Page 321 of 350

Step 3
Example 1 Example 2 Example 3
Permissible load
(maximum gross
vehicle weight rat-
ing from the Tire
and Loading Infor-
mation placard
minus the gross
weight of all occu-
pants)
1500 lbs (680 kg)
Ò
750 lbs (340 kg) =
750 lbs (340 kg) 1500 lbs (680 kg)
Ò
540 lbs (245 kg)
=960 lbs (435 kg) 1500 lbs (680 kg)
Ò
150 lbs (68 kg) =
1350 lbs (612 kg) Vehicle identification plate
Even if you have calculated the total load
carefully, you should still make sure that the
gross vehicle weight rating and the gross axle weight rating are not exceeded. Details can
be found on the vehicle identification plate on the B-pillar on the driver's side of the vehicle
(Y page 316).
Gross vehicle weight rating: the gross
weight of the vehicle, all passengers, load and
trailer load/noseweight (if applicable) must
not exceed the gross vehicle weight rating.
Gross Axle Weight Rating (GAWR): the
maximum permissible weight that can be car- ried by one axle (front or rear axle).
To ensure that your vehicle does not exceed
the maximum permissible values (gross vehi-
cle weight and maximum gross axle weight
rating), have your loaded vehicle (including
driver, occupants, load and full trailer load if
applicable) weighed on a suitable vehicle
weighbridge. Trailer load/noseweight
The trailer load/noseweight affects the gross
weight of the vehicle. If a trailer is attached,
the trailer load/noseweight is included in the
load along with occupants and luggage. The
trailer load/noseweight is usually approx-
imately 10 % of the gross weight of the trailer and its load. Only use a trailer tow hitch that has been
approved for your vehicle by Mercedes-Benz.
Comply with the manufacturer's operating
instructions for operation, care and mainte-
nance. Uniform Tire Quality Grading Stand-
ards Overview of Tire Quality Grading
Standards Uniform Tire Quality Grading Standards are
U.S. government specifications. Their pur-
pose is to provide drivers with uniform relia-
ble 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 Uniform Tire Quality Grading Standards
319Wheels and tires Z
Page 322 of 350

are provided with the corresponding quality
grading markings on the sidewall of the tire.
Where applicable, the tire grading informa-
tion 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 test track as a tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use, how-
ever, and may depart significantly from the
norm, due to variations in driving habits, ser-
vice practices and differences in road char-
acteristics 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, cor- nering, hydroplaning, or peak traction char-
acteristics.
! 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 surfa-
ces.
You should pay special attention to road con-
ditions when temperatures are around freez-
ing point.
Mercedes-Benz recommends a minimum
tread depth of ãin (4 mm) on all four winter
tires. Observe the legally required minimum
tire tread depth (Y page 307). 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 308). Temperature
G
WARNING
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underinfla-
tion, 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 dis- sipate 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 tempera-
ture can lead to sudden tire failure. The grade
C corresponds to a level of performance
which all passenger car tires must meet under 320
Uniform Tire Quality Grading StandardsWheels and tires
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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 of tire labeling
:
Uniform tire Quality Grading Standard
(Y page 325)
; DOT tire Identification Number
(Ypage 324)
= Maximum tire load (Y page 323)
? Maximum tire pressures (Y page 312)
A Manufacturer
B Tire material (Y page 324)
C Tire size designation, load-bearing capa-
city and speed rating (Y page 321)
D Load identification (Y page 323)
E Tire name
The markings described above are on the tire in addition to the tire name (sales designa-
tion) and the manufacturer's name.
i Tire data is vehicle-specific and may devi-
ate from the data in the example. Tire size designation, load-bearing
capacity and speed rating
G
WARNING
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
; Height-width ratio in percentage
= Tire code
? Rim diameter
A Load bearing index
B Speed rating
General: depending on the manufacturer's
standards, a letter is imprinted into the tire
wall before 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:
passenger vehicle tires according to U.S.
manufacturing standards.
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 Tire labeling
321Wheels and tires Z
Page 324 of 350

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 man-
ufacturer (e.g. 245/40 ZR 18).
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).
The load-bearing index: load-bearing index
A (also load index), is a code that contains
the maximum 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 (Y page 316).
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 pounds, see
(Y page 323).
For further information on the load bearing
index, see "Load index" (Y page 323).
Speed rating: speed ratingBspecifies the
approved maximum speed of the tire.
i Tire 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. i
Since 2009, tires in Europe which corre-
spond 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 Aand speed rating B.
R 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.
If 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 and 322
Tire labelingWheels and tires
Page 325 of 350

the maximum speed of the tire is limited to
186 mph (300 km/h ).
R The 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 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 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). These tires
have been developed specifically for driv-
ing 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 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 (Y page 333).
Further information about reading tire data
can be obtained from any qualified specialist workshop. Load index
In addition to the load bearing index, load rat-
ing :may be imprinted after the letters that
identify speed rating Bon the sidewall of the
tire (Y page 321).
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 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.
4 Or M+S ifor winter tires. Tire labeling
323Wheels and tires Z
Page 326 of 350

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 (Y page 316).
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 pur-
chasers of recalls and other safety-relevant
matters. It makes it possible for the pur-
chaser to easily identify the affected 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 :indicates 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 (Y page 306). 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 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 ;.
i Tire data is vehicle-specific and may devi-
ate from the data in the example. Definition of terms for tires and load-
ing
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. 324
Tire labelingWheels and tires
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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 U S Department of Transportation.
Normal occupant weight The number of occupants for which the vehi-
cle is designed multiplied by 68 kilograms
(150 lbs).
Uniform Tire Quality Grading Standards 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 manufac- turer following specifications from the U.S.
government. The ratings are molded into the
sidewall of the tire.
Recommended tire pressures The recommended tire pressure applies to
the tires mounted at the factory.
The Tire and Loading Information placard con- tains the recommended tire pressures for
cold tires on a fully loaded vehicle and for themaximum permissible vehicle speed.
The tire pressure table contains the recom-
mended pressures for cold tires for various
operating conditions, i.e. differing load and
speed conditions.
Increased vehicle weight due to
optional equipment 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 identifica-
tion. 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, lug-
gage and the drawbar noseweight, if applica-
ble. The gross vehicle weight must not 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, occu-
pants, fuel, luggage and the drawbar nose-
weight, if applicable). The gross vehicle
weight rating is specified on the vehicle iden-
tification plate on the B-pillar on the driver's
side. Tire labeling
325Wheels and tires Z
Page 328 of 350

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 corre-
sponds to 1 psi. Another unit for tire pressure
is bar. 100 kilopascals (kPa) are the equiva-
lent 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 capa- city more precisely.
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 notinclude 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 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 kilopascals
(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.
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 326
Tire labelingWheels and tires