set, these incorrect values will be moni-
tored.
X Also observe the notes in the section on tire
pressures (Y page 445).
X Make sure that the SmartKey is in position
2 in the ignition lock (Y page 189).
X Use ò on the steering wheel to call up
the list of menus.
X Press the 9or: button on the steer-
ing wheel to select the Service
Service menu.
X Press the abutton.
X Press the 9or: button to select
Tire Pressure Tire Pressure.
X Press the abutton.
The Run Flat Indicator Active
Run Flat Indicator Active
Press 'OK' to Restart
Press 'OK' to Restart message
appears in the multifunction display.
If you wish to confirm the restart: X Press the abutton.
The Tire Pressure Now OK?
Tire Pressure Now OK? message
appears in the multifunction display.
X Press the 9or: button to select
Yes
Yes.
X Press the abutton.
The Run Flat Indicator Restarted
Run Flat Indicator Restarted
message appears in the multifunction dis-
play.
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 If the Tire Pressure Now OK? Tire Pressure Now OK? message
appears, use the 9or: button to
select Cancel
Cancel.
X Press the abutton.
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 permis-
sible vehicle load. It also contains details
of the tire sizes and corresponding pres-
sures for tires mounted 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 occu-
pants, the fuel and the cargo. You can
also find information about the maximum gross axle weight rating on the front and
rear axle.
The maximum gross axle weight rating is the maximum weight that can be carried
by one axle (front or rear axle). Never
exceed the maximum load or the maxi-
mum gross axle weight rating for the
front or rear axle. Loading the vehicle
453Wheels and tires Z
Example: steps 1 to 3
The following table shows examples on how to calculate total and cargo load capacities with varying seating configurations and number and size of occupants. The following examples usea load limit of 1500 lbs (680 kg). This is for illustration purposes only. Make sure you are
using the actual load limit for your vehicle stated on your vehicle's Tire and Loading Information
placard (Y page 453).
The greater the combined weight of the occupants, the lower the maximum luggage load.
Example 1
Step 1
R Combined maximum weight of occupants and load (data from the Tire and Loading Infor-
mation placard): 1500 lbs (680 kg)
Step 2
R Number of people in the vehicle (driver and occupants): 5
R Distribution of the occupants
- Front: 2
- Rear: 3
R Weight of the occupants
- Occupant 1: 150 lbs (68 kg)
- Occupant 2: 180 lbs (82 kg)
- Occupant 3: 160 lbs (73 kg)
- Occupant 4: 140 lbs (63 kg)
- Occupant 5: 120 lbs (54 kg)
R Tota l weight of all occupants: 750 lbs (340 kg)
Step 3
R Perm issible load (maximum gross vehicle weight rating from the Tire and Loading Informa-
tion placard minus the gross weight of all occupants):
1500 lbs (680 kg) Ò750 lbs (340 kg) = 750 lbs (340 kg)
Example 2
Step 1
R Combined maximum weight of occupants and load (data from the Tire and Loading Infor-
mation placard): 1500 lbs (680 kg)
Step 2
R Number of peop le in the vehicle (driver and occupants): 3
R Distribution of the occupants
- Front: 1
- Rear: 2 456
Loading the vehicleWheels and tires
R
Weight of the occupants
- Occupant 1: 200 lbs (91 kg)
- Occupant 2: 190 lbs (86 kg)
- Occupant 3: 150 lbs (68 kg)
R Total weight of all occupants: 540 lbs (245 kg)
Step 3
R Permissible load (maximum gross vehicle weight rating from the Tire and Loading Informa-
tion placard minus the gross weight of all occupants):
1500 lbs (680 kg) Ò540 lbs (245 kg) =960 lbs (435 kg)
Example 3
Step 1
R Combined maximum weight of occupants and load (data from the Tire and Loading Infor-
mation placard): 1500 lbs (680 kg)
Step 2
R Number of people in the vehicle (driver and occupants): 2
R Distribution of the occupants:
- Front: 1
R Weight of the occupants
- Occupant 1: 150 lbs (68 kg)
R Total weight of all occupants: 150 lbs (68 kg)
Step 3
R Permissible load (maximum gross vehicle weight rating from the Tire and Loading Informa-
tion placard minus the gross weight of all occupants):
1500 lbs (680 kg) Ò150 lbs (68 kg) = 1350 lbs (612 kg) Vehicle identification plate
Even if you have calculated the total cargo
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 453).
Permissible Gross Vehicle Weight Rating
(GVWR): the gross weight of the vehicle, all
passengers, load and trailer load/noseweight (if applicable) must not exceed the permissi-
ble gross vehicle weight.
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, cargo, and full trailer load if applicable) weighed on a suitable vehicle
weighbridge. Loading the vehicle
457Wheels and tires Z
All about wheels and tires
Uniform Tire Quality Grading Stand-
ards
Overview of Tire Quality Grading Stand- ards 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
are provided with the corresponding quality
grading markings on the sidewall of the tire.
Quality grades can be found, where applica-
ble, 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, 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 wet pavement 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 443). Winter tires can
reduce the braking distance on snow-covered surfaces in comparison with summer tires.
The braking distance is still much further than 458
All about wheels and tiresWheels and ti
res
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 444).
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. They represent the tire's resistance to the generation of heat and its ability to dissi-pate heat when tested under controlled con-
ditions 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
(Ypage 463)
; DOT, Tire Identification Number
(Ypage 462)
= Maximum tire load (Y page 462)
? Maximum tire pressure (Y page 448)
A Manufacturer
B Tire material (Y page 463)
C Tire size designation, load-bearing capa-
city and speed rating (Y page 459)
D Load index (Y page 462)
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. All about wheels and tires
459Wheels and tires
Z
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
A Load bearing index
B Speed 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: 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.
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- 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.
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).
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 onthe driver's side (Y page 453).
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
(Y page 462).
For further information on the load bearing
index, see "Load index" (Y page 462).
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.
Summer tires Index Speed rating
Q up to 100 mph (160 km/h)
R up to 106 mph (170 km/h)460
All about wheels and tiresWheels and tires
Index Speed rating
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. 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
1 up to 100 mph (160 km/h)
T M+S
1 up to 118 mph (190 km/h)
H M+S
1 up to 130 mph (210 km/h)
V M+S
1 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) 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 a speed of 130mph
(210km/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 471).
Further information about reading tire data
can be obtained from any qualified specialist workshop.
1 Or M+S ifor winter tires. All about wheels and tires
461Wheels and tires Z
Load index
In addition to the load-bearing index, load
index
:may also be imprinted on the side-
wall of the tire. You will find this after the let-
ter that identifies the speed rating
(Y page 459).
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.
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 onthe driver's side (Y page 453).
i The 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.
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. 462
All about wheels and tiresWheels and tires