
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.
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XUsing a rag, slowly open cap :
approximately 1/2 turn counterclockwise
to relieve excess pressure.
XContinue turning cap : counterclockwise
and remove it.
The coolant level is correct if the level
Rfor cold coolant: reaches marking bar
= in coolant expansion tank ;
Rfor warm coolant: is approximately 0.6 in
(1.5 cm) higher
XAdd coolant as required.XScrew cap : back on and tighten it.
For more information on coolant, see the
“Technical data” section (Y page 334) and
(Y page 337).
Washer system and headlamp
cleaning system
GWarning!
Washer solvent/antifreeze is highly
flammable. Do not spill washer solvent/
antifreeze on hot engine parts, because it may
ignite and burn. You could be seriously
burned.
! Always use washer solvent/antifreeze
where temperatures may fall below
freezing point. Failure to do so could result
in damage to the washer system/fluid
reservoir.
! Only use washer fluid which is suitable for
plastic lenses. Improper washer fluid can
damage the plastic lenses of the
headlamps.
! Do not use distilled or deionized water in
the washer fluid reservoir. Otherwise, the
washer fluid level sensor could be
damaged.
Fluid for the washer system, rear window
washer system, and the headlamp cleaning
system is supplied from the washer fluid
reservoir.
During all seasons, use MB Windshield
Washer Concentrate “MB SummerFit”. Mix it
with water or premixed washer solvent/
antifreeze depending on the ambient
temperature (Y page 339).
XOpening washer fluid reservoir: Pull tab
of cap : upwards.
XRefill the washer fluid reservoir.XClosing washer fluid reservoir: Press
cap : onto filler hole until it engages.
For more information, see “Washer system
and headlamp cleaning system”
(Y page 335).
Brake fluid level
! If you find that the brake fluid in the brake
fluid reservoir has fallen to the minimum
mark or below, have the brake system
checked for brake pad thickness and leaks
immediately. Contact an authorized
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The Tire and Loading Information placard lists
the recommended cold tire inflation
pressures : for maximum loaded vehicle
weight. The tire inflation pressures listed
apply to the tires installed as original
equipment.
Important notes on tire inflation
pressure
GWarning!
If the tire inflation pressure drops repeatedly,
check the tires for punctures from foreign
objects and/or whether air is leaking from the
valves or from around the rim.
Tire temperature and tire inflation pressure
are also increased while driving, depending
on the driving speed and the tire load.
If you will be driving your vehicle at high
speeds of 100 mph (160 km/h) or higher,
where it is legal and conditions allow, consult
the tire inflation pressure label on the inside
of the fuel filler flap on how to adjust the cold
tire inflation pressure. If you do not adjust the
tire inflation pressure, excessive heat can
build up and result in sudden tire failure.
If you are not sure about the proper tire
inflation pressure, contact an authorized
Mercedes-Benz Center.
iDriving comfort may be reduced when the
tire inflation pressure is adjusted to the
value for speeds above 100 mph
(160 km/h) as specified on the tire inflation
pressure label located on the inside of the
fuel filler flap.
Make sure to readjust the tire inflation
pressure for normal driving speeds.
Supplemental tire inflation pressure
information for different loading conditions of
the vehicle can be found on the tire inflation
pressure label. The tire inflation pressure
label is located on the inside of the fuel filler
flap.
For the tire inflation pressure for spare
wheels such as Minispare wheels or spare
wheels with collapsible tire refer to
Rthe yellow label on the spare wheel rim
Rthe “Technical data” section of this
Operator’s Manual (Y page 333)
Rthe Tire and Loading Information placard on
the driver’s door B-pillar
Unless specified otherwise, the tire inflation
pressures on the tire inflation pressure label
are valid for all approved, factory-equipped
tires.
iData shown on tire inflation pressure
label examples are for illustration purposes
only. Tire inflation pressure data are
specific to each vehicle and may vary from
data shown in the following illustrations.
Refer to the tire inflation pressure label on
vehicle for actual data specific to your
vehicle.
Example illustration: Tire inflation pressures for allapproved, factory equipped tires
When a tire size is specified, the tire inflation
pressure that follows applies to that
particular tire size only.
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Weight Rating (GVWR) and the Gross Axle
Weight Rating (GAWR) for either the front or
rear axle. You can obtain the GVWR and
GAWR from the certification label. The
certification label can be found on the driver’s
door B-pillar, see the “Technical data” section
(Y page 328).
Gross Vehicle Weight Rating (GVWR): The
total weight of the vehicle, all occupants, all
cargo, and the trailer tongue load (if
applicable) must never exceed the GVWR.
Gross Axle Weight Rating (GAWR): The total
allowable weight that can be carried by a
single axle (front or rear).
To assure that your vehicle does not exceed
the maximum permissible weight limits
(GVWR and GAWR for front and rear axle),
have the loaded vehicle (including driver,
passengers and all cargo and, if applicable,
trailer fully loaded) weighed on a suitable
commercial scale.
Trailer tongue load
The tongue load of any trailer is an important
weight to measure because it affects the load
you can carry in your vehicle. If a trailer is
towed, the tongue load must be added to the
weight of all occupants riding and any cargo
you are carrying in the vehicle. The tongue
load typically is 8% of the trailer weight and
everything loaded in it.
Maximum tire load
GWarning!
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver’s door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
The maximum tire load rating : is the
maximum weight the tires are designed to
support.
For more information on tire load rating, see
(Y page 236).
For information on calculating total and cargo
load capacities, see (Y page 228).
Direction of rotation
Unidirectional tires offer added advantages,
such as better hydroplaning performance. To
benefit, however, you must make sure the
tires rotate in the direction specified.
An arrow on the sidewall indicates the
intended direction of rotation of the tire.
Spare wheels may be mounted against the
direction of rotation (spinning) even with a
unidirectional tire for temporary use only until
the regular drive wheel has been repaired or
replaced. Always observe and follow
applicable temporary use restrictions and
speed limitations indicated on the spare
wheel.
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IndexSpeed ratingHup to 130 mph (210 km/h)Vup to 149 mph (240 km/h)Wup to 168 mph (270 km/h)Yup to 186 mph (300 km/h)ZR...Yup to 186 mph (300 km/h)ZR...(..Y)above 186 mph (300 km/h)ZRabove 149 mph (240 km/h)
RAt the tire manufacturer’s option, any tire
with a speed capability above 149 mph
(240 km/h) can include a “ZR” in the size
designation (for example: 245/40 ZR18).
To determine the maximum speed
capability of the tire, the service
description for the tire must be referred to.
The service description is comprised of
load index A and speed symbol B.
If your tire includes “ZR” in the size
designation and no service description is
given, the tire manufacturer must be
consulted for the maximum speed
capability.
If a service description is given, the speed
capability is limited by the speed symbol in
the service description. Example:
245/40 ZR18 97Y. In this example, “97Y”
is the service description. The letter “Y”
designates the speed rating and the speed
capability of the tire is limited to 186 mph
(300 km/h).
R Any tire with a speed capability above
186 mph (300 km/h) must include a “ZR”
in the size designation AND the service
description must be placed in parenthesis.
Example: 275/40 ZR 18 (99Y). The “(Y)”
speed symbol in parenthesis designates
the maximum speed capability of the tire
as being above 186 mph (300 km/h).
Consult the tire manufacturer for the actual
maximum permissible speed of the tire.
All-season and winter tiresIndexSpeed ratingQ M+S 10up to 100 mph (160 km/h)T M+S10up to 118 mph (190 km/h)H M+S 10up to 130 mph (210 km/h)V M+S10up to 149 mph (240 km/h)
i
Not all M+S rated tires provide special
winter performance. Make sure the tires
you use show M+S and the mountain/
snowflake imarking on the tire
sidewall. These tires meet specific snow
traction performance requirements of the
Rubber Manufacturers Association (RMA)
and the Rubber Association of Canada
(RAC) and have been designed specifically
for use in snow conditions.
An electronic speed limiter prevents your
vehicle from exceeding a speed of 130 mph
(210 km/h).
The factory equipped tires on your vehicle
may have a tire speed rating above the
maximum speed permitted by the electronic
speed limiter.
Make sure your tires have the required tire
speed rating as specified for your vehicle in
the “Technical data” section ( Y page 331),
for example when purchasing new tires.
If you are uncertain about the correct reading
of the information given on a tire’s sidewall,
any authorized Mercedes-Benz Center will be
glad to assist you.
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GWarning!
If you use your spare wheel when winter tires
are fitted on the other wheels, be aware that
the difference in tire characteristics may very
well impair turning stability and that overall
driving stability may be reduced. Adapt your
driving style accordingly.
Have the spare wheel replaced by a regular
road wheel with a winter tire at the nearest
authorized Mercedes-Benz Center.
Always use winter tires at temperatures
below 45‡ (7†) and whenever wintry road
conditions prevail. Not all M+S rated tires
provide special winter performance. Make
sure the tires you use show the mountain/
snowflake imarking on the tire sidewall.
These tires meet specific snow traction
performance requirements of the Rubber
Manufacturers Association (RMA) and the
Rubber Association of Canada (RAC) and
have been designed specifically for use in
snow conditions. Use of winter tires is the
only way to achieve the maximum
effectiveness of your vehicle’s driving safety
systems such as the ABS and the ESP ®
in
winter operation.
For safe handling, make sure all mounted
winter tires are of the same make and have
the same tread design.
For information on winter tires for your
vehicle model, see the “Technical data”
section ( Y page 331).
Always observe the speed rating of the winter
tires installed on your vehicle.
After installing winter tires:
XCheck the tire inflation pressure and adjust
it if necessary ( Y page 221).XRestart the tire pressure loss warning
system ( Y page 222) or the Advanced Tire
Pressure Monitoring System (Y page 224).Snow chains
! Some tire sizes do not leave adequate
clearance for snow chains. To help avoid
serious damage to your vehicle or tires,
make sure the use of snow chains is
permissible as specified in the “Technical
data” section of this Operator’s Manual.
Snow chains should only be driven on snow-
covered roads at speeds not to exceed
30 mph (50 km/h). Remove chains as soon
as possible when driving on roads without
snow.
Observe the following guidelines when using
snow chains:
R Use of snow chains is not permissible with
all wheel/tire combinations ( Y page 331).
R Use snow chains in pairs and on rear
wheels only. Follow the manufacturer’s
mounting instructions.
! If snow chains are mounted to the front
wheels, they may scrape against the body
or axle components. The tires or the vehicle
could be damaged as a result.
R Only use snow chains that are approved by
Mercedes-Benz. Any authorized Mercedes-
Benz Center will be glad to advise you on
this subject.
R Use of snow chains may be prohibited
depending on location. Always check local
and state laws before installing snow
chains.
R Do not use snow chains on the spare wheel.
i When driving with snow chains, you may
wish to switch off the ESP ®
(Y page 61)
before setting the vehicle in motion. This
will improve the vehicle’s traction.242Winter drivingOperation
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Vehicle equipment ............................328
Parts service .....................................328
Warranty coverage ...........................328
Identification labels ..........................328
Vehicle specification GLK 350
(204.956) ...........................................330
Vehicle specification GLK 350
4MATIC (204.987) .............................330
Rims and tires ...................................331
Fuels, coolants, lubricants, etc. ......334
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Vehicle equipment
iThis Operator’s Manual describes all
features, standard or optional, potentially
available for your vehicle at the time of
purchase. Please be aware that your
vehicle might not be equipped with all
features described in this manual.
Parts service
All authorized Mercedes-Benz Centers
maintain a stock of Genuine Mercedes-Benz
Parts required for maintenance and repair
work. In addition, strategically located parts
distribution centers provide quick and
reliable parts service.
More than 300 000 different parts for
Mercedes-Benz models are available.
Genuine Mercedes-Benz Parts are subjected
to stringent quality inspections. Each part has
been specifically developed, manufactured or
selected for and adapted to Mercedes-Benz
vehicles.
Therefore, Genuine Mercedes-Benz Parts
should be installed.
! Do not use non-genuine Mercedes-Benz
parts and accessories not authorized by
Mercedes-Benz. Doing so could damage
the vehicle, which is not covered by the
Mercedes-Benz Limited Warranty. Also, it
could compromise the vehicle’s durability
or safety.
Warranty coverage
Your vehicle is covered under the terms of the
warranties printed in the Service and
Warranty Information booklet.
Your authorized Mercedes-Benz Center will
exchange or repair any defective parts
originally installed in the vehicle in
accordance with the terms of the following
warranties:
RNew Vehicle Limited Warranty
REmission System Warranty
REmission Performance Warranty
RCalifornia, Connecticut, Maine,
Massachusetts, New York, Pennsylvania,
Rhode Island, and Vermont Emission
Control Systems Warranty
RState Warranty Enforcement Laws (Lemon
Laws)
Replacement parts and accessories are
covered by the Mercedes-Benz Parts and
Accessories warranties, copies of which are
available at any authorized Mercedes-Benz
Center.
Loss of Service and Warranty
Information booklet
Should you lose your Service and Warranty
Information booklet, have an authorized
Mercedes-Benz Center arrange for a
replacement. It will be mailed to you.
Identification labels
328Identification labelsTechnical data
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