message will appear in the multifunction
display.GWarning
If the Check Tire Pressure Soon message
appears in the multifunction display, one or
more tires are significantly underinflated.
Stop the vehicle as soon as possible and
inflate the tires to the pressure specified on
the vehicle's Tire and Loading Information
placard or (where available) in the tire
pressure table.
Driving on a significantly underinflated tire
causes the tire to overheat and can lead to
tire failure. Underinflation also reduces fuel
efficiency and tire tread life, and may affect
the vehicle's handling and stopping ability.
Check all tires when cold, including the spare
tire, at least once a month. The tires should
be inflated to the recommended pressure.
This information can be found:
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
or
R in the table for the tire pressure on the
inside of the fuel filler flap
GWarning!
The tire pressure loss warning system does
not provide a warning for wrongly selected tire
inflation pressures. Always adjust tire
inflation pressure according to the Tire and
Loading Information placard on the driver's
door B-pillar or on the tire inflation pressure
label located on the inside of the fuel filler flap.
The tire pressure loss warning system does
not replace regular checks of the tire inflation
pressures since a gradual pressure loss in
more than one tire cannot be detected by the
tire pressure loss warning system.
The tire pressure loss warning system is not
able to issue a warning due to a sudden
dramatic loss of tire inflation pressure (e.g.
tire blowout caused by a foreign object). In
this case bring the vehicle to a halt by carefully
applying the brakes and avoiding abrupt
steering maneuvers.
The function of the tire pressure loss warning
system is limited or delayed if:
R snow chains are mounted on your vehicle.
R road conditions are wintry.
R you are driving on sand or gravel.
R you adopt a very sporty driving style
(cornering at high speeds or driving with
high rates of acceleration).
R you are towing a very heavy or large trailer.
R you are driving with a heavy cargo (in the
vehicle or on the roof).
Restarting the tire pressure loss
warning system
Restart the tire pressure loss warning system
if you have:
R changed the tire pressure
R changed the wheels or tires
R mounted new wheels or tires
XBefore restarting, refer to the Tire and
Loading Information placard on the
B-pillar on the driver's side or the tire
pressure table on the inside of the fuel filler
flap to ensure the tire pressure in all four
tires is set correctly for the current
operating conditions.XObserve the notes in the section on tire
pressures ( Y page 266).GWarning
The tire pressure loss warning system can
only give reliable warnings if you have set the
correct tire pressure.
If an incorrect tire pressure is set, these
incorrect values will be monitored.
A tire with insufficient pressure results in
vehicle instability when driving, thus
increasing the risk of an accident.
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XMake sure that the SmartKey is in
position 2 ( Y page 129) in the ignition lock.XPress the = or ; button to select the
Service menu.XPress the 9 or : button to select
Tire Pressure .XPress the a button.
The Run Flat Indicator Active
Press 'OK' to Restart message
appears in the multifunction display.
If you wish to confirm the restart:
XPress the a button.
The Tire Pressure Now OK? message
appears in the multifunction display.XPress 9 or : to select Yes.XPress the a button.
The Run Flat Indicator Restarted
message appears in the multifunction
display.
After a teach-in period, the tire pressure
loss warning system will monitor the set
tire pressures of all four tires.
If you wish to cancel the restart:
XPress the % button.
or
XIf the message: Tire Pressure now OK?
appears, use 9 or : to select
Cancel .XPress the a button.
The tire pressure values stored at the last
restart will continue to be monitored.
Tire pressure monitoring system
(USA only)
Important safety notes
If a tire pressure monitor is installed, the
vehicle's wheels have sensors installed that
monitor the tire pressures in all four tires. The
tire pressure monitor warns you when the
pressure drops in one or more of the tires. The
tire pressure monitor only functions if the
correct wheel electronics units are installed
in all wheels.
The tire pressure monitor has a yellow
warning lamp in the instrument cluster for
indicating a pressure loss or malfunction.
Depending on how the warning lamp flashes
or lights up, a tire pressure that is too low or
a malfunction in the tire pressure monitor is
displayed:
R if the warning lamp is lit continuously, the
tire pressure on one or more tires is
significantly too low. The tire pressure
monitor is not malfunctioning.
R if the warning lamp flashes for 60 seconds
and then remains lit constantly, the tire
pressure monitor is malfunctioning.GWarning!
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the inflation
pressure recommended by the vehicle
manufacturer on the tire and loading
information table on the driver's door B-pillar
or the tire inflation pressure table on the
inside of the fuel filler flap. If your vehicle has
tires of a different size than the size indicated
on the tire and loading information table or
the tire inflation pressure table, you should
determine the proper tire inflation pressure
for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitor
(TPMS). An indicator lamp lights up if one or
more of your tires are significantly
underinflated. Accordingly, when the low tire
pressure indicator lamp lights up, you should
stop and check your tires as soon as possible,
and inflate them to the proper pressure.
Driving on a significantly underinflated tire
causes the tire to overheat and can lead to
tire failure.
Underinflation also reduces fuel efficiency
and tire tread life and may affect the vehicle's
handling and stopping ability. Please note that
the TPMS is not a substitute for proper tire
maintenance and it is the driver's
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of the tire pressure display. The tire pressures
are already being monitored.
i If a spare wheel/emergency spare wheel
is mounted, the system may continue to
show the tire pressure of the wheel that has
been removed for a few minutes. If this
occurs, note that the value displayed for
the position where the spare wheel is
mounted is not the same as the spare
wheel/emergency spare wheel's current
tire pressure.
TPMS warning messages
If the tire pressure monitor detects a
significant pressure loss on one or more tires,
a warning message is shown in the
multifunction display. A warning tone also
sounds and the tire pressure warning lamp
lights up in the instrument cluster.
Each tire that is affected by a significant loss
of pressure is highlighted by a red rectangle.
If the Correct Tire Pressure message
appears in the multifunction display:
XCheck the tire pressure on all four wheels
and correct it if necessary.
i If the wheel positions on the vehicle are
interchanged, the tire pressures may be
displayed for the wrong positions for a
short time. This is rectified after a few
minutes of driving, and the tire pressures
are displayed for the correct positions.
Restarting the tire pressure monitor
GWarning
It is the driver's responsibility to set the tire
inflation pressure to the recommended cold
tire inflation pressure. Underinflated tires
affect the ability to steer or brake the vehicle.
You might lose control over the vehicle.
When you restart the tire pressure monitor,
all existing warning messages are deleted and
the warning lamps go out. The monitor uses
the currently set tire pressures as the
reference values for monitoring.
The TPMS must be restarted when you set the
tire pressure to a new value (as a result of
changed handling or load characteristics, for
example). The TPMS then monitors the new
tire pressure values.
Restart the tire pressure monitor after you
have set the tire pressure to the value
recommended for the desired driving
situation ( Y page 266). Only correct tire
pressures on cold tires. Comply with the
recommended tire pressures on the Tire and
Loading Information placard on the B-pillar on
the driver's side Additional tire pressure
values for driving at high speeds or with heavy
loads can be found in the Tire Pressure table
on the inside of the fuel filler flap.XMake sure that the tire pressure is correct
on all four wheels.XMake sure that the SmartKey is in position
2 in the ignition lock.XPress the = or ; button to select the
Service menu.XPress the 9 or : button to select
Tire Pressure .XPress the a button.
The current tire pressure of each wheel or
the Tire pressures will be
displayed after driving a few
minutes message is shown in the
multifunction display.XPress the : button.
The Use Current Pressures as New
Reference Values message appears in
the multifunction display.
If you wish to confirm the restart:
XPress the a button.
The Tire Press. Monitor Restarted
message appears in the multifunction
display.
After driving for a few minutes, the system
checks whether the current tire pressures
are within the specified range. The new tireTire pressures273Tires and wheelsBA 204.9 USA, CA Edition A 2011; 1; 6, en-USd2mwentsVersion: 3.0.3.62010-06-15T08:58:39+02:00 - Seite 273Z
Trailer load/noseweight
The trailer load/noseweight affects the gross
weight of the vehicle. If a trailer is attached,
the trailer load/noseweight is included in the
load along with occupants and luggage. The
trailer load/noseweight is usually
approximately 8% of the gross weight of the
trailer and its cargo.
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.
i The actual values for tires are specific to
each vehicle and may deviate from the
values in the illustration.
Maximum tire load : is the maximum
permitted weight for which the tire is
approved.
Further information on tire loads
( Y page 280).
Direction of rotation
Tires with a specified direction of rotation
have additional benefits, e.g. if there is a risk
of hydroplaning. You will only gain these
benefits if the correct direction of rotation is
observed.
An arrow on the sidewall of the tire indicates
its correct direction of rotation.
You may mount an emergency spare wheel/
spare wheel against the direction of rotation.
Observe the time restriction on use as well as
the speed limitation specified on the
emergency spare wheel/spare wheel.
Uniform Tire Quality Grading
Standards
Overview of tire quality standards
The Uniform Tire Quality Grading Standards
are U.S. government specifications. Their
purpose is to provide drivers with uniform
reliable information on tire performance data.
Tire manufacturers have to grade tires using
three performance factors: : tread
wear, ; tire traction, and = heat resistance.
All tires sold in North America are provided
with the corresponding quality class mark on
the sidewall of the tire, even though these
regulations do not apply to Canada.
i The actual values for tires are specific to
each vehicle and may deviate from the
values in the illustration.
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car tires must meet under Federal Motor
Vehicle Safety Standard No. 109. Grades B
and A represent higher levels of performance
on the laboratory test wheel than the
minimum required by law.
Interchanging the wheels
GWarning
Rotate front and rear wheels only if the tires
are of the same dimension.
If your vehicle is equipped with mixed-size
tires (different tire dimensions front vs. rear),
tire rotation is not possible.
GWarning!
Have the tightening torque checked after
changing a wheel. The wheels could come
loose if they are not tightened to a torque of
110 lb-ft (150 Nm).
Only use genuine Mercedes-Benz wheel bolts
specified for your vehicle’s rims.
The wear patterns on the front and rear tires
differ, depending on the operating conditions.
Rotate the wheels before a clear wear pattern
has formed on the tires. Front tires typically
wear more on the shoulders and the rear tires
in the center.
If your vehicle's tire configuration allows, you
can rotate the wheels according to the
intervals in the tire manufacturer's warranty
book in your vehicle documents. If no
warranty book is available, the tires should be
rotated every 3000 to 6000 miles
(5000 to 10000 km), or earlier if tire wear
requires. Do not change the direction of
wheel rotation.
Clean the contact surfaces of the wheel and
the brake disc thoroughly every time a wheel
is rotated. Check the tire pressures.
Information on changing a wheel and
mounting the spare wheel ( Y page 247).
Tire labeling
Overview of tire labeling
The following markings are on the tire in
addition to the tire name (sales designation)
and the manufacturer's name:
:Uniform Tire Quality Grading Standard
( Y page 284);DOT, Tire Identification Number
( Y page 283)=Maximum tire load ( Y page 278)?Maximum tire pressure ( Y page 274)AManufacturerBTire material ( Y page 284)CTire size designation, load-bearing
capacity and speed index ( Y page 281)DLoad index ( Y page 283)ETire name
i
Tire data is vehicle-specific and may
deviate from the data in the example.
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Tire size designation, load-bearing
capacity and speed index:Tire width;Aspect ratio in percent=Tire code?Rim diameterALoad bearing indexBSpeed index
i Tire data is vehicle-specific and may
deviate from the data in the example.
General: depending on the manufacturer's
standards, the size imprinted in the tire wall
may not contain any letters or may contain
one letter that precedes the size description.
If there is no letter preceding the size
description (as shown above): passenger
vehicle tires according to European
manufacturing standards.
If "P" precedes the size description:
passenger vehicle tires according to U.S.
manufacturing standards.
If "LT" precedes the size description: light
truck tires according to U.S. manufacturing
standards.
If "T" precedes the size description: compact
emergency spare wheels at high tire
pressure, only for temporary use in an
emergency.
Tire width: tire width : shows the nominal
tire width in millimeters.
Aspect ratio: aspect ratio ; is relationship
between tire height and tire width and is
specified in percent. The aspect ratio is
calculated by dividing the tire width by the tire
height.
Tire code: tire code = specifies the tire type.
"R" represents radial tires. "D" represents
diagonal tires, "B" represents diagonal radial
tires.
Optionally, tires with a maximum speed of
over 149 mph (240 km/h) may have "ZR" in
the size description depending on the
manufacturer (e.g. 245/40 ZR 18).
Rim diameter: rim diameter ? is the
diameter of the bead seat, not the diameter
of the rim flange. The rim diameter is
specified in inches (in).
Load bearing index: load bearing index A
is a numerical code that specifies the
maximum load-bearing capacity of a tire.GWarning
The tire load rating must always be at least
half of the GAWR of your vehicle. Otherwise,
sudden tire failure may be the result which
could cause an accident and/or serious injury
to you or others.
Always replace rims and tires with rims and
tires having the same specifications
(designation, manufacturer and type) as
shown on the original part.
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.
Example:
The load bearing index 91 is equivalent to a
maximum load of 1356 lbs (615 kg) that the
tire can carry. For further information on the
maximum tire load in kilograms and pounds,
see ( Y page 278).
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Wheel rim
The part of the wheel on which the tire is
mounted.
GAWR (Gross Axle Weight Rating)
The GAWR is the maximum gross axle weight
rating. The actual load on an axle must never
exceed the gross axle weight rating. The
gross axle weight rating can be found on the
vehicle identification plate on the B-pillar on
the driver's side.
Speed index
The speed index is part of the tire
identification. Specifies the speed range for
which the tire is approved.
GTW (Gross Trailer Weight)
The GTW is the weight of a trailer including
the weight of the load, luggage, accessories
etc. on the trailer.
GVW (Gross Vehicle Weight)
The gross vehicle weight includes the weight
of the vehicle including fuel, tools, the spare
wheel, accessories installed, occupants,
luggage and the drawbar noseweight if
applicable. The gross vehicle weight must not
exceed the gross vehicle weight rating GVWR
as specified on the vehicle identification plate
on the B-pillar on the driver's side.
GVWR (Gross Vehicle Weight Rating)
The GVWR is the maximum permissible gross
weight of a fully loaded vehicle (the weight of
the vehicle including all accessories,
occupants, fuel, luggage and the drawbar
noseweight if applicable). The gross vehicle
weight rating is specified on the vehicle
identification plate on the B-pillar on the
driver's side.
Maximum weight of the laden vehicle
The maximum weight is the sum of the
unladen weight of the vehicle, the weight of
the accessories, the maximum load and the
weight of the optional equipment installed at
the factory.
Kilopascal (kPa)
Metric unit for tire pressure. 6.9 kPa is the
equivalent of 1 psi. Another unit for tire
pressure is bar. 100 kilopascal (kPa) is the
equivalent of 1 bar.
Load index
In addition to the load bearing index, the load
index may also be imprinted on the sidewall
of the tire. This specifies the load bearing
capacity more precisely.
Unladen weight
The weight of a vehicle with standard
equipment including the maximum capacity
of fuel, oil and coolant. It also includes the air-
conditioning system and optional equipment
if these are installed on the vehicle, but does
not include passengers or luggage.
Maximum tire load
The maximum tire load in kilograms or
pounds is the maximum weight for which a
tire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for one
tire.
Definitions for tires and loading285Tires and wheelsBA 204.9 USA, CA Edition A 2011; 1; 6, en-USd2mwentsVersion: 3.0.3.62010-06-15T08:58:39+02:00 - Seite 285Z
Tires of the same dimensions
i BA: both axlesModelGLK 350 34
GLK 350 4MATICR17BAAlloy wheels
Offset7.5 J x 17 H2
1.87 in (47.5 mm)Winter tires 35235/60 R17 102 H M+S
iR19BAAlloy wheels
Offset7.5 J x 19 H2
1.85 in (47 mm)All-weather tires235/50 R19 99 H M+SR20BAAlloy wheels
Offset8.5 J x 20 H2
1.77 in (45 mm)All-weather tires235/45 R20 100 H XL M+S
Spare wheel
i Please note that the tire pressure of the spare wheel differs from the tire pressure of the
other wheels.
i The specified tire pressure is printed in yellow on the emergency spare wheel.
Collapsible emergency spare wheel 36All modelsR17Alloy wheels
Offset6 B x 17 H2
0.98 in (25 mm) Tires185/75-17 98 PTire pressure280 kPa (2.8 bar/41 psi)34 USA only.
35 Not available as standard or optional equipment from the factory.
36 Use of snow chains not permitted.Wheel/tire combinations289Tires and wheelsBA 204.9 USA, CA Edition A 2011; 1; 6, en-USd2mwentsVersion: 3.0.3.62010-06-15T08:58:39+02:00 - Seite 289Z