Page 321 of 358

have changed the tire pressure. However, you
can also define reference values manually as
described here. The tire pressure monitor
then monitors the new tire pressure values.
XSet the tire pressure to the value recom-
mended for the corresponding driving sit-
uation on the Tire and Loading Information
placard on the driver's side
B-pillar (
Ypage 311).
Additional tire pressure values for different
loads can also be found on the tire pressure
table on the inside of the fuel filler flap
(
Ypage 311).
XMake sure that the tire pressure is correct
on all four wheels.
XMake sure that the SmartKey is in position 2 in the ignition lock.
XPress the =or; button on the steer-
ing wheel to select the Serv.
menu.
XPress the9or: button to select
Tire Pressure
.
XPress the abutton.
The multifunction display shows the cur-
rent tire pressure for the individual tires or
the Tire
pressurewillbedisplayed
after driving a few minutesmes-
sage.
XPress the :button.
The Use Current Pressures as New
Reference Valuesmessage appears in
the multifunction display.
If you wish to confirm the restart:
XPress the abutton.
The Tire Press. Monitor Restarted
message appears in the multifunction dis-
play.
After driving for a few minutes, the system
checks whether the current tire pressures
are within the specified range. The new tire
pressures are then accepted as reference
values and monitored. If you wish to cancel the restart:
XPress the
%button.
The tire pressure values stored at the last
restart will continue to be monitored.
Radio type approval for the tire pres-
sure monitor
CountryRadio type approval number
USAFCC ID: MRXMW2433A
FCC ID: MRXGG4
FCC ID: MRXMC34MA4
CanadaIC: 2546A-MW2433A
IC: 2546A-GG4
IC: 2546A-MC34MA4
Loading the vehicle
Instruction labels for tires and loads
GWARNING
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
Loading the vehicle319
Wheels and tires
Z
Page 322 of 358

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.
:B-pillar, driver's side
Maximum permissible gross vehicle
weight rating
XSpecification for maximum gross vehicle
weight:is listed in the Tire and Loading
Information placard: "The combined weight of occupants and cargo should never
exceed XXX kilograms or XXX lbs."
The gross weight of all vehicle occupants,
load and luggage must not exceed the speci-
fied value.
iThe specifications shown on the Tire and
Loading Information placard in the illustra-
tion are examples. The maximum permis-
sible gross vehicle weight rating is vehicle-
specific and may differ from that in the
illustration. You can find the valid maximum permissible gross vehicle weight rating for
your vehicle on the Tire and Loading Infor-
mation placard.
Number of seats
Maximum number of seats :indicates the
maximum number of occupants allowed to
travel in the vehicle. This information can be
found on the Tire and Loading Information
placard.
iThe specifications shown on the Tire and
Loading Information placard in the illustra-
tion are examples. The number of seats is
vehicle-specific and can differ from the
details shown. The number of seats in your vehicle can be found on the Tire and Load-
ing Information placard.
Determining the correct load limit
Step-by-step instructions
The following steps have been developed as
required of all manufacturers under Title 49,
Code of U.S. Federal Regulations, Part 575
pursuant to the "National Traffic and Motor
Vehicle Safety Act of 1966".
320Loading the vehicle
Wheels and tires
Page 323 of 358

XStep 1:Locate the statement "The com-
bined weight of occupants and cargo
should never exceed XXX kg or XXX lbs." on
your vehicle’s Tire and Loading Information
placard.
XStep 2: Determine the combined weight of
the driver and passengers that will be riding
in your vehicle.
XStep 3: Subtract the combined weight of
the driver and passengers from XXX kilo-
grams or XXX lbs.
XStep 4: The resulting figure equals the
available amount of cargo and luggage load
capacity. For example, if the "XXX" amount
equals 1400 lbs and there will be five
150-lb passengers in your vehicle, the
amount of available cargo and luggage load
capacity is 650 lbs (1400 - 750 (5 x 150) =
650 lbs).
XStep 5: Determine the combined weight of
luggage and cargo being loaded on the
vehicle. That weight may not safely exceed
the available cargo and luggage load capa-
city calculated in step 4.
Example: steps 1 to 3
The following table shows examples on how
to calculate total and cargo load capacities
with varying seating configurations and num-
ber and size of occupants. The following
examples use a 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
(
Ypage 319).
The greater the combined weight of the occu-
pants, the lower the maximum luggage load. Step 1
Example 1Example 2
Combined
maximum
weight of
occupants
and cargo
(data from the
Tire and Load-
ing Informa-
tion placard)1500 lbs
(680 kg)1500 lbs
(680 kg)
Step 2
Example 1Example 2
Number of
people in the
vehicle (driver
and occu-
pants)12
Weight of the
occupantsOccu-
pant 1:
175 lbs
(80 kg)Occu-
pant 1:
175 lbs
(80 kg)
Occu-
pant 2:
195 lbs
(88 kg)
Gross weight
of all occu-
pants175 lbs
(80 kg)370 lbs
(168 kg)
Loading the vehicle321
Wheels and tires
Z
Page 324 of 358

Step 3
Example 1Example 2
Permissible
load (maxi-
mum gross
vehicle weight
rating from
the Tire and
Loading Infor-
mation plac-
ard minus the
gross weight
of all occu-
pants)1500 lbs
(680 kg)Ò
175 lbs
(80 kg) =
1325 lbs
(600 kg)1500 lbs
(680 kg) Ò
370 lbs
(168 kg) =
1130 lbs
(512 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
(
Ypage 319).
Permissible gross vehicle weight: the
gross weight of the vehicle, all passengers
and the load must not exceed the permissible
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 and the load) weighed on a
suitable vehicle weighbridge.
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: treadwear 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.
Where applicable, the tire grading informa-
tion can be found on the tire sidewall between
the tread shoulder and maximum tire width.
Example:
RTreadwear grade: 200
RTraction grade:AA
RTemperature grade: A
All passenger car tires must conform to the
statutory safety requirements in addition to
these grades.
iThe actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
322All about wheels and tires
Wheels and tires
Page 325 of 358

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
GWARNING
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 (
Ypage 309). 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 tire
s (
M+S
tires) (
Ypage 310).
Temperature
GWARNING
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
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.
All about wheels an d tires323
Wheels and tires
Z
Page 326 of 358

Tire labeling
Overview
:Uniform Tire Quality Grading Standard
(
Ypage 328)
;DOT, Tire Identification Number
(
Ypage 327)
=Maximum tire load (Ypage 326)
?Maximum tire pressure (Ypage 314)
AManufacturer
BTire material (Ypage 327)
CTire size designation, load-bearing capa-
city and speed index (
Ypage 324)
DLoad index (Ypage 326)
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.
Height-width ratio: aspect ratio;is the
size ratio between the tire height and tire
width and is shown in percent. The aspect
324All about wheels an d tires
Wheels and tires
Page 327 of 358

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 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 on the driver's side (
Ypage 319).
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 326).
For further information on the load bearing
index, see "Load index" (
Ypage 326).
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.
Sum-
mer
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)
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 (300 km/h)
ZRover 149 mph (240 km/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 ZR18).
The service specification is made up of
load-bearing index Aand speed rating B.
RIf 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).
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
All about wheels and tires325
Wheels and tires
Z
Page 328 of 358

"(Y)" indicates that the maximum speed of
the tireisover 186 mph (300 km/h). Ask
the tire manufacturer about the maximum
speed.
All-
weather
tires
and win-
ter tires
IndexSpeed rating
Q M+S1up to 100 mph (160 km/h)
T M+S1up to 118 mph (190 km/h)
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 driv ing characteristics of winter tires. In
addit ion 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-
cial lydeveloped for driving on snow.
An electronic speed limiter prevents your
veh icle from exceeding the following speeds:
RAll veh icles (except Mercedes-AMG veh i-
cles): 130 mph (210 km/h)
RMercedes-AMG vehicles: 155 mph
(250 km/h)
RMercedes-AMG vehicles with Performance
Package: 174 mph (280 km/h)
The speed rating of tires mounted at the fac- tory may behigher 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 inthe "tires" section (
Ypage 335). Further information about reading tire data
can
beobtained from any qualified specialist
workshop.
Load index
In addition to the load bearing index, load rat-
ing :may beimprinted after the letters that
identify speed rating on the sidewall of the tire
(
Ypage 324).
RIf no specific ationisgiven: no text (as inthe
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
depe nds on the maximum load that the tire
can carry at a certain pressure
iTire data isveh icle-specific and may devi-
ate from the data inthe example.
Maximum load rating
1Or M+S ifor winte rtires.
326All about wheels and tires
Wheels and tires