overheating MERCEDES-BENZ G-Class 2012 W463 Owner's Manual

Turn off the engine before refueling.
Whenever you are around gasoline, avoid
inhaling fumes and any skin or clothing
contact.
Direct skin contact with fuels and the
inhalation
of
fuel vapors are damaging to your
health. G
WARNING
Overfilling of the fuel tank may create
pressure in the system which could cause a
gas discharge. This could cause the gasoline
to spray back out when removing the fuel
pump nozzle, which could cause personal
injury.
! Do not

use diesel to refuel vehicles with a
gasoline engine. Even small amounts of the
wrong fuel result in damage to the fuel
system and engine.
! Do not switch on the ignition if you
accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the fuel lines.
Notify a qualified specialist workshop and
have the fuel tank and fuel lines drained
completely. Gasoline
Fuel grade !
You should only refuel with unleaded
premium-grade gasoline as this avoids
damaging the catalytic converter.
If engine running problems are apparent,
have the cause checked immediately and
repaired. Excess unburned fuel can
otherwise enter the catalytic converter,
leading to overheating and possibly
causing a fire.
i Only refuel

with premium-grade unleaded
gasoline with a specified minimum octane
number of 91 (average value of 96 RON/
86 MON).
You will usually find information about the
fuel grade on the pump. If you cannot find the label on the gasoline pump, ask the gas
station staff.
You
can

find more information under "Fuel"
(Y page 273), by contacting an authorized
Mercedes-Benz Service Center or by
visiting http://bevo.mercedes-
benz.com.
! Use a filter when refueling from a fuel can.
Otherwise, the fuel lines and/or injection
system could be blocked by particles from
the fuel can. Refueling
Fuel filler flap When you open or close the vehicle with the
SmartKey, the fuel filler flap is automatically
unlocked or locked.
The position of the fuel filler cap
8
is
displayed in

the instrument cluster. The arrow
next to the filling pump indicates the side of
the vehicle. The fuel filler flap is located to the
rear on the right. Example: G 550 fuel filler cap
:
To open the fuel filler flap
; Tire pressure table
= Fuel type
? To insert the fuel filler cap
Opening X
Switch off the engine. Refueling
125
Driving and parking Z

accelerate. This could lead to accidents and
injury.
Rolling with the engine switched off G
WARNING
There is no power assistance for the steering
and the

brake when the engine is not running.
Steering and braking requires significantly
more effort and you could lose control of the
vehicle and cause an accident as a result.
Do not turn off the engine while the vehicle is
in motion.
Exhaust check G
WARNING
Inhalation
of exhaust gas is hazardous to your
health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause
unconsciousness and possible death.
Do not

run the engine in confined areas (such
as a garage) which are not properly ventilated.
If you think that exhaust gas fumes are
entering the vehicle while driving, have the
cause determined and corrected
immediately. If you must drive under these
conditions, drive only with at least one
window fully open at all times.
Certain engine systems are designed to keep
the level of poisonous components in exhaust
fumes within legal limits.
These systems only work at peak efficiency
when they are maintained exactly in
accordance with the manufacturer's
specifications. For this reason, all work on the
engine must be carried out only by qualified
and authorized Mercedes-Benz technicians.
The engine settings must not be changed in
any circumstances. Furthermore, all specific
service work must be carried out at regular
intervals and in accordance with the
Mercedes-Benz service requirements. Details
can be found in the Maintenance Booklet. Brakes
Important safety notes G
WARNING
On
slippery road surfaces, never downshift in
order to obtain braking action. This could
result in

drive wheel slip and reduced vehicle
control. Your vehicle's ABS will not prevent
this type of control loss.
Do not engage the transfer case in position
LOW when driving on ice or packed snow. At
speeds below 18 mph (30 km/h) vehicle
steering is adversely affected by the Off-road
ABS.
Downhill gradients !
On long and steep gradients, you must
reduce the load on the brakes by shifting
early to

a lower gear. This allows you to take
advantage of the engine braking effect and
helps avoid overheating and excessive
wear of the brakes.
When you take advantage of the engine
braking effect, a drive wheel may not turn
for some time, e.g. on a slippery road
surface. This could cause damage to the
drive train. This type of damage is not
covered by the Mercedes-Benz warranty.
Heavy and light loads G
WARNING
Depressing
the brake pedal constantly results
in excessive

and premature wear to the brake
pads.
It may also cause the brakes to overheat,
seriously impairing their effectiveness. It may
then not be possible to stop the vehicle in
sufficient time to avoid an accident.
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
airflow to cool the brakes more quickly. 130
Driving tips
Driving and parking

i
Hill start assist will aid you when pulling
away on a hill.
For further information, see "Hill start
assist" ( Y page 117).
Maximum gradient-climbing capability On good road surface conditions, the
maximum
gradient-climbing
capability is 80%,
which corresponds to an approach/
departure angle of 38°. Note that the
vehicle's gradient-climbing capability
depends on the off-road conditions.
Accelerate carefully and make sure that the
wheels do not spin when driving on steep
terrain.
i If the load on the front axle is reduced
when pulling away on a steep uphill slope,
the front wheels have a tendency to spin.
4ETS detects this and brakes the wheels
accordingly. The rear wheel torque is
increased, making it easier to drive off.
Brow of hill When driving on an uphill gradient, reduce
pressure slightly on the accelerator
immediately
before

reaching the top of the hill
(do not shift the transmission to position N).
Use the vehicle's own impetus to drive over
the top of the hill.
This style of driving prevents:
R the vehicle from lifting off the ground on the
brow of a hill
R loss of traction
R the vehicle from traveling too quickly down
the other side
Driving downhill R
Before tackling steep downhill gradients,
select shift range 1 (Y page 121).
This way you use the engine's braking
effect to reduce the speed. If this is not
sufficient, brake gently. When doing so, make sure that the vehicle is facing in the
direction of the line of fall.
R Observe the notes on driving in
mountainous terrain (Y page 139).
R Drive slowly.
R Do not drive at an angle down steep
inclines. Steer

into the line of fall and drive
with the front wheels aligned straight.
Otherwise, the vehicle could slip sideways,
tip and roll over.
R Check that the brakes are working normally
after a long downhill stretch.
i The special off-road ABS(Y page 54)
enables accurate, brief and repeated
locking of the front wheels, causing them
to dig into the loose ground. Note that when
the front wheels are fully braked, they slide
easily over the surface of the ground,
making it difficult to steer. Driving systems
Cruise control
Important safety notes Cruise control maintains a constant road
speed for you. On long and steep downhill
gradients, especially if the vehicle is laden,
you must select shift range 1, 2 or 3 in good
time. By doing so, you will make use of the
braking effect of the engine, which relieves
the load on the brake system and prevents
the
brakes

from overheating and wearing too
quickly.
Use cruise control only if road and traffic
conditions make it appropriate to maintain a
steady speed for a prolonged period. You can
set any road speed above 20 mph
(30 km/h). G
WARNING
The cruise control is a convenience system
designed to assist the driver during vehicle
operation. The driver is and must always Driving systems
139
Driving and parking
Z

You should have the brake fluid renewed at
regular intervals. The brake fluid change
intervals can be found in the Maintenance
Booklet.
Only use brake fluid approved by Mercedes-
Benz. Information about approved brake
fluids can be obtained from any authorized
Mercedes-Benz Center. Coolant
Important safety notes The coolant is a mixture of water and
antifreeze/corrosion inhibitor. It performs
the following tasks:
R
anti-corrosion protection
R antifreeze protection
R raising the boiling point
The engine cooling system is filled at the
factory with coolant which contains an
antifreeze/corrosion inhibitor that ensures
protection down to approximately -35 ‡
(-37 † ).
! Only add
coolant that has been premixed
with the desired antifreeze protection.
Otherwise, the engine could be damaged.
Further information on coolants and on
filling can be found in the Mercedes-Benz
Specifications for Service Products, MB
Approval 310.1, e.g. on the Internet at
http://bevo.mercedes-benz.com. You can
also consult an authorized Mercedes-Benz
Center.
! Always use a suitable coolant mixture,
even in countries where high temperatures
prevail.
Otherwise, the engine cooling system is not
sufficiently protected from corrosion and
the boiling point will be too low.
If the coolant has antifreeze protection down
to -35 ‡ (-37 † ), the boiling point of the
coolant in the pressurized system is
approximately 266 ‡ (130 † ). Your vehicle has a range of aluminum
components. Aluminum components in the
engine make it necessary to use
anticorrosion/antifreeze coolant which has
been specifically formulated to protect the
aluminum parts. Using other antifreeze/
corrosion inhibitors without these
characteristics affects the service life.
The
coolant

must be used throughout the year
in order to maintain the necessary corrosion
protection and provide protection from
overheating. In the Maintenance Booklet, you
can find information on the intervals for
renewal.
The renewal interval is determined by the
coolant type and the engine cooling system
design. The renewal interval in the
Maintenance Booklet is only valid if the
coolant is renewed or replenished with
Mercedes-Benz approved products.
Therefore, only use MB 326.0 antifreeze/
corrosion inhibitor or another Mercedes-Benz
approved product of the same specification.
Information on other products with the same
specifications that are approved by
Mercedes-Benz can be obtained at an
authorized Mercedes-Benz Center or on the
Internet at
http://bevo.mercedes-benz.com.
The coolant is checked at every maintenance
interval at an authorized Mercedes-Benz
Center.
The antifreeze/corrosion inhibitor
concentration in the engine cooling system
should:
R be at least 50%. This will protect the engine
cooling system against freezing down to
approximately -35 ‡ (-37 † ).
R not exceed 55% (antifreeze protection to
-49 ‡ [-45 † ]); otherwise, heat will not
dissipate as effectively.
If the coolant level is too low, MB 325.0
antifreeze/corrosion inhibitor should be
added. Have the engine cooling system
checked for possible leaks. 276
Service products and capacities
Technical data