperatures above freez-
ing).
R a windscreen washer fluid additive with
antifreeze properties such as MB Winter-
wash (if there is a risk of frost).
X Mix the windscreen washer fluid in a con-
tainer beforehand. Adapt the mixing ratio
to the outside temperatures.
! Only use windscreen washer fluid which
is suitable for plastic lamp lenses. Unsuit-
able windscreen washer fluid could dam-
age the plastic lamp lenses of the head-
lamps.
X To open: pull cap1upwards by the tab.
X To close: press cap 1onto the filler neck
until it clicks into place. Tyres and wheels
Points to remember
! For safety reasons, Mercedes-Benz rec-
ommends that you only use tyres and
wheels which have been approved by
Mercedes-Benz specifically for your vehi-
cle. These tyres have been specially adap-
ted for use with the control systems, such
as ABS or ESP ®
, and are marked as follows:
R MO = Mercedes-Benz Original
If you use other tyres and wheels,
Mercedes-Benz cannot accept any respon-
sibility for damage that may result. Further
information about tyres, wheels and
approved combinations can be obtained
from any Mercedes-Benz Service Centre.
If you use tyres other than those tested and
recommended for Mercedes-Benz vehi-
cles, characteristics such as handling, vehi-
cle noise emissions and fuel consumption
may be adversely affected. In addition, the
wheels may come into contact with the
body or axle components when heavily loa-
ded or when driving with snow chains. This
could result in damage to the tyres or the
vehicle. Operation
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Driving
tips 169Snow chains
For safety reasons, Mercedes-Benz recom-
mends that you only use snow chains which
have been specially approved for your vehicle
by Mercedes-Benz, or are of a corresponding
standard of quality.
! Information about the use of snow chain-
compatible AMG winter tyres is applicable
for AMG tyres. Use of snow chains is only
permissible with these tyres.
If you intend to fit snow chains, please bear
the following points in mind:
R snow chains cannot be fitted to all wheel/
tyre combinations.
R fit the snow chains for maximum tractive
power and driving stability on all four
wheels. Comply with the manufacturer's
installation instructions.
Do not exceed the maximum permissible
speed of 50 km/h.
i You may wish to deactivate ESP ®
when
pulling away with snow chains fitted.
(Y page 49)This way you can allow the
wheels to spin in a controlled manner, ach-
ieving an increased driving force (cutting
action). Winter driving
G
Risk of accident
Do not shift down for additional engine
braking on a slippery road surface. This
could cause the drive wheels to lose their
grip and the vehicle could skid.
You should drive particularly carefully on slip-
pery road surfaces. Avoid sudden accelera-
tion, steering and braking manoeuvres.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:
X Shift the selector lever to N.
X Try to bring the vehicle under control by
using corrective steering. Driving tips
Pulling away on slippery surfaces
! If possible, do not let the drive wheels
spin. Otherwise, you could damage the
drive train.
X When necessary, engage the differential
locks (Y page 94). Rolling with the engine switched off
G
Risk of accident
Never switch the engine off while the vehi-
cle is in motion.
There is no power assistance for the steer-
ing and the service brake when the engine
is not running.
You will require considerably more effort to
steer and brake and, therefore, you could
lose control of the vehicle and cause an
accident. Operation
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Driving
tips 170 Braking
G
Risk of accident
Do not change down for additional engine
braking on a slippery road surface. This
could cause the drive wheels to lose their
grip and the vehicle could skid. G
Risk of accident
Make sure that other road users are not
endangered by your braking.
Downhill gradients On long and steep downhill gradients, espe-
cially if the vehicle is laden or towing a trailer,
you must select shift range 1,2or 3in good
time.
i This also applies if you have activated
cruise control or Speedtronic.
This will use the braking effect of the engine,
so less braking will be required to maintain
the speed. This relieves the load on the brake
system and prevents the brakes from over-
heating and wearing too quickly. If you need
additional braking, depress the brake pedal
repeatedly rather than continuously. Heavy and light loads If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately, but
drive on for a short while. This allows the air-
flow to cool the brakes more quickly.
G
Risk of accident
Never depress the brake pedal continu-
ously while the vehicle is in motion, e.g.
never cause the brakes to rub by applying
constant slight pedal pressure. This causes
the brake system to overheat, increases
the braking distance and can lead to the
brakes failing completely.
If the brakes have been used only moderately,
you should occasionally test their effective-
ness. To do this, brake more firmly from a
higher speed. This improves the grip of the
brakes.
Wet roads If driving in heavy rain for a prolonged period
of time without braking, there may be a
delayed reaction from the brakes when brak-
ing for the first time. You must brake harder.
Therefore, you must maintain a greater dis-
tance from the vehicle in front.Brake firmly after driving on a wet road. This
way the brake discs will become warm, drying
more quickly, which will protect them against
corrosion.
Limited braking performance on salted
roads G
Risk of accident
The layer of salt on the brake discs and the
brake pads/linings may cause a delay in
the braking effect, resulting in a signifi-
cantly longer braking distance, which could
lead to an accident.
To avoid this danger, you should:
R occasionally brake carefully, without put-
ting other road users at risk, when you
are driving on salted roads. This helps to
remove any salt that may have started to
build up on the brake discs and the brake
pads/linings.
R maintain a greater distance to the vehicle
ahead and drive with particular care.
R carefully apply the brakes at the end of a
trip and immediately after commencing a
new trip, so that salt residues are
removed from the brake disc. Operation
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