2010 MERCEDES-BENZ GL550 steering

Checking tire inflation pressure
Safety notesGWarning!
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
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.
Check the tire inflation pressure at least once
a month.
Check and adjust the tire inflation pressure
when the tires are cold ( Y page 234).
Checking tire inflation pressure
manually
Follow the steps below to achieve correct tire
inflation pressure:
XRemove the cap from the valve on one tire.XFirmly press a tire gauge onto the valve.XRead the tire inflation pressure on the tire
gauge and check against the
recommended tire inflation pressure on the
Tire and Loading Information placard on the
driver’s door B-pillar ( Y page 242). If
necessary, add air to achieve the
recommended tire inflation pressure.XIf you have overfilled the tire, release tire
inflation pressure by pushing the metalstem of the valve with e.g. a tip of a pen.
Then recheck the tire inflation pressure
with the tire gauge.XInstall the valve cap.XRepeat this procedure for each tire.
Tire pressure loss warning system
(Canada only)
While the vehicle is being driven, the tire
pressure loss warning system monitors the
set tire inflation pressures by evaluating each
wheel’s rotational speed. This allows the
system to detect a significant loss of pressure
in a tire. If a wheel’s rotational speed changes
due to falling tire inflation pressure, you will
see a corresponding warning message in the
multifunction display.
The tire pressure loss warning system may
function in a restricted manner or with a delay
R when snow chains are mounted to the
vehicle
R in the presence of ice and snow
R when you are driving on a loose surface
(e.g. sand or gravel)
R when you are driving in a very sporty
manner (involving rapid acceleration or
high speeds in curves)
GWarning!
When the multifunction display shows the
message Tire Pressure Check Tires , one
or more of your tires are significantly
underinflated. You should stop and check
your tires as soon as possible, and inflate
them to the proper tire inflation pressure as
indicated on the vehicle’s Tire and Loading
Information placard or on the tire inflation
pressure label.
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.
Tires and wheels237OperationX164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 237Z

Each tire, including the spare, should be
checked at least once a month when cold.
Inflate the tires to the recommended tire
inflation pressure as specified on
R the Tire and Loading Information placard on
the driver’s door B-pillar
or
R the tire inflation pressure label located on
the inside of the fuel filler flap
i The recommended tire inflation pressures
for your vehicle can be found on
R the Tire and Loading Information placard
located on the driver’s door B-pillar
( Y page 242)
R the tire inflation pressure label on the
inside of the fuel filler flap
The tire inflation pressures are not listed in
the Operator’s Manual.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.
Restarting the tire pressure loss warning
system
The tire pressure loss warning system must
be restarted in the following situations:
R after you have changed the tire inflation
pressure
R after you have replaced the wheels or tires
R after you have installed new wheels or tiresXUsing the Tire and Loading Information
placard on the driver’s door B-pillar or, if
available, the tire inflation pressure label on
the inside of the fuel filler flap, make sure
the tire inflation pressure of all four tires is
correct.GWarning!
The tire pressure loss warning system can
only warn you in a reliable manner if you have
set the correct tire inflation pressures for
each tire.
If an incorrect tire inflation pressure was set,
the system will monitor the pressure
according to the incorrect value.
XSwitch on the ignition.XMake sure the standard display appears in
the multifunction display ( Y page 128).XPress button * or & on the
multifunction steering wheel repeatedly
until the following message appears in the
multifunction display:
Run Flat Indicator
Active
Menu: R-ButtonXPress the reset button ( Y page 124).
The following message will appear in the
multifunction display:
Restart
Run Flat Indicator?XIf you wish to confirm: Press button
W .
The following message will appear in the
multifunction display:
Run Flat Indicator
Restarted238Tires and wheelsOperation
X164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 238

After a certain “learning phase”, the tire
pressure loss warning system checks the
set pressure values for all four tires.XIf you wish to cancel: Press button X.
Advanced Tire Pressure Monitoring
System (Advanced TPMS), (USA only)
Your vehicle is equipped with the Advanced
Tire Pressure Monitoring System (Advanced
TPMS). It measures the tire inflation pressure
in the vehicle’s tires and issues warnings in
case of pressure loss in one or more of the
tires.
The TPMS is equipped with a combination low
tire pressure/ TPMS malfunction telltale in
the instrument cluster. Depending on how the
telltale illuminates, it indicates a low tire
pressure condition or a malfunction in the
TPMS system itself:
R If the telltale illuminates continuously, one
or more of your tires is significantly
underinflated. There is no malfunction in
the TPMS.
R If the telltale flashes for 60 seconds and
then stays illuminated, the TPMS system
itself is not operating properly.
The TPMS only functions on wheels that are
equipped with the proper electronic sensors.
GWarning!
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust tire inflation pressure according to the
Tire and Loading Information placard or the
supplemental tire inflation pressure
information on the inside of the fuel filler flap.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of 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.
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 placard on the driver’s door B-
pillar or the tire inflation pressure label 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 placard
or the tire inflation pressure label, 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 monitoring
system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires are significantly underinflated.
Accordingly, when the low tire pressure
telltale illuminates, 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
responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level to trigger illumination of the
TPMS low tire pressure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined with
the low tire pressure telltale. When the
system detects a malfunction, the telltale will
flash for approximately 1 minute and then
remain continuously illuminated. This
sequence will continue upon subsequent
vehicle start-ups as long as the malfunction
exists. When the malfunction indicator is
Tires and wheels239OperationX164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 239Z

illuminated, the system may not be able to
detect or signal low tire pressure as intended.
TPMS malfunctions may occur for a variety of
reasons, including the installation of
incompatible replacement or alternate tires
or wheels on the vehicle that prevent the
TPMS from functioning properly. Always
check the TPMS malfunction telltale after
replacing one or more tires or wheels on your
vehicle to ensure that the replacement or
alternate tires and wheels allow the TPMS to
continue to function properly.
iIf a condition causing the TPMS to
malfunction develops, it may take up to
10 minutes for the system to signal a
malfunction using the TPMS telltale
flashing and illumination sequence.
The telltale extinguishes after a few
minutes driving if the malfunction has been
corrected.
Tire pressure inquiries are made using the
multifunction display. The current tire
inflation pressure for each tire appears in the
multifunction display after a few minutes of
driving.
iPossible differences between the
readings of a tire pressure gauge of an air
hose, e.g. gas station equipment, and the
vehicle’s control system can occur. The tire
pressure displayed by the control system
apply to sea level. In high-altitude
locations, the reading on a tire pressure
gauge will be higher than the reading issued
by the vehicle’s control system. Do not
reduce the tire inflation pressure under
such circumstances.
XSwitch on the ignition.XPress button V or U on the
multifunction steering wheel repeatedly
until the standard display appears in the
multifunction display (Y page 128).
XPress button & or * until the current
inflation pressure for each tire appears in
the multifunction display.
Example illustration
When the vehicle has been parked for longer
than 20 minutes, the message Tire
pressure displayed after driving
for a few minutes. appears in the
multifunction display.
The TPMS recognizes new wheels or sensors
automatically after the learn-in phase. As long
as the tire inflation pressure values cannot be
allocated to the individual wheels, the
message Tire Pressure Monitor Active
appears. Despite this message, the tire
inflation pressure values are monitored
already.
iWith a spare wheel mounted, the system
may still indicate the tire inflation pressure
of the removed road wheel for some
minutes. If this happens, keep in mind that
the indicated value where the spare wheel
is mounted does not reflect the actual
spare tire inflation pressure.
iOperating radio transmission equipment
(e.g. wireless headsets, two-way radios) in
or near the vehicle could cause the TPMS
to malfunction.
iThis device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful
interference, and
2. this device must accept any
interference received, including
interference that may cause undesired.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
240Tires and wheelsOperation
X164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 240

Tire inflation pressure warnings
If the system detects a significant loss of tire
inflation pressure in one or more than one
tire, a message appears in the multifunction
display. In addition, an acoustic warning
sounds and the low tire pressure telltale in the
instrument cluster comes on.
Example illustration
The respective tire is indicated by a red
rectangle.
Restarting Advanced TPMS
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 TPMS, the system sets
new reference values for each tire.
The TPMS must be restarted when you have
adjusted the tire inflation pressure to a new
level (e.g. because of different load or driving
conditions). The TPMS is then recalibrated to
the current tire inflation pressures.
Restart the TPMS after adjusting the tire
inflation pressure to the inflation pressure
recommended for the vehicle operating
condition. Tire pressure should only be
adjusted on cold tires. Observe the
recommended tire inflation pressure on the
Tire and Loading Information placard on the
driver’s door B-pillar. Some vehicles may have
supplemental tire pressure information for
driving at high speeds or for vehicle loads less
than the maximum loaded vehicle condition.
If such information is provided, it can be
found on the inside of the fuel filler flap.
XUsing the Tire and Loading Information
placard on the driver’s door B-pillar
(Y page 242) or the supplemental tire
inflation pressure information on the inside
of the fuel filler flap, make sure the tire
inflation pressure of all four tires is correct.
XSwitch on the ignition.XPress button V or U on the
multifunction steering wheel repeatedly
until the standard display appears in the
multifunction display (Y page 128).
XPress button & or * repeatedly until
you see the current inflation pressures for
each tire appear in the display or the
following message appears in the
multifunction display:
Tire pressure
displayed after
driving for
a few minutes.
XPress the reset button (Y page 124).
The following message will appear in the
multifunction display:
Restart tire
pressure monitor?
XIf you wish to confirm: Press button
W.
The following message will appear in the
multifunction display:
Tire Pressure Monitor
Restarted
After driving a few minutes the system
verifies that the current tire inflation
pressures are within the system’s specified
range. Afterwards the current tire inflation
pressures are accepted as reference values
and then monitored.
XIf you wish to cancel: Press button X.
iWhen the wheel positions have been
changed, the inflation pressure of a tire
may be displayed for the wrong position
temporarily. After driving for a few minutes,
the inflation pressure will be shown for the
correct position.
Tires and wheels241OperationX164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 241Z

Loading Information placard with regards to
loading your vehicle.
Tire and Loading Information
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.
Tire and Loading Information placard
iData shown on Tire and Loading
Information placard example are for
illustration purposes only. Load limit data
are specific to each vehicle and may vary
from data shown in the following
illustration. Refer to Tire and Loading
Information placard on vehicle for actual
data specific to your vehicle.
The Tire and Loading Information placard
showing load limit information : is located
on the driver’s door B-pillar (Y page 242).
XLocate the statement “The combined
weight of occupants and cargo should
never exceed XXX kilograms or XXX lbs.”
on the Tire and Loading Information
placard.
The combined weight of all occupants,
cargo/luggage and trailer tongue load (if
applicable) should never exceed the weight
referenced in that statement.
Seating capacity
iData shown on Tire and Loading
Information placard example are for
illustration purposes only. Seating capacity
data are specific to each vehicle and may
vary from data shown in the following
illustration. Refer to Tire and Loading
Information placard on vehicle for actual
data specific to your vehicle.
The seating capacity gives you important
information on the number of occupants that
can be in the vehicle. Observe front and rear
seating capacity. The Tire and Loading
Information placard showing seating
capacity : is located on the driver’s door
B-pillar (Y page 242).
Steps for determining correct load limit
The following steps have been developed as
required of all manufacturers under Title 49,
Code of U.S. Federal Regulations, Part 575
pursuant to the “National Traffic and Motor
Vehicle Safety Act of 1966”.
XStep 1: Locate the statement “The
combined weight of occupants and cargo
should never exceed XXX kg or XXX lbs.”
on your vehicle’s Tire and Loading
Information placard.
XStep 2: Determine the combined weight of
the driver and passengers that will be riding
in your vehicle.
Tires and wheels243OperationX164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 243Z

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 360).
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 between 8% and 15% 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 251).
For information on calculating total and cargo
load capacities, see (Y page 243).
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.
MOExtended system
The MOExtended system allows you to
continue driving your vehicle even if there is
a total loss of pressure in one or more tires.
246Tires and wheelsOperation
X164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 246

Tire size designation, load and speed
rating:Tire width;Aspect ratio in %=Radial tire code?Rim diameterALoad index BSpeed symbol
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
General: Depending on the design standards
used, the tire size molded into the sidewall
may have no letter or a letter preceding the
tire size designation.
No letter preceding the size designation (as
illustrated above): Passenger car tire based
on European design standards.
Letter “P” preceding the size designation:
Passenger car tire based on U.S. design
standards.
Letter “LT” preceding the size designation:
Light Truck tire based on U.S. design
standards.
Letter “T” preceding the size designation:
Temporary spare tires which are high
pressure compact spares designed for
temporary emergency use only.
Tire width
Tire width : indicates the nominal tire width
in millimeters.
Aspect ratio
Aspect ratio ; is the dimensional
relationship between tire section height and
section width and is expressed in percentage.
The aspect ratio is arrived at by dividing
section height by section width.
Tire code
Tire code = indicates the tire construction
type. The “R” stands for radial tire type. Letter
“D” means diagonal or bias ply construction;
letter “B” means belted-bias ply construction.
At 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 ZR 18). For
additional information, see “Tire speed
rating” (Y page 252).
Rim diameter
Rim diameter ? is the diameter of the bead
seat, not the diameter of the rim edge. The
rim diameter is indicated in inches (in).
Load index
GWarning!
The tire load rating must always be at least
half of the GAWR of your vehicle. Otherwise,
tire failure may be the result which may cause
an accident and/or serious injury to you or
others.
Always replace rims and tires with the same
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.
Load index A is a numerical code associated
with the maximum load a tire can support.
Tires and wheels251OperationX164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 251Z