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Tire labeling
Overview
:Uniform Tire Quality Grading Standards
(
Ypage 307)
;Department of Transportation, Tire Iden-
tification Number (
Ypage 306)
=Maximum load rating (Ypage 305)
?Maximum tire pressures (Ypage 294)
AManufacturer
BTire material (Ypage 306)
CTire size designation, load-bearing capa-
city and speed rating (
Ypage 303)
DLoad index (Ypage 305)
ETire name
The markings described above are on the tire
in addition to the tire name (sales designa-
tion) and the manufacturer's name.
iTire data is vehicle-specific and may devi-
ate from the data in the example.
Tire size designation, load-bearing
capacity and speed rating
GWARNING
Exceeding the stated tire load-bearing capa-
city and the approved maximum speed could
lead to tire damage or the tire bursting. There is a risk of accident.
Therefore, only use tire types and sizes
approved for your vehicle model. Observe the
tire load rating and speed rating required for
your vehicle.
:Tire width
;Nominal aspect ratio in %
=Tire code
?Rim diameter
ALoad bearing index
BSpeed rating
General: depending on the manufacturer's
standards, the size imprinted in the tire wall
may not contain any letters or may contain
one letter that precedes the size description.
If there is no letter preceding the size descrip-
tion (as shown above): these are passenger
vehicle tires according to European manufac-
turing standards.
If "P" precedes the size description: these are
passenger vehicle tires according to U.S.
manufacturing standards.
If "LT" precedes the size description: these
are light truck tires according to U.S. manu-
facturing standards.
If "T" precedes the size description: compactemergency wheels with high tire pressure
that are only designed for temporary use in an
emergency.
Tire width: tire width:shows the nominal
tire width in millimeters.
Aspect ratio: aspect ratio;is the size ratio
between the tire height and tire width and is
shown in percent. The aspect ratio is calcu-
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lated 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.
Rim diameter: rim diameter?is the diam-
eter of the bead seat, not the diameter of the
rim flange. The rim diameter is specified in
inches (in).
Load-bearing index: load-bearing indexA
is a numerical code that specifies the maxi-
mum load-bearing capacity of a tire.
Do not overload the tires by exceeding the
specified load limit. The maximum permissi-
ble load can be found on the vehicle's Tire and
Loading Information placard on the B-pillar on
the driver's side (
Ypage 298).
Example:
Load-bearing index 91 indicates a maximum
load of 1,356 lb (615 kg) that the tires can
bear. For further information on the maximum
tire load in kilograms and lbs, see
(
Ypage 305).
For further information on the load bearing
index, see "Load index" (
Ypage 305).
Speed rating: speed ratingBspecifies the
approved maximum speed of the tire.
iTire data is vehicle-specific and may devi-
ate 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 condi-
tions.
Summer tires
IndexSpeed rating
Qup 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)
IndexSpeed rating
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)over 186 mph (300km/ h)
ZRover 149 mph (240km/ h)
ROptionally, 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).
RIf a service specification is available, the
maximum speed is limited according to the
speed rating in the service specification.
Example: 245/40 ZR18 97 Y.In this exam-
ple, "97 Y" is the service specification. The
letter "Y" represents the speed rating. The
maximum speed of the tire is limited to
186 mph (300 km/h).
If the size description of your tire includes
"ZR" and there are no service specifica-
tions, ask the tire manufacturer in order to
find out the maximum speed.
RThe size description for all tires with maxi-
mum speeds of over 186 mph (300 km/h)
must include "ZR", andthe service specifi-
cation must be given in parentheses. Exam-
ple: 275/40 ZR 18 (99 Y). 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
IndexSpeed rating
Q M+S1up to 100 mph (160 km/h)
T M+S1up to 118 mph (190 km/h)
1Or M+S ifor winter tires.
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IndexSpeed rating
H M+S1up to 130 mph (210 km/h)
V M+S1up to 149 mph (240 km/h)
iNot 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 isnowflake symbol on
the tire wall. Tires with this marking fulfill
the requirements of the Rubber Manufac-
turers Association (RMA) and the Rubber
Association of Canada (RAC) regarding the
tire traction on snow. They have been espe-
cially developed for driving on snow.
An electronic speed limiter prevents your
vehicle from exceeding the following speeds:
Rall vehicles (except AMG vehicles):
130 mph (210 km/h)
RAMG vehicles: 155 mph (250 km/h)
RAMG vehicles with Performance Package
(Wagon): 174 mph (280km/ h)
RAMG vehicles with Performance Package
(Sedan): 186 mph (300 km/h)
The speed rating of tires mounted at the fac- tory 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 (
Ypage 314).
Further information about reading tire data
can be obtained from any qualified specialist
workshop.
Load index
In addition to the load bearing index, load
index :may be imprinted after the letters
that identify speed index Bon the sidewall of
the tire (
Ypage 303).
RIf no specification is given: no text (as in the
example above), represents a standard
load (SL) tire
RXL or Extra Load: represents a reinforced
tire
RLight Load: represents a light load tire
RC, D, E: represents a load range that
depends on the maximum load that the tire
can carry at a certain pressure
iTire data is vehicle-specific and may devi-
ate from the data in the example.
Maximum load rating
Maximum tire load :is the maximum per-
missible weight for which the tire is approved.
Do not overload the tires by exceeding the
specified load limit. The maximum permissi-
1Or M+S ifor winter tires.
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ble load can be found on the vehicle's Tire and
Loading Information placard on the B-pillar on
the driver's side (
Ypage 298).
iThe actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
DOT, Tire Identification Number (TIN)
US tire regulations stipulate that every tire
manufacturer or retreader must imprint a TIN
in or on the sidewall of each tire produced.
The TIN is a unique identification number. The
TIN enables the tire manufacturers or retread-
ers to inform purchasers of recalls and other
safety-relevant matters. It makes it possible
for the purchaser to easily identify the affec-
ted tires.
The TIN is made up of manufacturer identifi-
cation code ;, tire size=, tire type code ?
and manufacturing date A.
DOT (Department of Transportation): tire
symbol :marks that the tire complies with
the requirements of the U.S. Department of
Transportation.
Manufacturer identification code: manu-
facturer 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 (
Ypage 288).
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 "2614" was
manufactured in week 26 in 2014.
iTire data is vehicle-specific and may devi-
ate from the data in the example.
Tire characteristics
This information describes the type of tire
cord and the number of layers in sidewall :
and under tire tread ;.
iTire data is vehicle-specific and may devi-
ate from the data in the example.
Definition of terms for tires and loading
Tire ply composition and material used
Describes the number of plies or the number
of layers of rubber-coated fabric in the tire
tread and sidewall. 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.
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DOT (Department of Transportation)
DOT-markedtires fulfill th erequirements of
th e U S Departmen tof Transportation .
Normal occupant weigh t
The number of occupant sfo rwhic hth evehi-
cle is designed multiplie dby 68 kilograms
(15 0lbs) .
Unifor mTire Qualit yGrading Standards
A uniform standard to grade th equalit yof
tires wit hregards to tread quality, tire traction
and temperature characteristics .The qualit y
gradin gassessmen tis made by th emanufac -
turer following specification sfrom th eU.S.
government. The ratings are molded into th e
sidewall of th etire.
Recommended tire pressure s
The recommended tire pressur eapplies to
th etires mounted at th efactory.
The Tir eand Loadin gInformation placard con-
tains th erecommended tire pressures fo r
cold tires on afull yloade dvehicl eand fo rth e
maximum permissibl evehicl espeed.
The tire pressur etable contain sth erecom-
mended pressures fo rcold tires fo rvarious
operating conditions, i.e. differin gload and
speed conditions.
Increased vehicle weigh tdu eto optiona l
equipment
The combine dweight of all standard and
optional equipmen tavailable fo rth evehicle,
regardless of whether it is a
ctually installed
on th evehicl eor not.
Ri m
This is th epart of th ewhee lon whic hth etire
is mounted.
GAW R(Gross Axle Weight Rating)
The GAW Ris th emaximum gross axl eweight
rating. The actual load on an axl emus tnever
exceed th egross axl eweight rating. The
gross axl eweight ratin gcan be found on th e
vehicl eidentification plat eon th eB-pillar on
th edriver's side . Speed rating
The speed ratin
gis part of th etire identifica-
tion .It specifies th espeed range fo rwhic hth e
tire is approved.
GV W(Gross Vehicle Weight )
The gross vehicl eweight includes th eweight
of th evehicl eincludin gfuel ,tools ,th espar e
wheel, accessories installed ,occupants, lug-
gage and th edrawbar noseweight ,if applica-
ble. The gross vehicl eweight mus tno texceed
th egross vehicl eweight ratin gGVWR as
specified on th evehicl eidentification plat eon
th eB-pillar on th edriver's side .
GVWR (Gross Vehicle Weight Rating)
The GVWR is th emaximum permissibl egross
weight of afull yloade dvehicl e(the weight of
th evehicl eincludin gall accessories, occu-
pants ,fuel, luggage and th edrawbar nose-
weight ,if applicable). The gross vehicl e
weight ratin gis specified on th
eve
hicl eiden -
tification plat eon th eB-pillar on th edriver's
side .
Maximum loaded vehicle weigh t
The maximum weight is th esum of :
Rthecur bweight of th evehicl e
Rtheweight of th eaccessories
Rth eload limi t
Rtheweight of th efactory installed optional
equipmen t
Kilopascal (kPa)
Metric uni tfo rtire pressure. 6. 9kP acorre-
spond sto 1psi .Another uni tfo rtire pressur e
is bar. 10 0kilopascal s(kPa) are th eequiva-
len tof 1bar.
Load index
In addition to th eload-bearin gindex ,th eload
index may also be imprinte don th esidewall of
th etire. This specifies th eload-bearin gcapa-
cit ymor eprecisely.
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Curb weight
The weight of a vehicle with standard equip-
ment including the maximum capacity of fuel,
oil and coolant. It also includes the air-condi-
tioning system and optional equipment if
these are installed in the vehicle, but does not
include passengers or luggage.
Maximum load rating
The maximum load rating 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
Pressure inside the tire applying an outward
force to every square inch of the tire's sur-
face. The tire pressure is specified in pounds
per square inch (psi), in kilopascal (kPa) or in
bar. The tire pressure should only be correc-
ted when the tires are cold.
Cold tire pressure
The tires are cold:
Rif the vehicle has been parked without
direct sunlight on the tires for at least three
hours and
Rif 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.
Bead
The tire bead ensures that the tire
sits
securely on t
he 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 accesso-
ries.
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.
Tread wear indicators
Narrow bars (tread wear bars) that are dis-
tributed over the tire tread. If the tire tread is
level with the bars, the wear limit of áin
(1.6 mm) has been reached.
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Occupant distribution
The distribution of occupants in a vehicle at
their designated seating positions.
Total load limit
Nominal load and luggage load plus 68 kg
(150 lbs) multiplied by the number of seats in
the vehicle.
Changing a wheel
Flat tire
The "Breakdown assistance" section
(
Ypage 271) 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"
(
Ypage 272).
Vehicle with emergency spare wheel: in
the event of a flat tire, the emergency spare
wheel is mounted as described under "Mount-
ing a wheel" (
Ypage 309).
Rotating the wheels
GWARNING
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 acci-
dent.
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 loca-
ted in the wheel.
Tire-mounting tools should not be used
near the valve. This could damage the elec- tronic components.
Only have tires changed at a qualified spe-
cialist workshop. Always observe the instructions and safety
notes in the "Mounting a wheel" section
(
Ypage 309).
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 inter-
vals in the tire manufacturer's warranty book
in your vehicle documents. If no warranty
book is available, the tires should be rotated
every 3,000 to 6,000 miles (5,000 to
10,000 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 rotated. Check the tire pressure and reac-
tivate the tire pressure monitor if necessary
(
Ypage 297).
Direction of rotation
Tires with a specified direction of rotation
have additional benefits, e.g. if there is a risk of hydroplaning. These advantages can only
be gained if the tires are installed correspond-
ing to the direction of rotation.
An arrow on the sidewall of the tire indicates its correct direction of rotation.
Storing wheels
Store wheels that are not being used in a cool,
dry and preferably dark place. Protect the
tires from oil, grease, gasoline and diesel.
Mounting a wheel
Preparing the vehicle
XStop the vehicle on solid, non-slippery and
level ground.
XApply the parking brake.
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XBring the front wheels into the straight-
ahead position.
XShift the transmission to positionP.
XVehicles with AIRMATIC: make sure that
"normal" level is selected (
Ypage 166).
XSwitch off the engine.
XRemove the SmartKey from the ignition
lock.
or, on vehicles with KEYLESS ‑GO:
XOpen the driver's door.
The on-board electronics now have status
0. This is the same as the SmartKey having
been removed.
XRemove the Start/Stop button from the
ignition lock (
Ypage 138).
XIf included in the vehicle equipment,
remove the tire-change tool kit from the
vehicle (
Ypage 270).
XSafeguard the vehicle against rolling away.
Securing the vehicle to prevent it from
rolling away
If your vehicle is equipped with a wheel chock,
it can be found in the tire-change tool kit
(
Ypage 270).
The folding wheel chock is an additional
safety measure to prevent the vehicle from
rolling away, for example when changing a
wheel.
XFold both plates upwards :.
XFold out lower plate;.
XGuide the lugs on the lower plate fully into
the openings in base plate =.
Securing the vehicle on level ground (example:
Sedan)
XOn level ground:place chocks or other
suitable items under the front and rear of
the wheel that is diagonally opposite the
wheel you wish to change.
Securing the vehicle on slight downhill gradients
(example: Sedan)
XOn light downhill gradients: place
chocks or other suitable items in front of
the wheels of the front and rear axle.
Raising the vehicle
GWARNING
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 jack-
ing point of the vehicle. The base of the jack
must be positioned vertically, directly under
the jacking point of the vehicle.
310Changing a wheel
Wheels and tires