2015 MERCEDES-BENZ G-CLASS SUV engine overheat

Useful information
iThis Operator's Manual describes all
models and all standard and optional equip- ment of your vehicle available at the time of
publication of the Operator's Manual.
Country-specific differences are possible.
Please note that your vehicle may not be
equipped with all features described. This
also applies to safety-related systems and
functions.
iRead the information on qualified special-
ist workshops: ( Ypage 28).
Engine compartment
Hood
Important safety notes
GWARNING
If the hood is unlatched, it may open up when the vehicle is in motion and block your view.
There is a risk of an accident.
Never unlatch the hood while driving. Before
every trip, ensure that the hood is locked.
GWARNING
Certain components in the engine compart-
ment may be very hot, e.g. the drive system
and radiator. Working in the engine compart-
ment poses a risk of injury.
If possible, let the drive system cool down andonly touch the components described in the following.
GWARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department.
GWARNING
The ignition system and the fuel injection sys-tem work under high voltage. If you touch
components which are under voltage, you
could get an electric shock. There is a risk of
injury.
Never touch components of the ignition sys-
tem or fuel injection system when the ignition is switched on.
GWARNING
The engine compartment contains moving
components. Certain components, such as
the radiator fan, may continue to run or start
again suddenly when the ignition is off. There is a risk of injury.
If you need to do any work inside the engine
compartment:
R switch off the ignition
R never reach into the area where there is a
risk of danger from moving components,
such as the fan rotation area
R remove jewelry and watches
R keep items of clothing and hair, for exam-
ple, away from moving parts
GWARNING
When the hood is open and the windshield
wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windshield wipers and
the ignition before opening the hood.
!Make sure that the windshield wipers are
not folded away from the windshield. You
could otherwise damage the windshield
wipers or the hood.
Do not touch the following when the ignition
is switched on: R ignition coils
R spark plug connectors
R test socket
204Engine compartment
Maintenance and care

Brake fluid
GWARNING
The brake fluid constantly absorbs moisture
from the air. This lowers the boiling point of
the brake fluid. If the boiling point of the brakefluid is too low, vapor pockets may form in the brake system when the brakes are applied
hard. This would impair braking efficiency.
There is a risk of an accident.
You should have the brake fluid renewed at
the specified intervals.
When handling brake fluid, observe the
important safety notes on service products( Y page 259).
The brake fluid change intervals can be found
in the Maintenance Booklet.
Only use brake fluid approved by Mercedes-
Benz according to MB Approval 331.0.
Information about approved brake fluid can
be obtained at any qualified specialist work-
shop or on the Internet at
http://bevo.mercedes-benz.co m.
iHave the brake fluid regularly replaced at
a qualified specialist workshop and the
replacement confirmed in the Maintenance Booklet.
Coolant
Important safety notes
GWARNING
If antifreeze comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Let the engine cool down before you add anti-
freeze. Make sure that antifreeze is not spilled
next to the filler neck. Thoroughly clean the
antifreeze from components before starting
the engine.
!Only add coolant that has been premixed
with the desired antifreeze protection. You
could otherwise damage the engine. Further information on coolants can be
found in the Mercedes-Benz Specifications
for Service Products, MB BeVo 310.1, e.g.
on the Internet at
http://bevo.mercedes-benz.com. Or con-
tact a qualified specialist workshop.
!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
overheating.
iHave the coolant regularly replaced at a
qualified specialist workshop and the
replacement confirmed in the Maintenance Booklet.
Comply with the important safety precautions for service products when handling coolant( Y page 259).
The coolant is a mixture of water and anti-
freeze/corrosion inhibitor. It performs the
following tasks:
R corrosion protection
R antifreeze protection
R raising the boiling point
If the coolant has antifreeze protection down to -35 ‡(-37 †), the boiling point of the cool-
ant in the pressurized system is approx-
imately 266 ‡ (130 †).
The antifreeze/corrosion inhibitor concentra- tion 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 protectiondo wn to -49 ‡ [-45 †]). Otherwise, heat
will not be dissipated as effectively.
Mercedes-Benz recommends an antifreeze/
corrosion inhibitor in accordance with MB
Specifications for Service Products 310.1.
iWhen the vehicle is first delivered, it is fil-
led with a coolant mixture that ensures
adequate antifreeze and corrosion protec-
tion.
264Service products and filling capacities
Technical data

iThe coolant is checked with every main-
tenance interval at a qualified specialist workshop.
The engine cooling system is filled with cool-
ant at the factory which contains antifreeze/
corrosion inhibitor that ensures protection
down to approximately -35 ‡ (-37 †).
Your vehicle has a range of aluminum com-
ponents. Aluminum components in the
engine make it necessary to use antifreeze/
corrosion inhibitor that has been specifically
formulated to protect the aluminum parts.
Failure to use such anticorrosion/antifreeze
coolant will result in a significantly shortened service life.
The coolant must be used throughout the year
in order to maintain the necessary corrosion
protection and to provide protection from
overheating. In the Maintenance Booklet, you
can find information on the intervals forrenewal.
The renewal interval is determined by the
coolant type and the engine cooling system
design. The renewal interval in the Mainte-
nance Booklet is only valid if the coolant is
renewed or added to 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 author- ized Mercedes-Benz Center or on the Internet
at http://bevo.mercedes-benz.com .
If the coolant level is too low, MB 325.0 anti-
freeze/corrosion inhibitor should be added.
Have the engine cooling system checked for
possible leaks.Capacity
ModelCapacity
G 550Approx. 11.1 US qt
(10.5 l)
G 63 AMGApprox. 14.6 US qt
(13.8 l)
Low-temperature
circuit: approx-
imately 3.1 US qt
(2.9 l)
iUse MB 325.0 or MB 326.0 antifreeze/
corrosion inhibitor.
Windshield/headlamp cleaning sys- tem
Important safety notes
GWARNING
Windshield washer concentrate could ignite if it comes into contact with hot engine compo-
nents or the exhaust system. There is a risk of
fire and injury.
Make sure that no windshield washer con-
centrate is spilled next to the filler neck.
!Only use washer fluid that is suitable for
plastic lamp lenses, e.g. MB SummerFit or
MB WinterFit. Unsuitable washer fluid
could damage the plastic lenses of theheadlamps.
!Do not add distilled or de-ionized water to
the washer fluid container. Otherwise, the
level sensor may be damaged.
!Only MB SummerFit and MB WinterFit
washer fluid should be mixed together. The spray nozzles may otherwise becomeblocked.
Service products and filling capacities265
Technical data
Z