2018 MERCEDES-BENZ GLS engine overheat

X
Make sure that the windshield wipers are
turned off. X
Pull release lever C on the hood.
The hood is released.
X
Reach into the gap, pull hood catch handle D
up and lift the hood.
If you lift the hood by approximately 15 in
(40 cm), the hood is opened and held open
automatically by the gas-filled strut.
Closing the hood X
Lower the hood and let it fall from a height of
approximately 8 in (20 cm). X
Check that the hood has engaged properly.
If the hood can be raised slightly, it is not
properly engaged. Open it again and close it
with a little more force.
Radiator
Vehicles with a diesel engine: do not cover
the radiator. such as with a thermal mat or
insect protection cover. Otherwise, the values of
the European on-board diagnostics may be
affected. Some of these readings are required
by law and must be accurate at all times. Engine oil
Important safety notes
G WARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Where possible, let the engine cool down and
touch only the components described in the
following.
G WARNING
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.
G WARNING
If engine oil comes into contact with hot com-
ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Make sure that engine oil is not spilled next to
the filler neck. Let the engine cool down and
thoroughly clean the engine oil off the com-
ponents before starting the engine.
General notes Depending on your driving style, the vehicle
consumes up to 0.9 US qt (0.8 liters) of oil per
600 miles (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.
Depending on the engine, the oil dipstick may be
in a different location.326
Engine compartment
Maintenance and care

If standard unleaded gasoline is unavailable
and you have to refuel with unleaded gasoline
of a lower grade, observe the following pre-
cautions: R
Only fill the fuel tank to half full with regular
unleaded gasoline and fill the rest with pre-
mium-grade unleaded gasoline as soon as
possible. R
Do not drive at the maximum speed. R
Avoid sudden acceleration and engine
speeds over 3,000 rpm.
You will usually find information about the fuel
grade on the fuel pump. If you cannot find the
label on the fuel pump, ask the gas station staff.
i For more information, please contact a
qualified specialist workshop or visit
http://www.mbusa.com (USA only).
As a temporary measure, if the recommended
fuel is not available, you may also use regular
unleaded gasoline with an octane rating of
87 AKI/91 RON. This may reduce engine per-
formance and increase fuel consumption. Avoid
driving at full throttle and sudden acceleration.
Never refuel using gasoline with a lower AKI.
Information on refueling ( Y
page 156).
Additives
! Operating the engine with fuel additives
added later can lead to engine failure. Do not
mix fuel additives with fuel. This does not
include additives for the removal and preven-
tion of residue buildup. gasoline must only be
mixed with additives recommended by
Mercedes-Benz. Comply with the instructions
for use on the product label. More information
about recommended additives can be
obtained from any authorized Mercedes-Benz
Center.
Mercedes-Benz recommends that you use bran-
ded fuels that have additives.
The fuel quality available in some countries may
not be sufficient. Residue could build up in the
fuel injection system as a result. In such cases,
and in consultation with an authorized
Mercedes-Benz Center, the fuel may be mixed
with the cleaning additive recommended by
Mercedes-Benz. You must observe the notes
and mixing ratios specified on the container. Diesel Fuel grade
G WARNING
If you mix diesel fuel with gasoline, the flash
point is lower than that of pure diesel fuel.
When the engine is running, exhaust system
components could overheat without being
noticed. There is a risk of fire.
Never refuel with gasoline. Never mix gasoline
with diesel fuel.
! Only use Ultra Low Sulfur Diesel (ULSD),
otherwise it may lead to increased wear and
damage to the fuel system, engine and
exhaust system.
! Do not use the following: R
gasoline R
diesel with a bio-diesel content greater
than 5% (e.g. B20) R
bio-diesel R
vegetable oil R
paraffin R
kerosene R
marine diesel R
heating oil
Do not mix such fuels with diesel fuel and do
not use any special additives. Otherwise,
engine damage may occur.
! In countries outside USA and Canada, only
use sulfur-free diesel with a sulfur content
under 50 ppm. Otherwise, the emission con-
trol system could be damaged.
You will usually find information about the fuel
grade on the pump. If you cannot find the label
on the pump, ask the staff for assistance.
Information on refueling ( Y
page 156).
Low outside temperatures
i Diesel fuel with improved cold flow proper-
ties is available during the winter months.
Further information about fuel properties can
be obtained from oil companies, e.g. at gas
stations.388
Service products and filling capacities
Technical data

Gasoline engines MB-Freigabe or
MB-Approval
All models
229.5, 229.6
Mercedes ‑ AMG vehicles
229.5
Diesel engines MB-Freigabe or
MB-Approval
GLS 350 d 4MATIC
229.52
Mercedes-AMG vehicles: only use SAE 0W-40
or SAE 5W-40 engine oils.
i MB approval is indicated on the oil contain-
ers.
Filling capacities The following values refer to an engine oil
change, including the oil filter.
Model Capacity
GLS 350 d 4MATIC
8.5 US qt (8.0 l)
GLS 550 4MATIC
Mercedes ‑ AMG
vehicles 9.0 US qt (8.5 l)
Al l ot her models
7.4 US qt (7.0 l)
Ad ditives
! Do not use any additives in the engine oil.
This could damage the engine.
Brake fluid
G WARNING
The brake fluid constantly absorbs moisture
from the air. This lowers the boiling point of
the brake fluid. If the boiling point of the brake
fluid 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. Comply with the important safety notes for ser-
vice products when handling brake fluid
( Y
page 386).
Only use brake fluid approved for Mercedes-
Benz according to MB-Freigabe or MB-Approval
331.0.
Information about approved brake fluid can be
obtained at any qualified specialist workshop or
on the Internet at
http://bevo.mercedes-benz.com .
i Have the brake fluid regularly replaced at a
qualified specialist workshop in accordance
with the replacement intervals and the
replacement confirmed in the service report.
Coolant
Important safety notes
G WARNING
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 Ser-
vice 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.
i Have the coolant regularly replaced at a
qualified specialist workshop and the replace-
ment confirmed in the service report.
Comply with the important safety notes for ser-
vice products when handling coolant
( Y
page 386).390
Service products and filling capacities
Technical data