values indicated by a pressure gauge are
higher than those shown by the on-board
computer.
In this case, do not reduce the tire
pressures.
The operation of the tire pressure monitor can
be affected by interference from radio
transmitting equipment (e.g. radio
headphones, two-way radios) that may be
being operated in or near the vehicle.
i USA only:
This device complies with part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause interference,
and
2. this device must accept any interference
received, including interference that may
cause undesired operation of the device.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
i Canada only:
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause interference,
and
2. this device must accept any interference
received, including interference that may
cause undesired operation.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
Checking tire pressure electronically X
Make sure that the SmartKey is in
position 2 (Y
page 153) in the ignition lock.
X Press the = or ; button on the
steering wheel to select the Serv. menu. X
Press the 9 or : button to select
Tire Pressure.
X Press button a.
The
current tire pressure for each wheel will
be displayed in the multifunction display.
If the vehicle was parked for longer than
20 minutes the Tire pressures will be
displayed after driving a few
minutes message is shown.
After a teach-in period, the tire pressure
monitor
automatically recognizes new wheels
or new sensors. If a clear allocation of the tire
pressure values to the individual wheels is not
possible, the message is shown instead of the
tire pressure display. The tire pressures are
already being monitored.
i If an emergency spare wheel is mounted,
the system may continue to show the tire
pressure of the wheel that has been
removed for a few minutes. If this occurs,
note that the value displayed for the
position where the spare wheel is mounted
is not the same as the current tire pressure
of the emergency spare wheel.
Tire pressure monitor warning
messages If the tire pressure monitor detects a
significant
pressure loss on one or more tires,
a warning message is shown in the
multifunction display. A warning tone also
sounds and the tire pressure warning lamp
lights up in the instrument cluster.
Each tire that is affected by a significant loss
of pressure is highlighted in the pressure
display.
X If the Correct Tire Pressure message
appears
in the multifunction display, check
the tire pressure on all four wheels and
correct it if necessary.
i If the wheel positions on the vehicle are
interchanged, the tire pressures may be
displayed for the wrong positions for a
short time. This is rectified after a few 372
Tire pressure
Wheels and tires
minutes of driving, and the tire pressures
are displayed for the correct positions.
Restarting the tire pressure monitor When you restart the tire pressure monitor,
all
existing warning messages are deleted and
the warning lamps go out. The monitor uses
the currently set tire pressures as the
reference values for monitoring. In most
cases, the tire pressure monitor will
automatically detect the new reference
values after you 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.
X Set the tire pressure to the value
recommended for the corresponding
driving situation on the Tire and Loading
Information placard on the driver's side
B-pillar ( Y page 366).
Additional
tire pressure values for different
loads can also be found on the tire pressure
table on the inside of the fuel filler flap
(Y page 366).
X Make sure that the tire pressure is correct
on all four wheels.
X Make sure that the SmartKey is in position
2 in the ignition lock.
X Press the = or ; button on the
steering wheel to select the Serv. menu.
X Press the 9 or : button to select
Tire Pressure.
X Press the a button.
The multifunction display shows the
current tire pressure for each tire or the
Tire pressures displayed after
driving a few minutes message.
X Press the : button.
The multifunction display shows the Use
Current Pressure Values as New
Reference Values message. If you wish to confirm the restart:
X
Press the a button.
The Tire Pressure Monitor
Restarted message appears in the
multifunction display.
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:
X Press the % button.
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
permissible vehicle load. It also contains
details of the tire sizes and
corresponding pressures for tires
installed 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 Loading the vehicle
373
Wheels and tires Z
occupants, 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
maximum gross axle weight rating for the
front or rear axle. B-pillar (example: Sedan)
Maximum permissible gross vehicle
weight rating
X
Specification 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
specified value. i
The specifications shown on the Tire and
Loading Information placard in the
illustration are examples. The maximum
permissible 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 Information 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.
i The specifications shown on the Tire and
Loading Information placard in the
illustration 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
Loading 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".374
Loading the vehicle
Wheels and tires
X
Step 1: Locate the statement "The
combined weight of occupants and cargo
should
never exceed XXX kg or XXX lbs." on
your vehicle’s Tire and Loading Information
placard.
X Step 2:
Determine the combined weight of
the driver and passengers that will be riding
in your vehicle.
X Step 3: Subtract the combined weight of
the driver and passengers from XXX
kilograms or XXX lbs.
X Step 4: The resulting figure equals the
available
amount of cargo and luggage load
capacity. For example: at a sum “XXX” of
1400 lbs and five occupants each weighing
150 lbs, the amount of available cargo and
luggage load capacity is 650 lbs (1400 -
750 (5 x 150) = 650 lbs).
X Step 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
capacity 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
number 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
(Y page 373).
The higher the weight of all the occupants, the
smaller the maximum load for luggage. Step 1 Exampl
e 1 Exampl
e 2 Exampl
e 3
Combin
ed
maximu
m
weight
of
occupa
nts and
cargo
(data
from
the Tire
and
Loading
Informa
tion
placard)
1500 lbs
(680 kg) 1500 lbs
(680 kg) 1500 lbs
(680 kg)
Step 2
Exampl
e 1 Exampl
e 2 Exampl
e 3
Number
of
people
in the
vehicle
(driver
and
occupa
nts)
5 3 1
Distribu
tion of
the
occupa
nts
Front: 2
Rear: 3 Front: 1
Rear: 2 Front: 1Loading the vehicle
375
Wheels and tires Z
Exampl
e 1 Exampl
e 2 Exampl
e 3
Weight
of the
occupa
nts
Occupan
t 1:
150 lbs
(68 kg)
Occupan
t 2:
180 lbs
(82 kg)
Occupan
t 3:
160 lbs
(73 kg)
Occupan
t 4:
140 lbs
(63 kg)
Occupan
t 5:
120 lbs
(54 kg) Occupan
t 1:
200 lbs
(91 kg)
Occupan
t 2:
190 lbs
(86 kg)
Occupan
t 3:
150 lbs
(68 kg) Occupan
t 1:
150 lbs
(68 kg)
Gross
weight
of all
occupa
nts
750 lbs
(340 kg) 540 lbs
(245 kg) 150 lbs
(68 kg) Step 3
Exampl
e 1 Exampl
e 2 Exampl
e 3
Permiss
ible
load
(maxim
um
gross
vehicle
weight
rating
from
the Tire
and
Loading
Informa
tion
placard
minus
the
gross
weight
of all
occupa
nts)
1500 lbs
(680 kg)
Ò750 lbs
(340 kg)
=
750 lbs
(340 kg) 1500 lbs
(680 kg)
Ò540 lbs
(245 kg)
=
960 lbs
(435 kg) 1500 lbs
(680 kg)
Ò150 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 373).
Permissible gross vehicle weight: the
gross weight of the vehicle, all passengers,
load and trailer load/noseweight (if
applicable) must not exceed the permissible
gross vehicle weight.
Gross axle weight rating: the maximum
permissible weight that can be carried by one
axle (front or rear axle). 376
Loading the vehicle
Wheels and tires
To ensure that your vehicle does not exceed
the maximum permissible values (gross
vehicle 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.
All about wheels and tires
Uniform Tire Quality Grading
Standards
Overview of Tire Quality Grading
Standards Uniform Tire Quality Grading Standards are
U.S. government specifications. Their
purpose is to provide drivers with uniform
reliable
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.
Where applicable, the tire grading
information 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 course as a
tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm, due to variations in driving habits,
service practices and differences in road
characteristics 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,
cornering, hydroplaning, or peak traction
characteristics.
! 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
surfaces.
You should pay special attention to road
conditions when temperatures are around
freezing point. All about wheels and tires
377Wheels and tires Z
Mercedes-Benz recommends a minimum
tread
depth of ã in (4 mm) on all four winter
tires. Observe the legally required minimum
tire tread depth (Y page 363). 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 364).
Temperature G
WARNING
The temperature grade for this tire is
established for a tire that is properly inflated
and not overloaded. Excessive speed,
underinflation, 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 dissipate 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 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
(Y page 382)
; DOT, Tire Identification Number
(Y page 381)
= Maximum tire load ( Y page 381)
? Maximum tire pressure (Y page 368)
A Manufacturer
B Tire material ( Y page 382)
C Tire size designation, load-bearing
capacity and speed index
(Y page 378)
D Load index ( Y page 381)
E Tire name
The markings described above are on the tire
in addition to the tire name (sales
designation) and the manufacturer's name.
i Tire data is vehicle-specific and may
deviate from the data in the example.
Tire size designation, load-bearing
capacity and speed rating G
WARNING
Exceeding the stated tire load-bearing
capacity and the approved maximum speed
could
lead to tire damage or the tire bursting.
There is a risk of accident. 378
All about wheels and tires
Wheels and tires
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
description (as shown above): these are
passenger vehicle tires according to
European manufacturing 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.
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: aspect ratio ; is the
size ratio between the tire height and tire
width and is shown in percent. The aspect 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 a “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: load-bearing index A
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 373).
Example:
The load bearing index 91 is equivalent to a
maximum load of 1356 lb (615 kg) that the
tire can carry. For further information on the
maximum tire load in kilograms and lbs, see
(Y page 381).
For further information on the load bearing
index, see "Load index" ( Y page 381).
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.
Summer tires Index Speed rating
Q up to 100 mph (160 km/h)
R up to 106 mph (170 km/h)All about wheels and tires
379
Wheels and tires Z