
Never exceed the maximum permissible tire
inflation pressure. Always observe the
recommended tire pressure for yourv
ehicle
when adjusting the tire pressure
(Y page 404).
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration. Checking the tire pressures
Important safety notes Observe the notes on tire pressure
(Y
page 404).
Information on air pressure for the tires on
your vehicle can be found:
R on the vehicle's Tire and Loading
Information placard loading information
table on the B-pillar (Y page 412)
R on the tire pressure label on the fuel filler
flap
R in the "Tire pressure" section
R under "Tire pressure" (Y page 404)
Checking tire pressures manually To determine and set the correct tire
pressure, proceed as follows:
X Remove the valve cap of the tire that is to
be checked.
X Press the tire pressure gauge securely onto
the valve.
X Read the tire pressure and compare it with
the recommended value on the Tire and
Loading Information placard (Y page 404).
X If the tire pressure is too low, increase it to
the recommended value.
X If the tire pressure is too high, release air
by pressing down the metal pin in the valve.
Use the tip of a pen, for example. Then,
chec kthe tire pressure again using the tire
pressure gauge.
X Screw the valve cap onto the valve.
X Repeatt hese steps for the other tires. Tire pressure loss warning system
(Canada only)
General notes While the vehicle is in motion, the tire
pressure loss warning system monitors the
set tire pressure using the rotational speed of
the wheels. This enables the system to detect
significant pressure loss in a tire. If the speed
of rotation of a wheel changes as a result of
a loss of pressure, a corresponding warning
message will appearint
he multifunction
display.
You can recognize the tire pressure loss
warning by the Run Flat Indicator Active Press 'OK' to Restart message
which appears in the Serv. menu of the
multifunction display. Information on the
message display can be found under
"Restarting the tire pressure loss warning
system" (Y page 408).
Important safety notes The tire pressure warning system does not
warn you of an incorrectly set tire pressure.
Observe the notes on the recommended tire
pressure (Y
page 404).
The tire pressure loss warning does not
replace the need to regularly check the tire
pressure. An even loss of pressure on several
tires at the same time cannot be detected by
the tire pressure loss warning system.
The tire pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the
tire is penetrated by a foreign object. In the
event of a sudden loss of pressure, bring the
vehicle to a halt by braking carefully. Avoid
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's
tires.
R road conditions are wintry.
R you are driving on sand or gravel. Check
407Wheels and tires Z

R
you adop tavery 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 load (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
X Before restarting, make sure that the tire
pressures are set properly on all four tires
for the respective operating conditions.
The recommended tire pressures can be
found on the Tire and Loading Information
placard on the B-pillar on the driver's side
or the tire pressure table on the fuel filler
flap.
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.
X Also observe the notes in the section on tire
pressures (Y page 404).
X Make sure that the SmartKey is in position
2 in the ignitio nlock (Y page 163).
X Press the 0002or0005 button on the
steering wheel to select the Serv. menu.
X Press the 0003or0004 button to select
Tire Pressure .
X Press the 000Bbutton.
The Run Flat Indicator active Restart with OK message appears in the
multifunction display. If you wish to confirm the restart:
X
Press the 000Bbutton.
The Tire Pressure Now OK? message
appears in the multifunction display.
X Press the 0003or0004 button to select
Yes .
X Press the 000Bbutton.
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:
X Press the 0007button.
or
X If the Tire Pressure Now OK? message
appears, use the 0003or0004 button to
select Cancel .
X Press the 000Bbutton.
The tire pressure values stored at the last
restart will continue to be monitored. Tire pressure monitor
General notes If a tire pressure monitor is installed, the
vehicle's wheels have sensors that monitor
the tire pressures in all four tires. The tire
pressure monitor warns you if the pressure
drops in one or more of the tires. The tire
pressure monitor only functions if the correct
sensors are installed on all wheels.
Information on tire pressures is displayed in
the multifunction display .After a few minutes
of driving, the current tire pressure of each
tire is show nintheServ. menu of the
multifunction display. For further information
on displaying this message, refer to the
"Checking the tire pressure electronically"
section (Y page 410). 408
CheckWheels and tires

Traction
Traction is the result of friction between the
tires and the road surface.
TWR (Tongue Weight Rating)
The TWR specifies the maximu mpermissible
weight that the ball coupling of the trailer tow
hitch can support.
Treadwear indicators
Narrow bars (tread wear bars) that are
distributed over the tire tread. If the tire tread
is level with the bars, the wear limit of 0007in
(1.6 mm) has been reached.
Occupant distribution
The distribution of occupants in a vehicle at
their designated seating positions.
Total load limit
Rated cargo and luggage load plus
68 kilograms (150 lb) multiplied by the
number of seats in the vehicle. Changing
awheel Flat tire
You can find information on wha tto do in the
event of a flat tire in the "Breakdown
assistance" section (Y page 383).
Information on driving with MOExtended tires
in the event of a flat tire can be found under
"MOExtended tires (tires with run-flat
characteristics" (Y page 384).
The "Breakdown assistance" section
(Y page 383) contains information and notes
on how to deal with a flat tire. Information on
driving with MOExtended tires in the event of
a flat tire can be found under "MOExtended
tires (tires with run-flat characteristics"
(Y page 384).
Vehicles with an emergency spare
wheel: in the event of a flat tire, mount the
emergency spare wheel according to the
description under "Mounting a wheel"
(Y page 424). Rotating the wheels
G
WARNING
Interchanging the front and rear wheels may
severely impair the driving characteristics if
the wheels or tires have different dimensions.
The wheel brakes or suspension components
may also be damaged. There is a risk of
accident.
Rotate front and rear wheels only if the wheels
and tires are of the same dimensions.
! On vehicles equipped with a tire pressure
monitor, electronic components are
located in the wheel.
Tire-mounting tools should not be used
near the valve. This could damage the
electronic components.
Only have tires changed at a qualified
specialist workshop.
Always observe the instructions and safety
notes in the "Mounting awheel" section
(Y page 424).
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 this is not
available, the tires should then be rotated
every 3000 to 6000 miles (5000 to
10,000 km), or earlier if the tire wear requires
this. Do not change the direction of wheel
rotation.
Cleant he contact surfaces of the wheel and
the brake disc thoroughly every time a wheel
is interchanged. Check the tire pressure and,
if necessary, restart the tire pressure loss
warning system or the tire pressure monitor. Changing
awheel
423Wheels and tires Z

These tires have been specially adapted for
use with the control systems, such as ABS
or ESP ®
, and are marked as follows:
R MO =Mercedes-Benz Original
R MOE =Mercedes-Benz Original Extended
(tires featuring run-flat characteristics)
R MO1 =Mercedes-BenzO riginal (only
certain AMG tires)
Mercedes-Benz Original Extended tires
may only be used on wheels that have been
specifically approved by Mercedes-Benz.
Only use tires, wheels or accessories
tested and approved by Mercedes-Benz.
Certain characteristics, e.g. handling,
vehicle noise emissions or fuel
consumption, may otherwise be adversely
affected. In addition, when driving with a
load, tire dimension variations could cause
the tires to come into contact with the
bodywork and axle components. This could
result in damage to the tires or the vehicle.
Mercedes-Benz accepts no liability for
damage resulting from the use of tires,
wheels or accessories other than those
tested and approved.
Information on tires, wheels and approved
combinations can be obtained from any
qualified specialist workshop.
! Retreaded tires are neither tested nor
recommended by Mercedes-Benz, since
previous damage cannot always be
detected on retreaded tires. As a result,
Mercedes-Benz cannot guarantee vehicle
safety if retreaded tires are mounted. Do
not mount used tires if you have no
information about their previous usage.
Overview of abbreviations usedint he
following tire tables:
R BA: both axles
R FA: front axle
R RA: rear axle The recommended pressures for various
operating conditions can be found:
R
on the Tire and Loading Information placard
with the recommended tire pressures on
the B-pillar on the driver's side
R in the tire pressure table on the inside of
the fuel filler flap
Observe the notes on recommended tire
pressures under various operating conditions
(Y page 404).
Check tire pressures regularly, and only when
the tires are cold. Comply with the
maintenance recommendations of the tire
manufacturer in the vehicle document wallet.
Notes on the vehicle equipment –always
equip the vehicle with:
R tires of the same size on a given axle (left/
right)
R the same type of tires at a given time
(summer tires, winter tires, MOExtended
tires)
Vehicles with MOExtended tires are not
equipped with a TIREFIT kit at the factory. It
is therefore recommended that you
additionally equip your vehicle with a TIREFIT
kit if you moun ttires that do not feature run-
flat properties, e.g. winter tires. ATIREFIT kit
may be obtained from a qualified specialist
workshop.
i Not all wheel and tire combinations are
available at the factory for all countries.
i On the following pages, you can find
information on approved wheelr ims and
tire sizes for equipping your vehicle with
winter tires. Winter tires are not available
at the factory as standard equipmen tor
optional extras.
If you would like to equip your vehicle with
approved winter tires, you may also, in
certain circumstances, require rims of the
appropriate size. The sizes of the approved
winter tires may deviate from that of the
standard tires. This is dependent on the
model and the equipment installed at the
factory. Wheel and tire combinations
429Wheels and tires Z

GL 550 4MATIC BlueEFFICIENCY
All-weather tires
R 19
Tires Alloy wheels
BA: 275/50 R 19 111 H M+S
3 BA: 8.5 J x 19 H2
Wheel offset: 2.44 in (62 mm)
R 20
Tires Alloy wheels
BA: 275/50 R 20 109 H M+S
3 BA: 8.5 J x 20 H2
Wheel offset: 2.44 in (62 mm)
BA: 275/50 R 20 109 H M+SMOExtended
3, 4 BA: 8.5 J x 20 H2
Wheel offset: 2.44 in (62 mm)
R 21
Tires Alloy wheels
BA: 295/40 R 21 111 V XL M+S
3 BA: 10.0 J x 21 H2
Wheel offset: 1.81 in (46 mm)
All-terrain tires
R 19
Tires Alloy wheels
BA: 275/55 R 19 111 H M+S
3 BA: 8.5 J x 19 H2
Wheel offset: 2.44 in (62 mm)
Winter tires
R 19
Tires Alloy wheels
BA: 265/55 R 19 109 H M+S
0002 BA: 8.5 J x 19 H2
Wheel offset: 2.44 in (62 mm)
3
Use of snow chains not permitted. Observe the notes under "Snow chains".
4 MOExtended tires (tires featuring run-flat characteristics) only in combinatio nwith an activated tire pressure
loss warning syste mortire pressure monitor. Wheel and tire combinations
433Wheels and tires Z