Always observe the maximum permissible
speed specified for the M+S tires you have
mounted.
Once the winter tires are mounted:
X
Check the tire pressures (Y page 369).
X Vehicles for Canada: restart the tire
pressure loss warning system
(Y page 370).
X Restart the tire pressure monitor
(Y page 370).
For more information on driving with the
emergency spare wheel, see (Y page 398). Snow chains
G
WARNING
If snow chains are installed to the front
wheels, they may drag against the vehicle
body or chassis components. This could
cause damage to the vehicle or the tires.
There is a risk of an accident.
To avoid hazardous situations:
R never install snow chains to the front
wheels
R always install snow chains in pairs to the
rear wheels.
! On vehicles with AIRMATIC, you must
drive at raised vehicle level if snow chains
have been mounted. The vehicle may
otherwise be damaged.
! On some tire sizes there is not enough
space
for snow chains. To avoid damage to
the vehicle or tires, observe the "Wheel and
tire combinations" section under "Tires and
wheels".
! Vehicles with steel wheels: if you wish
to mount snow chains on steel wheels,
make sure that you remove the respective
wheels' hubcaps first. The hubcaps may
otherwise be damaged.
For safety reasons, Mercedes-Benz
recommends that you only use snow chains
that have been specially approved for your vehicle by Mercedes-Benz, or are of a
corresponding standard of quality.
If you intend to mount snow chains, please
bear the following points in mind:
R
Snow chains may not be mounted on all
wheel/tire combinations. Permissible
wheel-tire combinations (Y page 389).
R Only use snow chains when driving on
roads completely covered by snow.
Remove the snow chains as soon as
possible when you come to a road that is
not snow-covered.
R Local regulations may restrict the use of
snow chains. Observe the appropriate
regulations if you wish to mount snow
chains.
R Do not exceed the maximum permissible
speed of 30 mph (50 km/h).
i You may wish to deactivate ESP ®
when
pulling away with snow chains installed
(Y page 70). This way you can allow the
wheels to spin in a controlled manner,
achieving an increased driving force
(cutting action).
For more information on driving with the
emergency spare wheel, see
(Y page 398). Winter operation
365
Wheels and tires Z
when adjusting the tire pressure
(Y page 366).
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 366).
Information on air pressure for the tires on
your vehicle can be found:
R
on the vehicle's Tire and Loading
Information placard on the B-pillar
(Y page 373)
R on the tire pressure label on the fuel filler
flap ( Y page 170)
R in the "Tire pressure" section
R under "Tire pressure"
(Y page 366)
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 366).
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,
check the tire pressure again using the tire
pressure gauge.
X Screw the valve cap onto the valve.
X Repeat these steps for the other tires. Tire pressure loss warning system
(Canada only)
Important safety 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 appear in the multifunction
display.
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 366).
The tire pressure loss warning system does
not replace the need to regularly check your
vehicle's tire pressures, since 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 to your vehicle's
tires.
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 driving with a heavy load (in the
vehicle or on the roof). Tire pressure
369
Wheels and tires Z
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 366).
X Make sure that the SmartKey is in
position 2 (Y
page 153) in the ignition lock.
X Press = or ; on the steering wheel
to select the Serv.Serv. menu.
X Press the 9 or : button to select
Tire Pressure.
X Press the a button.
The message appears in the multifunction
display.
If you wish to confirm the restart:
X Press the a button.
The Tire Pressure Now OK? message
appears in the multifunction display.
X Press the 9 or : button to select
Yes.
X Press 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:
X
Press the % button.
or
X When the Tire Pressure Now OK?
message appears, press the 9
or : button to select Cancel.
X Press the a button.
The tire pressure values stored at the last
restart will continue to be monitored. Tire pressure monitor
Important safety notes G
WARNING
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the pressure
recommended by the vehicle manufacturer
on the Tire and Loading Information placard
on the driver's door B-pillar or the tire
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 pressure label,
you should determine the proper tire 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 370
Tire pressure
Wheels and tires
reached the level to trigger illumination of the
TPMS low tire pressure telltale.
USA only:
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate if 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 warning lamp will
flash for approximately a minute and then
remain continuously illuminated. This
sequence will be repeated every time the
vehicle is started as long as the malfunction
exists.
When
the malfunction indicator is 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.
It is the driver's responsibility to set the tire
pressure to that recommended for cold tires
which is suitable for the operating situation
(Y page 366). Note that the correct tire
pressure for the current operating situation
must first be taught-in to the tire pressure
monitor. If there is a substantial loss of
pressure, the warning threshold for the
warning message is aligned to the reference
values taught-in. Restart the tire pressure
monitor after adjusting the pressure of the
cold tires (Y page 373). The current
pressures are saved as new reference values.
As a result, a warning message will appear if
the tire pressure drops significantly.
The tire pressure monitor does not warn you
of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
(Y page 366). 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.
If a tire pressure monitor system is installed,
the vehicle's wheels have sensors installed
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.
The tire pressure monitor has a yellow
warning lamp in the instrument cluster for
indicating pressure loss/malfunctions (USA)
or pressure loss (Canada). Whether the
warning lamp flashes or lights up indicates
whether a tire pressure is too low or the tire
pressure monitor is malfunctioning:
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 USA only: if the warning lamp flashes for
around a minute and then remains lit
constantly, the tire pressure monitor is
malfunctioning.
Information on tire pressures is displayed in
the multifunction display. After a few minutes
of driving, the current tire pressure of each
tire is shown in the multifunction display.
USA only: if there is a malfunction with the
tire pressure monitor it can take more than
ten minutes until the malfunction is shown by
the tire pressure warning lamp flashing for
approximately one minute and then lighting
up continuously. When the malfunction has
been rectified, the tire pressure warning lamp
goes out after a few minutes of driving.
The tire pressure values indicated by the on-
board computer may differ from those
measured at a gas station with a pressure
gauge. The tire pressures shown by the on-
board computer refer to those measured at
sea level. At high altitudes, the tire pressure Tire pressure
371
Wheels and tires Z
minutes of driving, and the tire pressures
are displayed for the correct positions.
Restarting the tire pressure monitor 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. In most
cases, the tire pressure monitor will
automatically detect the new reference
values after you have changed the tire
pressure. However, you can also define
reference values manually as described here.
The tire pressure monitor then monitors the
new tire pressure values.
X Set the tire pressure to the value
recommended for the corresponding
driving situation on the Tire and Loading
Information placard on the driver's side
B-pillar ( Y page 366).
Additional
tire pressure values for different
loads can also be found on the tire pressure
table on the inside of the fuel filler flap
(Y page 366).
X Make sure that the tire pressure is correct
on all four wheels.
X Make sure that the SmartKey is in position
2 in the ignition lock.
X Press the = or ; button on the
steering wheel to select the Serv. menu.
X Press the 9 or : button to select
Tire Pressure.
X Press the a button.
The multifunction display shows the
current tire pressure for each tire or the
Tire pressures displayed after
driving a few minutes message.
X Press the : button.
The multifunction display shows the Use
Current Pressure Values as New
Reference Values message. If you wish to confirm the restart:
X
Press the a button.
The Tire Pressure 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 tire
pressures are then accepted as reference
values and monitored.
If you wish to cancel the restart:
X Press the % button.
The tire pressure values stored at the last
restart will continue to be monitored. Loading the vehicle
Instruction labels for tires and loads
G
WARNING
Overloaded tires can overheat, causing a
blowout.
Overloaded tires can also impair the
steering and driving characteristics and lead
to brake failure. There is a risk of accident.
Observe the load rating of the tires. The load
rating must be at least half of the GAWR of
your vehicle. Never overload the tires by
exceeding the maximum load.
Two instruction labels on your vehicle show
the maximum possible load.
(1) The Tire and Loading Information placard is
on the B-pillar on the driver's side. The
Tire and Loading Information placard
shows the maximum permissible number
of occupants and the maximum
permissible vehicle load. It also contains
details of the tire sizes and
corresponding pressures for tires
installed at the factory.
(2) The vehicle identification plate is on the B-pillar on the driver's side. The vehicle
identification plate informs you of the
gross
vehicle weight rating. It is made up
of the vehicle weight, all vehicle Loading the vehicle
373
Wheels and tires Z
To ensure that your vehicle does not exceed
the maximum permissible values (gross
vehicle weight and maximum gross axle
weight rating), have your loaded vehicle
(including driver, occupants, cargo, and full
trailer load if applicable) weighed on a
suitable vehicle weighbridge.
All about wheels and tires
Uniform Tire Quality Grading
Standards
Overview of Tire Quality Grading
Standards 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
grade, ; traction grade and = temperature
grade. These regulations do not apply to
Canada. Nevertheless, all tires sold in North
America are provided with the corresponding
quality grading markings on the sidewall of
the tire.
Where applicable, the tire grading
information can be found on the tire sidewall
between the tread shoulder and maximum
tire width.
Example:
R Treadwear grade: 200
R Traction grade: AA
R Temperature grade: A All passenger car tires must conform to the
statutory safety requirements in addition to
these grades.
i
The actual values for tires are vehicle-
specific
and may deviate from the values in
the illustration.
Treadwear The treadwear grade is a comparative rating
based
on the wear rate of the tire when tested
under controlled conditions on a specified
U.S. government course. For example, a tire
graded 150 would wear one and one-half
times as well on the government course as a
tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm, due to variations in driving habits,
service practices and differences in road
characteristics and climate conditions.
Traction G
WARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
! Avoid
wheelspin. This can lead to damage
to the drive train.
The traction grades, from highest to lowest,
are AA, A, B, and C. Those grades represent
the tire's ability to stop on a wet surface as
measured under controlled conditions on
specified government test surfaces of asphalt
and concrete. A tire marked C may have poor
traction performance.
The safe speed on a wet, snow covered or icy
road is always lower than on dry road
surfaces.
You should pay special attention to road
conditions when temperatures are around
freezing point. All about wheels and tires
377Wheels and tires Z
Mercedes-Benz recommends a minimum
tread
depth of ã in (4 mm) on all four winter
tires. Observe the legally required minimum
tire tread depth (Y page 363). Winter tires can
reduce the braking distance on snow-covered
surfaces in comparison with summer tires.
The braking distance is still much further than
on surfaces that are not icy or covered with
snow. Take appropriate care when driving.
Further information on winter tires (M+S
tires) (Y page 364).
Temperature G
WARNING
The temperature grade for this tire is
established for a tire that is properly inflated
and not overloaded. Excessive speed,
underinflation, or excessive loading, either
separately or in combination, can cause
excessive heat build-up and possible tire
failure.
The temperature grades are A (the highest),
B, and C. These represent the tire's
resistance to the generation of heat and its
ability to dissipate heat when tested under
controlled conditions on a specified indoor
laboratory test wheel. Sustained high
temperature
can cause the material of the tire
to degenerate and reduce tire life, and
excessive temperature can lead to sudden
tire failure. The grade C corresponds to a level
of performance which all passenger car tires
must meet under the 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. Tire labeling
Overview :
Uniform Tire Quality Grading Standard
(Y page 382)
; DOT, Tire Identification Number
(Y page 381)
= Maximum tire load ( Y page 381)
? Maximum tire pressure (Y page 368)
A Manufacturer
B Tire material ( Y page 382)
C Tire size designation, load-bearing
capacity and speed index
(Y page 378)
D Load index ( Y page 381)
E Tire name
The markings described above are on the tire
in addition to the tire name (sales
designation) and the manufacturer's name.
i Tire data is vehicle-specific and may
deviate from the data in the example.
Tire size designation, load-bearing
capacity and speed rating G
WARNING
Exceeding the stated tire load-bearing
capacity and the approved maximum speed
could
lead to tire damage or the tire bursting.
There is a risk of accident. 378
All about wheels and tires
Wheels and tires
Index Speed rating
S up to 112 mph (180 km/h)
T up to 118mph (190 km/h)
H up to 130mph (210 km/h)
V up to 149 mph (240 km/h)
W up to 168 mph (270 km/h)
Y up to 186mph (300 km/h)
ZR...Y up to 186mph (300 km/h)
ZR...(..Y) over 186 mph (300 km/h)
ZR over 149 mph (240 km/h)
R
Optionally, tires with a maximum speed of
over
149 mph (240 km/h) may have a “ZR”
in the size description, depending on the
manufacturer (e.g. 245/40 ZR18).
The service specification is made up of
load-bearing index A and speed rating
B.
R If the size description of your tire includes
"ZR" and there are no service
specifications, ask the tire manufacturer in
order to find out the maximum speed.
If a service specification is available, the
maximum speed is limited according to the
speed rating in the service specification.
Example: 245/40 ZR 18 97 Y. In this
example, "97 Y" is the service specification.
The letter "Y" represents the speed rating
and the maximum speed of the tire is
limited to 186 mph (300km/h).
R Every tire that has a maximum speed of
more than 186 mph (300 km/h) must have
a "ZR" in the size description and the
service specification must be given in
parentheses. Example:
275/40 ZR 18 (99 Y). The speed rating "(Y)"
indicates that the maximum speed of the
tire is over 186 mph (300 km/h). Ask the tire manufacturer about the maximum
speed.
All-weather tires and winter tires Index Speed rating
Q M+S
4 up to 100 mph (160 km/h)
T M+S
4 up to 118mph (190 km/h)
H M+S
4 up to 130mph (210 km/h)
V M+S
4 up to 149 mph (240 km/h)
i
Not
all tires with the M+S marking provide
the driving characteristics of winter tires.
In addition to the M+S marking, winter tires
also have the i snowflake symbol on
the tire wall. Tires with this marking fulfill
the requirements of the Rubber
Manufacturers Association (RMA) and the
Rubber Association of Canada (RAC)
regarding the tire traction on snow. They
have been especially developed for driving
on snow.
An electronic speed limiter prevents your
vehicle from exceeding the following speeds:
R all vehicles (except AMG vehicles):
130 mph (210 km/h)
R AMG vehicles: 155 mph (250 km/h)
R AMG vehicles with Performance Package
(Wagon): 174 mph (280 km/h)
R AMG vehicles with Performance Package
(Sedan): 186 mph (300 km/h)
The speed rating of tires mounted at the
factory may be higher than the maximum
speed that the electronic speed limiter
permits.
Make sure that your tires have the required
speed rating, e.g. when buying new tires. The
required speed rating for your vehicle can be
found in the "Tires" section ( Y page 389).
Further information about reading tire data
can be obtained from any qualified specialist
workshop.
4 Or M+S i for winter tires.380
All about wheels and tires
Wheels and tires