Rcheck the tire for foreign bodies.
R check whether the wheel is losing air or the
valve is leaking.
R make sure that only a valve cap approved
by Mercedes-Benz is installed on the tire
valve.
Tire pressures that are too low have a
negative effect on vehicle safety, which could
lead you to cause an accident.
Only correct tire pressures when the tires are
cold. The tires are cold when the vehicle has
been parked for at least three hours or driven
for less than 1 mile (1.6 km). The tire
temperature changes depending on the
outside temperature, the vehicle speed and
the tire load. If the tire temperature changes
by 18 ‡ (10 †), the tire pressure changes by
approximately 10 kPa (0.1 bar/1.5 psi). Take
this into account when checking the pressure
of warm tires and only correct the tire
pressure if it is too low for the current
operating conditions. If you check the tire
pressure when the tires are warm, the reading
will be higher than if the tires were cold. This
is normal. Do not reduce the tire pressure to
the value specified for cold tires. The tire
pressure would otherwise be too low.
Observe the recommended tire pressure
specifications for cold tires on the Tire and
Loading Information placard on the B-pillar on
the driver's side.
i The specifications given on the following
Tire and Loading Information placard are
examples. Tire pressure specifications are
vehicle-specific and may deviate from the
data shown here. The tire pressure
specifications for your vehicle can be found
on the Tire and Loading Information placard
of your vehicle.
You will find recommended tire pressure
specifications : for cold tires and for a fully
loaded vehicle on the Tire and Loading
Information placard. The tire pressure
specifications apply to tires which are
installed at the factory.
Important notes on tire pressure
GWarning
If the tire 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.
The temperature and pressure of the tires
increase when the vehicle is in motion. This
is dependent on the driving speed and the
load.
If you wish to drive at high speeds of
100 mph (160 km/h) or higher when this is
allowed, use the tire pressure table on the
inside of the fuel filler flap to set the correct
tire pressures when the wheels are cold. If the
tire pressure is not set correctly, this can lead
to an excessive build up of heat and a sudden
loss of pressure.
For more information, contact a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center.
i Ride comfort may be affected if the tire
pressure is adjusted to the recommended
value for speeds of over
100 mph(160 km/h).
484Tire pressureTires and wheels
Make sure that the tire pressure for normal
speeds is adopted again.
Additional specifications of tire pressure
values for loads can also be found on the tire
pressure table on the inside of the fuel filler
flap.
The tire pressure for emergency spare wheels
can be found:
R on the yellow label on the wheel rim of the
emergency spare wheel
R in the "Wheel and tire combinations"
section ( Y page 503) of this Operator's
Manual
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
i The specifications shown in the examples
in the tire pressure tables are only
examples. Tire pressure specifications are
vehicle-specific and may deviate from the
data shown here. The tire pressure
specifications that are valid for your vehicle
can be found on your vehicle's tire pressure
table.
The tire pressures in the tire pressure table
on the inside of the fuel filler flap are valid for
all approved tires installed at the factory,
unless stated otherwise.
Tire pressure table for all approved tires installed
at the factory (example)
If the tire pressure precedes a tire size, the
tire pressure specification is only valid for this
tire size. The vehicle loading conditions
"partially laden" or "fully laden" are specified
using a differing number of persons and
luggage in the table. The actual number of
seats may differ from this.
Tire pressure table with tire sizes (example)
Some tire pressure tables only show the rim
diameter instead of the complete tire size,
e.g. R18 . The rim diameter is a component of
the tire size and can be read from the tire
sidewall ( Y page 496).
Tire pressure too low or too high
Underinflated tires
GWarning
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.
Underinflated tires can:
R wear excessively and/or unevenly
R adversely affect fuel economy
Tire pressure485Tires and wheelsZ
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 when
the tire pressure monitoring 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 one 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 lit, 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.
i USA only:
If the tire pressure monitor is
malfunctioning, it may take more than
10 minutes for the tire pressure warning
lamp to inform you of the malfunction by
flashing for 60 seconds and then remaining
lit.
When the malfunction has been rectified,
the tire pressure warning lamp goes out
after driving for a few minutes.
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.
i 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
values indicated by a pressure gauge are
higher than those shown by the on-board
computer. In this case, do not reduce the
tire pressures.
i The operation of the tire pressure monitor
can be affected by interference from radio
transmitting equipment (e.g. radio
headphones, two-way radios) that may be
operated in or near the vehicle.
i USA only:
This 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 withstand any
interference received, including
interference that may cause undesired
operation.
Unauthorized modifications to the device
could void the user’s authority to operate
the equipment.
i Canada only:
This device complies with the RSS-210
Rules from Industry Canada. 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 operation.
Unauthorized modifications to the device
could void the user’s authority to operate
the equipment.
Checking tire pressure electronicallyXMake sure that the SmartKey is in
position 2 ( Y page 299) in the ignition lock.XPress the = or ; button to select the
Service menu.488Tire pressureTires and wheels
Tread wear
The tread wear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified
U.S. government test track. For example, a
tire graded 150 would wear one and one-half
times as well on the government test track 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
GWarning
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.
The traction grades, from highest to lowest,
are AA, A, B, and C. These 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.
GWarning
If ice has formed on the road, tire traction will
be substantially reduced. Under such weather
conditions, drive, steer and brake with
extreme caution.
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
the freezing point.
Mercedes-Benz recommends a minimum tire
tread depth of 1/6 in (4 mm) for all four winter
tires ( Y page 482) to maintain normal driving
characteristics in winter. Winter tires can
reduce the braking distance on snow covered
surfaces in comparison to summer tires. The
braking distance is still much further than on
surfaces that are not icy or snowy. Take
appropriate care when driving.
! Avoid wheelspin. This can lead to damage
to the drive train.
Temperature
GWarning
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, representing the tire's resistance to
the build up 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. Furthermore, excessive temperature
can lead to sudden tire failure. 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
Tire labeling overview
The following markings are on the tire in
addition to the tire name (sales designation)
and the manufacturer's name:
Tire labeling495Tires and wheelsZ
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 which 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 494).
For further information on the load bearing
index, see load index ( Y page 498).
Speed index: speed index B specifies the
approved maximum speed of the tire.GWarning
Even when permitted by law, never operate a
vehicle at speeds greater than the maximum
speed rating of the tires.
Exceeding the maximum speed for which tires
are rated can lead to sudden tire failure,
causing loss of vehicle control and possibly
resulting in an accident and/or serious
personal injury and possible death, for you
and for others.
Regardless of the speed index always observe
the speed limits. Drive carefully and adapt
your driving style to the traffic conditions.
Summer tiresIndexSpeed ratingQup to 100 mph (160 km/h)Rup to 106 mph (170 km/h)Sup to 112 mph (180 km/h)Tup to 118 mph (190 km/h)Hup 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)
R 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).
Tire labeling497Tires and wheelsZ
Term definition for tires and loading
Tire ply composition and material
used
Describes the number of layers or the number
of rubber-coated belts in the tire tread and
the tire wall. These are made of steel, nylon,
polyester and other materials.
Bar
Metric unit for tire pressure. 14.5038 pounds
per square inch (psi) and 100 kilopascals
(kPa) are the equivalent of 1 bar.
DOT (Department of Transportation)
DOT marked tires fulfill the requirements of
the United States Department of
Transportation.
Average weight of the vehicle
occupants
The number of occupants for which the
vehicle is designed multiplied by 68 kilograms
(150 lb).
Uniform Tire Quality Grading
Standards
This is a uniform standard to grade the quality
of tires with regards to tread quality, tire
traction and temperature characteristics. The
quality grading assessment is made by the
manufacturer following specifications from
the U.S. government. The quality grade of a
tire is imprinted on the sidewall of the tire.
Recommended tire pressure
This is the recommended tire pressure for
your vehicle under normal driving conditions.
You will find the recommendation on the Tire
and Loading Information placard on the
B-pillar on the driver's side of your vehicle.
The recommended tire pressure provides the
best balance between handling
characteristics, ride comfort and wear.
Additional information on particular driving
conditions is located on the tire pressure
table on the inside of the fuel filler flap.
Increased vehicle weight due to
optional equipment
This is the combined weight of all standard
and optional equipment available for the
vehicle, regardless of whether it is actually
installed on the vehicle or not.
Wheel rim
This is 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. It specifies the speed range for
which the tire is approved. Specifies the
speed range for which the tire is approved.
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
500Term definition for tires and loadingTires and wheels
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 loaded vehicle weight
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.
Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the maximum axle load of one axle
by two.
PSI (pounds per square inch)
Standard unit of measurement for tire
pressure.
Aspect ratio
Relationship between tire height and tire
width in percent.
Tire pressure
Pressure inside the tire applying an outward
force to every square inch of the tire's
surface. The tire pressure is specified in
pounds per square inch (psi), in kilopascal
(kPa) or in bar. The tire pressure should only
be corrected when the tires are cold. For this,
the vehicle must have been stationary for at
least three hours or not have traveled more
than 1.6 km (1 mile) in this time.
Tire tread
The part of the tire that comes into contact
with the road.
Term definition for tires and loading501Tires and wheelsZ
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 interchanged. Check the tire pressures.
Information on changing a wheel and fitting
the spare wheel ( Y page 463).
! On vehicles installed with a tire pressure
monitor, electronic components are
located in the wheel.
Tire-mounting tools should not be applied
in the area of the valve, as this could
damage the electronic components.
Always have the tires changed at a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center.
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 install 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.
Storing wheels
Store wheels that are not being used in a cool,
dry and preferably dark place. Protect the
tires from contact with oil, grease and fuel.
Cleaning the wheels
GWarning
Do not use power washers with circular jet
nozzles (concentrated-power jets) to clean
your vehicle, especially for cleaning tires. You
could otherwise damage the tires and cause
an accident.
Wheel/tire combinations
Points to remember
GWarning
Observe the "Important safety notes"
( Y page 480).
! For safety reasons, Mercedes-Benz
recommends that you only use tires,
wheels and accessories which have been
approved by Mercedes-Benz specifically
for your vehicle.
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 with run-flat characteristics)
R MO1 = Mercedes-Benz Original (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
Wheel/tire combinations503Tires and wheelsZ