
ClosingGWarning!
When closing the hood, use extreme caution
not to catch hands or fingers. Be careful that
you do not close the hood on anyone.
Make sure the hood is securely engaged
before driving off. Do not continue driving if
the hood can no longer engage after an
accident, for example. The hood could
otherwise come loose while the vehicle is in
motion and injure you and/or others.
XLet the hood drop from a height of
approximately 8 in (20 cm).
XCheck to make sure the hood is fully
closed.
If you can raise the hood at a point above
the headlamps, then it is not properly
closed. Open it again and let it drop with
somewhat greater force.
Engine oil
The amount of oil your engine consumes will
depend on a number of factors, including
driving style. Increased oil consumption can
occur when the vehicle is new or the vehicle
is driven frequently at higher engine speeds.
Engine oil consumption checks should only
be made after the vehicle break-in period.
! Do not use any special lubricant additives,
as these may damage the drive assemblies.
Using special additives not approved by
Mercedes-Benz may cause damage not
covered by the Mercedes-Benz Limited
Warranty.
For further information contact an
authorized Mercedes-Benz Center.
Notes on checking engine oil level
When checking the oil level
Rthe vehicle must be parked on level ground
Rwith the engine at operating temperature,
the vehicle must have been stationary for
at least 5 minutes with the engine turned
off
Rwith the engine not at operating
temperature, the vehicle must have been
stationary for at least 30 minutes with the
engine turned off
Checking engine oil level
XOpen the hood (Y page 214).XPull out oil dipstick :.XWipe oil dipstick : clean.XSlowly insert oil dipstick : fully into the
dipstick guide tube.
XPull out oil dipstick : again after
approximately 3 seconds to obtain
accurate reading.
The oil level is correct when it is between
lower (min) mark = and upper (max)
mark ; of oil dipstick :.
iThe filling quantity between the upper and
lower marks on the oil dipstick is
approximately 2.1 US qt. (2.0 l).
XIf necessary, add engine oil.
For more information on engine oil, see
“Fuels, coolants, lubricants etc.”
(Y page 334).
For information on messages in the
multifunction display concerning engine oil,
see the “Practical hints” section
(Y page 282).
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Adding engine oil
! Only use approved engine oils and oil
filters required for vehicles with
Maintenance System. For a listing of
approved engine oils and oil filters, contact
an authorized Mercedes-Benz Center or
visit www.mbusa.com (USA only).
The following will result in engine or
emission control system damage not
covered by the Mercedes-Benz Limited
Warranty:
RUsing engine oils and oil filters of
specification other than those expressly
required for the Maintenance System.
RChanging of oil and oil filter at change
intervals longer than those called for by
the Maintenance System.
RUsing any oil additives.
XUnscrew filler cap : from filler neck.XAdd engine oil as required. Be careful not
to overfill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.
! Excess oil must be siphoned or drained
off. It could cause damage to the engine
and emission control system not covered
by the Mercedes-Benz Limited Warranty.
XScrew filler cap : back on filler neck.
For more information on engine oil, see the
“Technical data” section (Y page 334) and
(Y page 335).
Transmission fluid level
The transmission fluid level does not need to
be checked. If you notice transmission fluid
loss or gearshifting malfunctions, have an
authorized Mercedes-Benz Center check the
transmission.
Coolant level
The engine coolant is a mixture of water and
anticorrosion/antifreeze.
When checking the coolant level, the vehicle
must be parked on level ground, and the
coolant temperature must be below 158‡
(70†).
GWarning!
In order to avoid any potentially serious burns:
RUse extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system, or
if the coolant temperature gauge indicates
that the coolant is overheated.
RDo not remove the cap on the coolant
expansion tank if the coolant temperature
is above 158‡ (70†). Allow the engine to
cool down before removing the cap. The
coolant expansion tank contains hot fluid
and is under pressure.
RUsing a rag, slowly open the cap
approximately 1/2 turn counterclockwise
to relieve excess pressure. If opened
immediately, scalding hot fluid and steam
will be blown out under pressure.
RDo not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts.
216Engine compartmentOperation
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Display messagesPossible causes/consequences and M Solutions4Check
Engine
Oil At
Next
RefuelingThe engine oil has dropped to a critical level.XCheck the engine oil level ( Y page 215) and add engine oil
as required ( Y page 216).XIf you must add engine oil frequently, have the engine
checked for possible leaks.If the message Check Engine Oil At Next
Refueling appears while the engine is
running and at operating temperature, the
engine oil level has dropped to approximately
the minimum level.
The message will be stored in the vehicle
status message memory after you have
cleared it from the multifunction display.
Visually check for oil leaks. If there are no
obvious oil leaks, drive to the nearest service
station to refill your engine oil to the required
level.For information on approved engine oils
contact an authorized Mercedes-Benz Center
or visit www.mbusa.com (USA only).
! Engine oil level warnings should not be
ignored. Extended driving with the symbol
displayed could result in serious engine
damage that is not covered by the
Mercedes-Benz Limited Warranty.Display messagesPossible causes/consequences and M SolutionsCThe fuel level is low.XRefuel at the next gas station.8Fuel
Level LowThe fuel level has dropped below the reserve mark.XRefuel at the next gas station.8Gas Cap
LooseA loss of pressure has been detected in the fuel system. The
fuel cap may not be closed properly or the fuel system may
be leaking.XCheck the fuel cap ( Y page 212).XIf it is not closed properly: Close the fuel cap.XIf it is closed properly: Have the fuel system checked at
an authorized Mercedes-Benz Center.282Vehicle status messages in the multifunction displayPractical hints
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Fuels, coolants, lubricants, etc.
Capacities
Vehicle components and their respective
lubricants must match. Therefore only use
products tested and approved by Mercedes-
Benz.
For information on tested and approved
products, contact an authorized Mercedes-
Benz Center or visit www.mbusa.com (USA
only).
GWarning!
Comply with all valid regulations with respect
to handling, storing, and disposing of service
fluids. Otherwise you could endanger persons
or the environment.
Keep service fluids out of the reach of
children.
For health reasons, you should prevent
service fluids from coming into direct contact
with your skin or clothing.
If a service fluid is swallowed, contact a
physician immediately.ModelCapacityFuels, coolants,
lubricants, etc.Engine with oil
filterAll models8.5 US qt (8.0 l)Approved engine
oilsAutomatic
transmissionGLK 350 269.5 US qt (9.0 l)MB Automatic
Transmission FluidGLK 350 4MATIC9.5 US qt (9.0 l)Front axleGLK 350 4MATIC0.63 US qt (0.6 l)Hypoid gear oil
(SAE 75W-85)Rear axleGLK 350 261.2 US qt (1.1 l)Hypoid gear oil
(SAE 75W-85)GLK 350 4MATIC1.1 US qt (1.0 l)Transfer caseGLK 350 4MATIC0.63 US qt (0.6 l)MB Automatic
Transmission FluidPower steeringAll modelsapprox. 1.1 US qt (1.0 l)MB Power Steering
Fluid (Pentosin
CHF 11.S)Brake systemAll models0.53 US qt (0.5 l)MB Brake Fluid
(DOT 4+)Cooling systemAll modelsapprox. 8.9 US qt (8.4 l)MB 325.0
Anticorrosion/
Antifreeze26 USA only.334Fuels, coolants, lubricants, etc.Technical data
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![MERCEDES-BENZ GLK350 4MATIC 2010 X204 Owners Manual ModelCapacityFuels, coolants,
lubricants, etc.Fuel tankAll models17.4 US gal (66.0 l)Premium unleaded
gasoline (Minimum
Posted Octane 91
[Avg. of
96 RON/86 MON])Fuel tank
reserveAll modelsapprox. 2. MERCEDES-BENZ GLK350 4MATIC 2010 X204 Owners Manual ModelCapacityFuels, coolants,
lubricants, etc.Fuel tankAll models17.4 US gal (66.0 l)Premium unleaded
gasoline (Minimum
Posted Octane 91
[Avg. of
96 RON/86 MON])Fuel tank
reserveAll modelsapprox. 2.](/manual-img/4/3527/w960_3527-336.png)
ModelCapacityFuels, coolants,
lubricants, etc.Fuel tankAll models17.4 US gal (66.0 l)Premium unleaded
gasoline (Minimum
Posted Octane 91
[Avg. of
96 RON/86 MON])Fuel tank
reserveAll modelsapprox. 2.1 US gal (8.0 l)Air
conditioning
systemAll models—R134a refrigerant
and special
PAG lubricant oil
(never R 12)Washer system
and headlamp
cleaning
systemAll models6.3 US qt (6.0 l)MB Windshield
Washer
Concentrate 27
( Y page 339)
Washer fluid mixing
ratio ( Y page 339)Approved engine oils
Engine oils are specifically tested for their
suitability in our engines and durability for our
service intervals. Therefore, only use
approved engine oils and oil filters required
for vehicles with the Maintenance System.
For a listing of approved engine oils and oil
filters, contact an authorized Mercedes-Benz
Center or visit www.mbusa.com (USA only).
! Using engine oils and oil filters of a
specification other than those expressly
required for the Maintenance System, or
changing of oil and oil filter at change
intervals longer than those called for by the
Maintenance System will result in engine or
emission control system damage not
covered by the Mercedes-Benz Limited
Warranty.
Please follow Maintenance System
recommendations for scheduled oil
changes. Failure to do so will result in
engine or emission control system damagenot covered by the Mercedes-Benz Limited
Warranty.
Mercedes-Benz recommends MOBIL OIL.
Use the table below to determine the
MB sheet number.ModelEngine,
typeMB sheet
numberGLK 350 28272229.5GLK 350 4MATIC272229.5
i
MB sheet numbers are printed on the
outside of oil containers.
27 Mixed with water or commercially available premixed washer solvent/antifreeze.
28 USA only.Fuels, coolants, lubricants, etc.335Technical dataX204_AKB; 3; 23, en-USd2ureepe,Version: 2.11.8.12009-07-16T19:16:58+02:00 - Seite 335Z

Viscosity grades for engine oils
Using the chart below, select oil viscosity
according to the lowest air temperature
expected before the next oil change.
Engine oil additives
! Do not blend oil additives with engine oil.
They may damage the engine. Damage or
malfunctions resulting from blending oil
additives are not covered by the Mercedes-
Benz Limited Warranty.
Air conditioning refrigerant
R134a (HFC) refrigerant and special PAG
lubricating oil are used in the air conditioning
system.
! Never use R 12 (CFC) or mineral-based
lubricating oil. Otherwise damage to the
system will occur.
Brake fluid
GWarning!
During vehicle operation, the boiling point of
the brake fluid is continuously reduced
through the absorption of moisture from the
atmosphere.
Under extremely strenuous operating
conditions, this moisture content can lead to
the formation of bubbles in the system, thus
reducing the system’s efficiency.
Therefore, the brake fluid must be replaced
regularly. Refer to your vehicle’s Maintenance
Booklet for replacement interval.
Only brake fluid approved by Mercedes-Benz
is recommended. Any authorized Mercedes-
Benz Center will provide you with additional
information.
Premium unleaded gasoline
GWarning!
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious
personal injury.
Never allow sparks, flames or smoking
materials near gasoline!
Turn off the engine before refueling.
Whenever you are around gasoline, avoid
inhaling fumes and any skin or clothing
contact. Extinguish all smoking materials.
Direct skin contact with fuels and the
inhalation of fuel vapors are damaging your
health.
! To maintain the engine’s durability and
performance, premium unleaded gasoline
must be used.
If premium unleaded gasoline is not
available and low octane gasoline is used,
follow these precautions:
RHave the fuel tank only partially filled
with unleaded regular gasoline and fill up
with premium unleaded gasoline as soon
as possible.
RAvoid full throttle driving and abrupt
acceleration.
RDo not exceed an engine speed of
3 000 rpm if the vehicle is loaded with a
light load such as two persons and no
luggage.
RDo not exceed 2/3 of maximum
accelerator pedal position if the vehicle
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is fully loaded or operating in
mountainous terrain.
Fuel requirements
Only use premium unleaded gasoline. The
octane number (posted at the pump) must be
91 min. It is an average of both the Research
Octane Number (RON) and the Motor Octane
Number (MON): (RON+MON)/2. This is also
known as the ANTI-KNOCK INDEX.
Reformulated gasolines (RFG) and/or
unleaded gasoline containing oxygenates
such as ethanol, TAME, ETBE, IPA, IBA, and
TBA can be used provided the ratio of any one
of these oxygenates to gasoline does not
exceed 10%; MTBE must not exceed 15%.
The ratio of methanol to gasoline must not
exceed 3% plus additional cosolvents.
Using mixtures of ethanol and methanol is not
allowed. Gasohol, which contains 10%
ethanol and 90% unleaded gasoline, can be
used.
These blends must also meet all other fuel
requirements, such as resistance to spark
knock, boiling range, vapor pressure, etc.
Gasoline additives
A major concern among engine
manufacturers is carbon build-up caused by
gasoline. Mercedes-Benz recommends only
the use of quality gasoline containing
additives that prevent the build-up of carbon
deposits.
After an extended period of using fuels
without such additives carbon deposits can
build up, especially on the intake valves and
in the combustion area, leading to engine
performance problems such as:
R Warm-up hesitation
R Unstable idle
R Knocking/pinging
RMisfire
R Power loss
In areas where carbon deposits may be
encountered due to lack of availability of
gasoline which contains these additives, the
use of Mercedes-Benz approved additives is
recommended.
Contact an authorized Mercedes-Benz Center
or visit www.mbusa.com (USA only) for a
listing of approved products. Follow
directions on the product label.
Do not blend other fuel additives with fuel.
This only results in unnecessary cost and may
be harmful to the engine operation.
! Damage or malfunction resulting from
poor fuel quality or from blending additional
fuel additives other than those tested and
approved by us for use on Mercedes-Benz
vehicles are not covered by the Mercedes-
Benz Limited Warranty or by any pre-owned
or Extended Limited Warranties.
Coolants
The engine coolant is a mixture of water and
anticorrosion/antifreeze, which provides:
R Corrosion protection
R Freeze protection
R Boiling protection (by increasing the boiling
point)
The cooling system was filled at the factory
with a coolant providing freeze protection to
approximately -35‡ (-37†) and corrosion
protection.
! Add premixed coolant solution only.
Adding water and MB 325.0 Anticorrosion/
Antifreeze separately from each other,
could cause engine damage not covered by
the Mercedes-Benz Limited Warranty.
If the antifreeze mixture is effective to -35‡
(-37† ), the boiling point of the coolant in the
pressurized cooling system is reached at
approximately 266‡ (130†).
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The coolant solution must be used year round
to provide the necessary corrosion protection
and increase boil-over protection. Refer to
the Maintenance Booklet for replacement
interval.
Coolant system design and coolant used
determine the replacement interval. The
replacement interval published in the
Maintenance Booklet is only applicable if
MB 325.0 Anticorrosion/Antifreeze solution
or other Mercedes-Benz approved products
of equal specification are used to renew the
coolant concentration or bring it back up to
the proper level.
For information on other Mercedes-Benz
approved products of equal specification,
contact an authorized Mercedes-Benz Center
or visit www.mbusa.com (USA only).
To provide important corrosion protection,
the solution must be at least 50%
anticorrosion/antifreeze (equivalent to
freeze protection to approximately -35‡
[-37†]).
If you use a solution that is more than 55%
anticorrosion/antifreeze (freeze protection
to approximately -49‡ [-45†]), the engine
temperature will increase due to the lower
heat transfer capability of the solution.
Therefore, do not use more than this amount
of anticorrosion/antifreeze.
If the coolant level is low, water and MB 325.0
Anticorrosion/Antifreeze should be used tobring it up to the proper level (have cooling
system checked for signs of leakage). Please
make sure the mixture is in accordance with
label instructions.
The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water.
If you are not sure about the water quality,
contact an authorized Mercedes-Benz
Center.
Anticorrosion/antifreeze
Your vehicle contains a number of aluminum
parts. The use of aluminum components in
motor vehicle engines necessitates that
anticorrosion/antifreeze coolant used in
such engines be specifically formulated to
protect the aluminum parts. Failure to use
such anticorrosion/antifreeze coolant will
result in a significantly shortened service life.
Therefore, the following product is strongly
recommended for use in your vehicle:
MB 325.0 Anticorrosion/Antifreeze agent.
Before the start of the winter season (or once
a year in hot southern regions), you should
have the anticorrosion/antifreeze
concentration checked.
The coolant is also regularly checked each
time you bring your vehicle to an authorized
Mercedes-Benz Center for service.
ModelApproximate freeze protection-35‡ (-37†)-49‡ (-45†)Cooling systemAll models4.4 US qt (4.2 l)4.9 US qt (4.6 l)338Fuels, coolants, lubricants, etc.Technical data
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