Page 337 of 364

If "P" precedes the size description: light
truck tires according to U.S. manufacturing
standards.
If
"T" precedes the size description: these are
compact emergency spare wheels at high tire
pressure, to be used only temporarily in an
emergency.
Tire width: tire width : shows the nominal
tire width in millimeters.
Height-width ratio: height-width ratio ; is
the ratio between tire height and tire width.
The aspect ratio is calculated by dividing the
tire width by the tire height. The resulting
quotient is given as a percentage.
Tire code: tire code = shows 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: B load bearing index
A (also load index) is a numerical code that
specifies the maximum load-bearing capacity
of a tire.
Do not overload the tires by exceeding the
specified load limit. The maximum
permissible load can be found on the
vehicle's Tire and Loading Information
placard on the B-pillar on the driver's side
(Y page 328).
Example:
Load-bearing index 91 indicates a maximum
load of 1356 lbs (615 kg) that the tires can
bear. For further information on the maximum
tire load in kilograms and pounds, see
(Y page 337).
For further information on the load bearing
index, see "Load index" ( Y page 336).Speed rating:
speed rating B specifies the
approved maximum speed of the tire.
i Tire data is vehicle-specific and may
deviate from the data in the example.
Regardless of the speed rating, always
observe the speed limits. Drive carefully and
adapt your driving style to the traffic
conditions.
i Since 2009, tires in Europe which
correspond to the noise limitations of
Directive ECE-R 117 show an >>S<<
(Sound) mark. This identification follows
the type approval number and has no
connection with the speed rating.
Summer tires Index Speed rating
Q up to 100 mph (160 km/h)
R up to 106 mph (170 km/h)
S up to 112 mph (180 km/h)
T up to 118 mph (190 km/h)
H up to 130 mph (210 km/h)
V up to 149 mph (240 km/h)
W up to 168 mph (270 km/h)
Y up to 186 mph (300 km/h)
ZR...Y up to 186 mph (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 "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 Tire labeling
335
Wheels and tires Z
Page 338 of 364

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(300 km/h).
R The size description for all tires with
maximum speeds of over 186 mph
(300 km/h) must include "ZR" 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 118 mph (190 km/h)
H M+S
4 up to 130 mph (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).
These tires have been developed
specifically for driving on snow.
When the electronic speed limiter is set, your
vehicle is prevented from exceeding 130 mph
(210 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 346).
Further information about reading tire data
can be obtained from any qualified specialist
workshop. Load index
In addition to the load bearing index, load
rating : may be imprinted after the letters
that identify speed rating B on the sidewall
of the tire (Y page 334).
R
If
no specification is given: no text (as in the
example above), represents a standard
load (SL) tire
R XL or Extra Load: represents a reinforced
tire
R Light Load: represents a light load tire
R C, D, E: represents a load range that
depends on the maximum load that the tire
can carry at a certain pressure
i Tire data is vehicle-specific and may
deviate from the data in the example.
4 Or M+S i for winter tires.336
Tire labeling
Wheels and tires
Page 339 of 364

Maximum load rating
Maximum tire load
: is the maximum
permissible weight for which the tire is
approved.
Do not overload the tires by exceeding the
specified load limit. The maximum
permissible load can be found on the
vehicle's Tire and Loading Information
placard on the B-pillar
on the driver's side
(Y page 328).
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration. DOT, Tire Identification Number (TIN)
U.S. tire regulations prescribe that every
manufacturer
of new tires or retreader has to
imprint a TIN in or on the sidewall of each tire
produced. The TIN is a unique identification number. The
TIN enables tire manufacturers to inform
purchasers of recalls and other safety- relevant matters. It makes it possible for the
purchaser
to easily identify the affected tires.
The TIN is made up of manufacturer
identification code ;, tire size =, tire type
code ? and manufacturing date A.
DOT (Department of Transportation): tire
symbol : indicates that the tire complies
with the requirements of the U.S. Department
of Transportation.
Manufacturer identification code:
manufacturer identification code ; provides
details on the tire manufacturer. New tires
have a code with two symbols. Retreaded
tires have a code with four symbols.
For further information about retreaded tires,
see ( Y page 318).
Tire size: identifier = describes the tire size.
Tire type code: tire type code ? can be
used by the manufacturer as a code to
describe specific characteristics of the tire.
Date of manufacture: date of manufacture
A provides information about the age of a
tire. The first and second positions represent
the week of manufacture, starting with "01"
for the first calendar week. Positions three
and four represent the year of manufacture.
For example, a tire that is marked with
"3208", was manufactured in week 32 in
2008.
i Tire data is vehicle-specific and may
deviate from the data in the example. Tire characteristics Tire labeling
337
Wheels and tires Z
Page 340 of 364

This information describes the type of tire
cord and the number of layers in
sidewall
: and under tire tread ;.
i Tire data is vehicle-specific and may
deviate from the data in the example. Definition of terms for tires and
loading
Tire ply composition and material used Describes the number of layers or the number
of rubber-coated belts in the tread and the
sidewall of the tire. 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.
Normal occupant weight
The number of occupants for which the
vehicle is designed multiplied by
68 kilograms (150 lbs).
Uniform
Tire Quality Grading StandardsA uniform standard to grade the quality of
tires
with regards to tread quality, tire traction
and temperature characteristics. Ratings are
determined by tire manufacturers using U.S.
government testing procedures. The ratings
are molded into the sidewall of the tire.
Recommended tire pressure The recommended tire pressure applies to
the tires mounted at the factory. The Tire and Loading Information placard
contains
the recommended tire pressures for
cold tires on a fully loaded vehicle and for the
maximum permissible vehicle speed.
The tire pressure table contains the
recommended pressures for cold tires for
various operating conditions, i.e. differing
load and speed conditions.
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.
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 rating The speed rating is part of the tire
identification.
It 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 not338
Tire labeling
Wheels and tires
Page 341 of 364

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 loaded vehicle weight The maximum weight is the sum of:
R
the curb weight of the vehicle
R the weight of the accessories
R the load limit
R the weight of the factory installed optional
equipment
Kilopascal (kPa) Metric unit for tire pressure. 6.9 kPa
corresponds to 1 psi. Another unit for tire
pressure
is bar. 100 kilopascals (kPa) are 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.
Curb 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 in the vehicle, but does
not include passengers or luggage. Maximum load rating The maximum tire load is the maximum
permissible weight in kilograms or lbs 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) A standard unit of measure for tire pressure.
Aspect ratio
Relationship between tire height and tire
width in percent.
Tire pressure
This is pressure inside the tire applying an
outward
force to each 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.
Cold tire pressure The tires are cold:
R
if the vehicle has been parked without
direct
sunlight on the tires for at least three
hours and
R if the vehicle has not been driven further
than 1 mile (1.6 km)
Tread The part of the tire that comes into contact
with the road. Tire labeling
339
Wheels and tires Z
Page 342 of 364

Bead
The tire bead ensures that the tire sits
securely
on the wheel. There are several steel
wires in the bead to prevent the tire from
coming loose from the wheel rim.
Sidewall The part of the tire between the tread and the
bead.
Weight of optional extras
The combined weight of those optional extras
that weigh more than the replaced standard
parts and more than 2.3 kg
(5 lbs). These
optional extras, such as high-performance
brakes, level control, a roof rack or a high-
performance battery, are not included in the
curb weight and the weight of the
accessories.
TIN (Tire Identification Number) This is a unique identifier which can be used
by a tire manufacturer to identify tires, for
example
for a product recall, and thus identify
the purchasers. The TIN is made up of the
manufacturer's identity code, tire size, tire
type code and the manufacturing date.
Load bearing index The load bearing index (also load index) is a
code
that contains the maximum load bearing
capacity of a tire.
Traction Traction is the result of friction between the
tires and the road surface.
TWR (Tongue Weight Rating)
The TWR specifies the maximum permissible
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 á in
(1.6 mm) has been reached.
Occupant distribution The distribution of occupants in a vehicle at
their designated seating positions.
Total load limit
Nominal load and luggage load plus 150 lbs
(68 kg) multiplied by the number of seats in
the vehicle.
Changing a wheel
Flat tire
The "Breakdown assistance" section
(Y
page 304) contains information and notes
on how to deal with a flat tire. Interchanging the wheels
G
WARNING
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. G
WARNING
Have the tightening torque checked after
changing a wheel. The wheels could come
loose if they are not tightened to a torque of
96 lb-ft (130 Nm
).
Only use genuine Mercedes-Benz wheel bolts
specified for your vehicle's rims.
! On vehicles equipped with a tire pressure
monitor, electronic components are
located in the wheel. 340
Changing a wheel
Wheels and tires
Page 343 of 364

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.
Interchanging the front and rear wheels of
differing dimensions can render the general
operating permit invalid.
Always pay attention to the instructions and
safety notices in the section on "Changing a
wheel and mounting a spare wheel"
(Y page 341).
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
replaced every 3000 to
6000 miles(5000 to 10,000 km), or earlier if
tire wear necessitates it. 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 pressure and
reactivate the tire pressure monitor
(Y page 325) if necessary. 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 the spare wheel against the
direction of rotation. Adhere to the time
restriction on use as well as the speed
limitation specified on the spare wheel. Storing wheels
Store tires that are not being used in a cool,
dry and preferably dark place. Protect the
tires from oil, grease, gasoline and diesel. Cleaning the wheels
G
WARNING
Do not use power washers with circular-jet
nozzles
(dirt grinders) to clean your vehicle, in
particular the tires. You could otherwise
damage the tires and cause an accident. Mounting a wheel
Preparing the vehicle G
WARNING
You must remove the spare wheel from the
spare wheel carrier before lifting the vehicle.
Otherwise the vehicle could fall off the jack
and injure you or others.
X Prepare the vehicle as described
(Y page 304).
X Remove the vehicle tool kit and the jack
(Y page 302).
X Secure the vehicle to prevent it from rolling
away.
X Remove the spare wheel from the spare
wheel bracket ( Y page 303).
i Vehicles without a spare wheel or
emergency spare wheel are not equipped
with
a tire-change tool kit at the factory. For
more information on which tools are
required to perform a wheel change on your
vehicle e.g. lug wrench or jack, consult an
authorized Mercedes-Benz Center.
Securing the vehicle to prevent it from
rolling away X
On level ground: place chocks or other
suitable items under the front and rear of Changing a wheel
341
Wheels and tires Z
Page 344 of 364

the wheel that is diagonally opposite the
wheel you wish to change.
X On downhill gradients: place chocks or
other suitable items in front of the wheels
of the front and rear axle.
Raising the vehicle G
WARNING
If you do not position the jack correctly at the
appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate
jacking point of the vehicle. The base of the
jack must be positioned vertically, directly
under the jacking point of the vehicle.
! The jack is designed exclusively for
jacking
up the vehicle at the jacking points.
Otherwise, your vehicle could be damaged.
The following must be observed when raising
the vehicle:
R to raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If used
incorrectly, the jack could tip over with the
vehicle raised.
R the jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It is not suited for
performing maintenance work under the
vehicle.
R avoid changing the wheel on uphill and
downhill slopes.
R before raising the vehicle, secure it from
rolling away by applying the parking brake
and inserting wheel chocks. Never
disengage the parking brake while the
vehicle is raised.
R the jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a
large, load-bearing underlay must be used.
On a slippery surface, a non-slip underlay
must be used, e.g. rubber mats. R
do not use wooden blocks or similar
objects as a jack underlay. Otherwise, the
jack will not be able to achieve its load-
bearing capacity due to the restricted
height.
R make sure that the distance between the
underside
of the tires and the ground does
not exceed 1.2 inches (3 cm).
R never place your hands and feet under the
raised vehicle.
R never lie under the raised vehicle.
R never start the engine when the vehicle is
raised.
R never open or close a door or the tailgate
when the vehicle is raised.
R make sure that no persons are present in
the vehicle when the vehicle is raised. X
Using lug wrench :, loosen the bolts on
the
wheel you wish to change by about one
full turn. Do not unscrew the wheel bolts
completely. Pump lever
;
Notch on pump lever342
Changing a wheel
Wheels and tires