Page 265 of 290

Overinflated tires may:
R
increase the braking distance
R adversely affect handling
R wear excessively and/or unevenly
R have an adverse effect on ride comfort
R be more susceptible to damage
Maximum tire pressures 0043
Example: maximum permissible tire pres-
sure
Never exceed the maximum permissible tire
inflation pressure. Always observe the recom-
mended tire pressure for your vehicle when
adjusting the tire pressure (Y page 260).
i The actual values for tires are vehicle-spe-
cific and may deviate from the values in the
illustration. Checking the tire pressures
Important safety notes Observe the notes on tire pressure
(Y
page 260).
Information on air pressure for the tires on your vehicle can be found:
R on the vehicle's Tire and Loading Information
placard on the B-pillar
R in the tire pressure table in the charge socket
flap (Y page 124)
R in the "Tire pressure" section Checking tire pressures manually To determine and set the correct tire pressure,
proceed as follows:
X Remove the valve cap of the tire that is to be
checked.
X Press the tire pressure gauge securely onto
the valve.
X Read the tire pressure and compare it to the
recommended value on the Tire and Loading
Information placard or the tire pressure table
(Y page 260).
X If the tire pressure is too low, increase the tire
pressure to the recommended value.
X If the tire pressure is too high, release air. To
do so, press down the metal pin in the valve,
using the tip of a pen for example. Then check the tire pressure again using the tire pressure
checker.
X Screw the valve cap onto the valve.
X Repeat these steps for the other tires. Tire pressure monitor
General notes If a tire pressure monitor is installed, the vehi-
cle's wheels have sensors that monitor the tire
pressures in all four tires. The tire pressure mon-
itor warns you if the pressure drops in one or
more of the tires. The tire pressure monitor only functions if the corresponding sensors are
installed in all wheels.
Information on tire pressures is displayed in the
multifunction display. After a few minutes of
driving, the current tire pressure of each tire is
shown in the Serv. Serv.menu of the multifunction
display, see illustration (example). For information on the message display, refer to
the "Checking the tire pressure electronically"
section (Y page 265). Tire pressure
263Wheels and tires Z
Page 266 of 290

Important safety notes
G
WARNING
Each tire, including the spare (if provided),
should be checked at least once every two
weeks when cold and inflated to the pressure recommended by the vehicle manufacturer
on the Tire and Loading Information placard
on the driver's door B-pillar or the tire pres-
sure label on the inside of the fuel filler flap. If
your vehicle has tires of a different size than
the size indicated on the Tire and Loading
Information placard or, if available, the tire
pressure label, you should determine the
proper tire pressure for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring system (TPMS) that illuminates a low tire pres-
sure telltale when one or more of your tires
are significantly underinflated. Accordingly,
when the low tire pressure telltale lights up,
you should stop and check your tires as soon
as possible, and inflate them to the proper
pressure. Driving on a significantly underin-
flated tire causes the tire to overheat and can
lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle's handling and stopping ability. Please note that the TPMS is not a substitute for proper tire
maintenance, and it is the driver's responsi-
bility to maintain correct tire pressure, even if
underinflation has not reached the level to
trigger illumination of the TPMS low tire pres-
sure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined with
the low tire pressure telltale. When the sys-
tem detects a malfunction, the warning lamp
will flash for approximately a minute and then remain continuously illuminated. This
sequence will be repeated every time the vehi- cle is started as long as the malfunction
exists. When the malfunction indicator is illu- minated, the system may not be able to detect
or signal low tire pressure as intended.
TPMS malfunctions may occur for a variety of reasons, including the installation of incom-
patible replacement or alternate tires or
wheels on the vehicle that prevent the TPMS
from functioning properly. Always check the
TPMS malfunction telltale after replacing one or more tires or wheels on your vehicle to
ensure that the replacement or alternate Tires and wheels allow the TPMS to continue to
function properly.
It is the driver's responsibility to set the tire
pressure to that recommended for cold tires
which is suitable for the operating situation
(Y page 260). Note that the correct tire pressure
for the current operating situation must first be taught-in to the tire pressure monitor. If a sub-
stantial loss of pressure occurs, the warning
threshold for the warning message is aligned to
the taught-in reference values. Restart the tire
pressure monitor after adjusting the pressure of the cold tires (Y page 265). The current pres-
sures are saved as new reference values. As a
result, a warning message will appear if the tire
pressure drops significantly.
The tire pressure monitor does not warn you of
an incorrectly set tire pressure. Observe the
notes on the recommended tire pressure
(Y page 260).
The tire pressure monitor is not able to warn you of a sudden loss of pressure, e.g. if the tire is
penetrated by a foreign object. In the event of a
sudden loss of pressure, bring the vehicle to a
halt by braking carefully. Avoid abrupt steering
movements.
The tire pressure monitor has a yellow warning
lamp in the instrument cluster for indicating
pressure loss or a malfunction. Whether the
warning lamp flashes or lights up indicates
whether a tire pressure is too low or the tire
pressure monitor is malfunctioning:
R if the warning lamp is lit continuously, the tire
pressure on one or more tires is significantly
too low. The tire pressure monitor is not mal- functioning.
R if the warning lamp flashes for around a
minute and then remains lit constantly, the
tire pressure monitor is malfunctioning.
In addition to the warning lamp, a message
appears in the multifunction display. Observe 264
Tire pressureWheels and ti
res
Page 267 of 290

the information on display messages
(Y page 185).
It may take up to ten minutes for a malfunction of the tire pressure monitor to be indicated. A
malfunction will be indicated by the tire pres-
sure warning lamp flashing for approximately
one minute and then remaining lit. When the
malfunction has been rectified, the tire pressure
warning lamp goes out after a few minutes of
driving.
The tire pressure values indicated by the on-
board computer may differ from those meas-
ured at a gas station with a pressure gauge. The
tire pressures shown by the on-board computer refer to those measured at sea level. At high
altitudes, the tire pressure 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 transmit-
ting equipment (e.g. radio headphones, two-way radios) that may be being operated in or near the vehicle.
Checking the tire pressure electroni-
cally X
Make sure that the SmartKey is in position 2
in the ignition lock (Y page 109).
X Press 0059or0065 on the steering wheel to
select the Serv. Serv.menu.
X Press the 0063or0064 button to select
Tire Pressure
Tire Pressure.
X Press the 0076button.
The current tire pressure of each tire is shown
in the multifunction display.
If the vehicle was parked for longer than
20 minute s,the Tire pressure will be Tire pressure will be
displayed after driving a few minutes
displayed after driving a few minutes
message is shown.
After a teach-in process, the tire pressure mon- itor automatically detects new wheels or new
sensors. As long as a clear allocation of the tire
pressure value to the individual wheels is not
possible, the Tire TirePressure
Pressure Monitor
Monitor Active
Active
message is shown instead of the tire pressure
display. The tire pressures are already being
monitored. Tire pressure monitor warning mes-
sages If the tire pressure monitor detects a pressure
loss in one or more tires, a warning message is
shown in the multifunction display. The yellow
tire pressure warning lamp then lights up.
R If the Please Correct Tire Pressure Please Correct Tire Pressure
message appears in the multifunction display, the tire pressure in at least one tire is too low.
The tire pressure must be corrected when the
opportunity arises.
R If the Check Tire Pressure
Check Tire Pressure message
appears in the multifunction display, the tire
pressure in one or more tires has dropped
significantly. The tires must be checked.
R If the Tire Tire Pressure
Pressure Warning
WarningTire
TireFail‐
Fail‐
ure
ure message appears, the tire pressure in one
or more tires has dropped suddenly. The tires
must be checked.
Observe the instructions and safety notes in the display messages in the "Tires" section
(Y page 185).
If the wheel positions on the vehicle are rotated,
the tire pressures may be displayed for the
wrong positions for a short time. This is rectified after a few minutes of driving, and the tire pres-
sures 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 cur-
rently set tire pressures as the reference values for monitoring. In most cases, the tire pressure
monitor will automatically detect the new refer-
ence values after you have changed the tire
pressure. However, you can also set 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 recommen-
ded for the corresponding driving situation on
the Tire and Loading Information placard on
the driver's side B-pillar (Y page 260).
Additional tire pressure for various operating
conditions can be found in the tire pressure
table in the charge socket flap (Y page 124).
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 (Y page 109). Tire pressure
265Wheels and tires Z
Page 268 of 290

X
Press 0059or0065 on the steering wheel to
select the Serv.
Serv.menu.
X Press the 0063or0064 button to select
Tire Pressure
Tire Pressure.
X Press the 0076button.
The multifunction display shows the current
tire pressure for each tire or the Tire pres‐
Tire pres‐
sure sure will
willbe
be displayed
displayed after
afterdriving
driving
a few minutes
a few minutes message.
X Press the 0064button.
The multifunction display shows the Use
Use
Current Pressures as New Reference
Current Pressures as New Reference
Values Values message.
If you wish to confirm the restart: X Press the 0076button.
The Tire
Tire Press.
Press. Monitor
Monitor Restarted
Restarted mes-
sage 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 pres-sures are then accepted as reference values
and monitored.
If you wish to cancel the restart:
X Press the 0038button.
The tire pressure values stored at the last
restart will continue to be monitored.
Radio type approval for the tire pres-
sure monitor Country Radio type approval number
USA FCC ID: MRXMW2433A
FCC ID: MRXGG4
FCC ID: MRXMC34MA4
Canada IC: 2546A-MW2433A
IC: 2546A-GG4
IC: 2546A-MC34MA4
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 Tireand Loading Information placard shows the
maximum permissible number of occu-
pants and the maximum permissible vehicle
load. It also contains details of the tire sizes
and corresponding pressures for tires
mounted at the factory.
(2) The vehicle identification plate is on the B- pillar on the driver's side. The vehicle iden-
tification plate informs you of the gross
vehicle weight rating. It is made up of the
vehicle weight, all vehicle occupants, the
fuel and the cargo. You can also find infor-
mation 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. 0043
B-pillar, driver's side 266
Loading the vehicleWheels and tires
Page 269 of 290

Maximum permissible gross vehicle
weight rating X
Specification for maximum gross vehicle
weight 0043is 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
0043indicates the
maximum number of occupants allowed to
travel in the vehicle. This information can be
found on the Tire and Loading Information plac-
ard.
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 pur-
suant to the "National Traffic and Motor Vehicle
Safety Act of 1966".
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 avail-
able amount of cargo and luggage load capa-
city. For example, if the "XXX" amount equals 1400 lbs and there will be five 150-lb pas-
sengers in your vehicle, the amount of avail-
able 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 vehi-
cle. That weight may not safely exceed the
available cargo and luggage load capacity cal- culated 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 Loading the vehicle
267Wheels and tires Z
Page 270 of 290

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 266).
The greater the combined weight of the occupants, the lower the maximum luggage load.
Step 1 Example 1 Example 2 Example 3
Combined maximum
weight of occupants
and cargo (data from
the Tire and Loading
Information placard)
1500 lbs (680 kg) 1500 lbs (680 kg) 1500 lbs (680 kg)
Step 2
Example 1 Example 2 Example 3
Number of people in
the vehicle (driver and
occupants)
5 3 1
Distribution of the
occupants
Front: 2
Rear: 3 Front: 1
Rear: 2 Front: 1
Weight of the occu-
pants
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) Occupant 1: 200 lbs
(91 kg)
Occupant 2: 190 lbs
(86 kg)
Occupant 3: 150 lbs
(68 kg) Occupant 1: 150 lbs
(68 kg)
Gross weight of all
occupants
750 lbs (340 kg) 540 lbs (245 kg) 150 lbs (68 kg)
Step 3
Example 1 Example 2 Example 3
Permissible load (maxi-
mum gross vehicle
weight rating from the
Tire and Loading Infor-
mation placard minus
the gross weight of all
occupants)
1500 lbs (680 kg)
00F8
750 lbs (340 kg) =
750 lbs (340 kg) 1500 lbs (680 kg)
00F8
540 lbs (245 kg)
=960 lbs (435 kg) 1500 lbs (680 kg)
00F8
150 lbs (68 kg) =
1350 lbs (612 kg) Vehicle identification plate
Even if you have calculated the total cargo care-
fully, 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 266).268
Loading the vehicleWheels and tires
Page 271 of 290

Permissible Gross Vehicle Weight Rating
(GVWR): the gross weight of the vehicle, all pas-
sengers, load and trailer load/noseweight (if
applicable) must not exceed the permissible
gross vehicle weight.
Gross Axle Weight Rating (GAWR): the maxi-
mum permissible weight that can be carried by
one axle (front or rear axle).
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, occu- pants, cargo, and full trailer load if applicable)
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 purpose is to
provide drivers with uniform reliable information
on tire performance data. Tire manufacturers
have to grade tires using three performance fac-
tors: 0043tread wear grade, 0044traction grade and
0087 temperature grade. These regulations do not
apply to Canada. Nevertheless, all tires sold in
North America are provided with the corre-
sponding quality grading markings on the side-
wall of the tire.
Quality grades can be found, where applicable,
on the tire sidewall between tread shoulder and maximum section width. Example:
R Treadwear grade: 200
R Traction grade: AA
R Temperature grade: A
All passenger car tires must conform to the stat-
utory safety requirements in addition to these
grades.
i The actual values for tires are vehicle-spe-
cific 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 cli-
mate.
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 meas-
ured under controlled conditions on specified
government test surfaces of asphalt and con-
crete. 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 condi-
tions when temperatures are around freezing
point.
Mercedes-Benz recommends a minimum tread
depth of 00CFin (4 mm) on all four winter tires. All about wheels and tires
269Wheels and tires Z
Page 272 of 290

Observe the legally required minimum tire tread
depth (Y page 258). Winter tires can reduce the
braking distance on snow-covered surfaces in
comparison with summer tires. The braking dis-
tance is still much further than on surfaces that
are not icy or covered with snow. Take appro-
priate care when driving.
Further information on winter tires (M+S tires)
(Y page 259).
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, representing 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. Sus- tained 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 0043
Uniform Tire Quality Grading Standards
(Ypage 274)
0044 Department of Transportation, Tire Identifi-
cation Number (Y page 273)
0087 Maximum load rating (Y page 272)
0085 Maximum tire pressures (Y page 263)
0083 Manufacturer
0084 Tire material (Y page 273)
006B Tire size designation, load-bearing capacity
and speed rating (Y page 270)
006C Load index (Y page 272)
006D 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 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 270
All about wheels and tiresWheels and tires