Important notes on tire pressure
GWARNING
If th etire pressur edrops repeatedly, th e
wheel, valv eor tire may be damaged. Tir e
pressur ethat is to olow may result in atire
blow-out .Ther eis aris kof an accident.
RChec kth etire for foreign objects .
RCheckwhether th ewhee lis losing air or th e
valv eis leaking .
If you are unable to rectify th edamage, con-
tac t a qualified specialist workshop.
Use asuitable pressur egage to chec kth etire
pressure. The outer appearanc eof atire does
no tpermit any reliable conclusio nabout th etire
pressure. On vehicles equipped wit hth eelec -
tronic tire pressur emonitor, th etire pressur e
can be checke dusin gth eon-board computer.
The tire temperature and pressur eincreas e
when th evehicl eis in motion .This is dependen t
on th edriving spee dand th eload.
Therefore, you should only correc ttire pressur e
when th etires are cold.
The tires are cold:
Rif th evehicl ehas been parked for at least
three hour swithout direct sunligh ton th e
tires ,and
Rif th evehicl ehas no tbeen driven further than
1 mile (1.6 km )
Tire temper ature changes depending on the
ambient temperature, driving speed and tire
load. If the tire temperature changes by 18 ‡
(10 †), the tire pressure ch anges by approx
-
imately 10 kPa (0.1 bar/1.5 psi). Take this into
account when checking the pressure of warm
tires. Only correct the tire pressure if it is too low
for the current operating conditions. If you
check the tire pressure when the tires are warm,
it results in a higher value than when the tires
are cold. This is normal. Do not under any cir-
cumstances release the air in order to adjust the
pressure to the prescribed value for cold tires.
The tire pressure would otherwise be too low.
Observe the recommended tire pressure for
cold tires on the tire pressure table in the fuel
filler flap. Driving with tire pressure that is too high or too
low can:
Rshorten the service life of the tires
Rcause increased tire damage
Rhave a negative effect on handling character-
istics and thus the driving safety (e.g. hydro-
planing)
Underinflated or overinflated tires
Underinflated tires:
GWARNING
Tires with pressure that is too low can over-
heat and burst as a consequence. In addition, they also suffer from excessive and/or irreg-
ular wear, which can severely impair the brak-
ing properties and the driving characteristics.
There is a risk of an accident.
Avoid tire pressures that are too low in all the
tires, including the spare wheel.
Underinflated tires can:
Rfail from being overheated
Radversely affect handling
Rwear excessively and/or unevenly
Rhave an adverse effect on fuel consumption
Overinflated tires
GWARNING
Tires with excessively high pressure can burst
because they are damaged more easily by
road debris, potholes etc. In addition, they
also suffer from irregular wear, which can
severely impair the braking properties and the driving characteristics. There is a risk of an
accident.
Avoid tire pressures that are too high in all the
tires, including the spare wheel.
Overinflated tires can:
Rincrease the braking distance
Radversely affect handling
Rwear excessively and/or unevenly
Radversely affect ride comfort
Rbe more susceptible to damage
Tire pressure283
Wheels and tires
Z
Maximum tire pressures
:Maximum permitted tire pressure (example)
Never exceed the maximum permissible tire
inflation pressure. When adjusting the tire pres-
sures always observe the recommended tire
pressure for your vehicle (
Ypage 280).
iThe actual values for tires are specific to
each vehicle and may deviate from the values
in the illustration.
Tire valve (snap-in valve)
Important safety notes
GWARNING
Tire valve that are not approved for your vehi-
cle by the distributor named on the inside
cover page may result in a loss of tire pres-
sure. This may affect road safety. There is a
risk of an accident.
Only use tire valve that are approved for your
vehicle by the distributor named on the inside
cover page. Always make sure you have the
correct tire valve type for the tires on your
vehicle.
!Do not screw additional weights (check
valves, etc.) onto the tire valves. The elec-
tronic components could thus be damaged.
iFor safety reasons, Mercedes-Benz recom-
mends that you only use tire valves that have been tested for use on your vehicle.
Checking the tire pressure manually
In order to determine and adjust the tire pres-
sures, proceed as follows:
XRemove the valve cap of the tire you wish to
check.
XPress the tire pressure gauge securely onto
the valve.
XRead the tire pressure and compare it with the
recommended value on the loading informa-
tion table or the tire pressure table
(
Ypage 280).
XIf the tire pressure is too low, increase it to the
recommended value.
XIf the tire pressure is too high, release air by
pressing down the metal pin in the valve. Use
the tip of a pen, for example. Then, check the
tire pressure again using the tire pressure
gauge.
XScrew the valve cap onto the valve.
XRepeat the steps for the other tires.
Tire pressure monitor
General notes
In vehicles with a tire pressure monitor system,
the vehicle's wheels have sensors installed
which monitor the tire pressure in all four tires.
The tire pressure monitor warns you if the pres- sure drops in one or more of the tires. The tire
pressure monitor only functions if the corre-
sponding sensors are installed on all wheels.
Tire pressure display (only on vehicles with steer-
ing wheel buttons)
On vehicles with steering wheel buttons, the
current pressure of the individual tires can be
shown in the display using the Service
menu.
284Tire pressure
Wheels and tires
For further information on displaying the current
tire pressures, refer to "Checking the tire pres-
sure electronically" (
Ypage 286).
Important safety notes
GWARNING
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the pressure rec-
ommended by the vehicle manufacturer on
the Tire and Loading Information placard on
the driver's door B-pillar or the tire pressure
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 Infor-
mation placard or 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 illuminates,
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 stop-
ping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the driv-
er's responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level to trigger illumination of the
TPMS low tire pressure telltale.
USA only:
Your vehicle has al so b
een equipped with a
TPMS malfunction indicator to indicate if the
system is not operating properly. The TPMS
malfunction indicator is combined with the
low tire pressure telltale. When the system
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 illuminated,
the system may not be able to detect or signal
low tire pressure as intended. TPMS malfunc-
tions may occur for a variety of reasons,
including the mounting of incompatible
replacement or alternate tires or wheels on
the vehicle that prevent the TPMS from func-
tioning properly. Always check the TPMS mal-
function 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 prop-
erly.
It is the driver's responsibility to set the tire
pressure to the recommended cold tire pressure
suitable for the operating conditions
(
Ypage 280).
Note that the correct tire pressure for the cur-
rent operating conditions must first be pro-
gramed into the tire pressure monitor. If there is
a substantial loss of pressure, the warning
threshold for the warning message is aligned to
the reference values programed in. Restart the
tire pressure monitor after adjusting the cold
tire pressure (
Ypage 287). The current pres-
sures are saved as new reference values. This
will ensure that a warning message will only
appear if the tire pressure drops significantly.
The tire pressure monitor does not warn you if a
tire pressure is incorrect. Obs erve the note
s on
the recommended tire pressure (Ypage 280).
The tire pressure monitor is not able to warn you
of a sudden loss of pressure, e.g. following pen- etration by a foreign object. In this event, brake
the vehicle until it comes to a standstill. Avoid
sudden steering movements.
The tire pressure monitor has a yellow h
warning lamp in the instrument cluster for indi-
cating pressure loss/malfunctions (USA) or
pressure loss (Canada). Depending on how the
warning lamp flashes or lights up, an underin-
flated tire or a malfunction in the tire pressure
monitor is displayed:
Rif the h warning lamp is lit continuously,
the tire pressure on one or more tires is sig-
Tire pressure285
Wheels and tires
Z
nificantly too low. The tire pressure monitor is
not malfunctioning.
RUSA only: if thehwarning lamp flashes for
60 seconds and then remains lit constantly,
the tire pressure monitor is malfunctioning.
The display also shows a message:
Ron vehicles without steering wheel buttons
(Ypage 201)
Ron vehicles with steering wheel buttons
(Ypage 217)
USA only: if the tire pressure monitor is mal-
functioning, it may be more than ten minutes
before the malfunction is shown. The htire
pressure warning lamp flashes for 60 seconds
and then remains lit. When the malfunction has
been rectified, the htire 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 gage. 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 gage are higher than those shown by
the on-board computer. In this case, do not
reduce the tire pressures.
If radio transmitting equipment (e.g. wireless
headphones, two-way radios) is operated inside
the vehicle or in the vicinity of the vehicle, this
can interfere with the operati
on of the tire pres-
sure monitor.
Checking the tire pressure electroni-
cally on vehicles with steering wheel
buttons
You can only check the tire pressure electroni-
cally on vehicles with steering wheel buttons.
Using the steering wheel buttons
XTurn the key to position 2in the ignition lock.
XPress the =or; button to select the
Servicemenu.
XUse the 9or: button to select TirePressure.
XPressato confirm.
The current tire pressure of each wheel is
shown in the display.
If the vehicle has been parked for over
20 minutes, the Tire pressure will be
displayed after driving a few minutesmessage appears. After a teach-in period, the tire pressure monitor
automatically detects new wheels or new sen-
sors. As long as a clear allocation of the tire
pressure value to the individual wheels is not
possible, the
Tire
PressureMonitorActivemessage 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 loss in
pressure in one or more tires, a warning mes-
sage is shown in the display. The hwarning
lamp lights up.
Vehicles without steering wheel buttons
RIf the Correct Tire Pressuremessage is
shown in the display, the tire pressure in at
least one tire is too low. The tire pressure
must be corrected at the next opportunity.
RIf the CheckTirePressureSoonmessage
is shown in the display, the tire pressure in
one or more tires has dropped significantly.
The tires must be checked.
RIf the Warning Tire Malfunc.message is
shown in the display, the tire pressure in one
or more tires has dropped suddenly. The tires
must be checked.
Vehicles with steering wheel buttons
RIf the Adjust Tire Pressuremessage is
shown in the display, the tire pressure in at
least one tire is too low. The tire pressure
must be corrected at the next opportunity.
RIf the Check Tiresmessage is shown in the
display, the tire pressure in one or more tires has dropped significantly. The tires must be
checked.
RIf the WarningTireMalfunctionmessage
is shown in the display, the tire pressure in
one or more tires has dropped suddenly. The
tires must be checked.
Always read and follow the instructions and
safety notes related to the display messages,
which can be found in the "Tires" section.
Rfor vehicles without steering wheel buttons
(Ypage 201)
Rfor vehicles with steering wheel buttons
(Ypage 217)
Vehicles with steering wheel buttons: if the
wheel positions on the vehicle are rotated, the
tire pressures may be displayed for the wrong
286Tire pressure
Wheels and tires
positions for a short time. This is rectified after a
few minutes of driving; the tire pressures are
then displayed for the correct positions.
Restarting the tire pressure monitor
General notes
When you restart the tire pressure monitor, all
existing warning messages are deleted and the
warning lamp goes out. The monitor uses the
currently set tire pressures as the reference val-
ues for monitoring. In most cases, the tire pres-
sure monitor will automatically detect the new
reference values after you have changed the tire
pressures. However, you can also define refer-
ence values manually as described here. The tire
pressure monitor then monitors the new tire
pressure values.
Vehicles without steering wheel buttons
The vehicle must be stationary. Use the buttons
in the instrument cluster.
XTurn the key to position 2in the ignition lock.
XPress Èto select the TirePressuremenu.
XPress3to confirm.
The display shows the Monitoring Active
message.
XPress3to confirm.
The display shows the Tire Pressure OK?
message.
If you wish to confirm the restart:
XPress the fbutton.
The display shows the distance menu.
After you have driven for a few minutes, the
system checks whether the current tire pres-
sures are within the specified range. The new
tire pressures are then accepted as reference
values and are monitored.
If you wish to cancel the restart:
XPress g.
The display shows the tire pressure menu.
The tire pressure values stored at the last
restart will continue to be monitored.
Vehicles with steering wheel buttons
Using the steering wheel buttons
XMake sure that the tire pressure of all four
wheels is set correctly for the current oper-
ating conditions. When doing so, observe the
notes under "Tire pressure" (
Ypage 280).
XTurn the key to position 2in the ignition lock.
XPress =or; to select the Servicemenu.
XPress9or: to select the TirePres‐suresubmenu.
XPressato confirm.
The display shows either the current tire pres-
sure for the individual tires, or the Tire
pressure will be displayed afterdriving a few minutesmessage.
XPress the:button.
The display shows the Use Current Pres‐
sures as New Reference Values:mes-
sage.
If you wish to confirm the restart:
XPress the abutton.
The display shows the Tire Press. Moni‐
tor Restartedmessage.
After you have driven for a few minutes, the
system checks whether the current tire pres- sures are within the specified range. The new
tire pressures are then accepted as reference
values and are 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.
Tire pressure287
Wheels and tires
Z
Tire pressure tables
Vehicles with a gross vehicle weight of 6,724 lbs (3.05 t)
!The pressure difference between tires on any one axle must be no greater than 10 kPa (0.1 ba r/
1.5 psi).
The following tire pressure values apply to vehicles with:
Ra gross vehicle weight of 6,724 lbs (3.05 t)
Ra gross axle weight rating of 3,418 lbs(1,550 kg)on the rear axle and
Rthe tires referred to under "Wheel and tire combinations" (Ypage 300)
Always observe the notes under "Information on tire pressures" (
Ypage 280).
The tire pressure for the spare wheelis 340 kPa (3.4 bar/49 psi).
Partially laden vehicleFully laden vehicle
Tire sizeFront axleRear axleFront axleRear axle
225/55 R 17 XL270 kPa
(2.7 bar/ 39 psi)270 kPa
(2.7 bar/ 39 psi)300 kPa
(3.0 bar/ 44 psi)310 kPa
(3.1 bar/45 psi)
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.
Example: Tire and Loading Information placard on
the B-pillar, driver's side
Two instruction labels on your vehicle show themaximum possible load.
(1) Tire and Loading Information placard :is
on the B-pillar on the driver's side. Tire and
Loading Information placard :shows the
permissible number of occupants and the
maximum permissible load of the vehicle. 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
identification plate informs you of the per-
missible gross weight. 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). Do not exceed the permissible gross weight or the maxi-
mum gross axle weight rating for the front
or rear axle.
288Loading the vehicle
Wheels and tires
Vehicle identification plate
Even if you have calculated the total load care-
fully, you should still make sure that the permis-
sible gross weight and the gross axle weight rat-
ing of your vehicle are not exceeded. This data
can be found on the vehicle identification plate
on the B-pillar of your vehicle (
Ypage 303).
Permissible gross vehicle weight: the gross
weight of the vehicle, all occupants, load and
trailer load/noseweight (if applicable) must not
exceed the permissible gross vehicle weight.
Gross axle weight rating: the maximum per-
missible load 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, 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 approximately 10%
of the gross weight of the trailer and its load.
What you should know about wheels
and tires
Tire labeling
Tire labeling
:DOT, Tire Identification Number
(Ypage 293)
;Maximum tire load (Ypage 293)
=Maximum tire pressure (Ypage 284)
?Manufacturer
ATire material (Ypage 294)
BTire size designation, load-bearing capacity
and speed index (Ypage 291)
CTire name
The markings described above are on the tire in
addition to the tire name (sales designation) and
the manufacturer's name.
iTire data is vehicle-specific and may deviate
from the data in the example.
Tire size designation, load bearing index
and speed index
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
What you should know about wheels and tires291
Wheels and tires
Z
Load index
Load index (example)
In addition to the load-bearing index, load rat-
ing:may be imprinted after the letters that
identify speed rating on the sidewall of the tire
(
Ypage 291).
RIf no specification is given: no text (as in the
example above), represents a standard load
(SL) tire
RRF or Reinforced: represents a reinforced tire.
Alternatively, depending on the manufac-
turer, the designation XL (Extra Load) can be
used.
RLight Load: represents a light load tire
RC, D, E: represents a load range that depends
on the maximum load that the tire can carry at
a certain pressure
iTire data is vehicle-specific and may deviate
from the data in the example.
Maximum tire load
Example: maximum tire load
Maximum tire load :is the maximum permis-
sible weight for which the tire is approved.
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 (
Ypage 288).
iThe actual values for tires are specific to
each vehicle and may deviate from the values
in the illustration.
DOT, Tire Identification Number (TIN)
U.S. 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 retreaders
to inform purchasers of recalls and other safety-
relevant matters. It makes it possible for the
purchaser to easily identify the affected tires.
The TIN is made up of manufacturer identifica-
tion 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: manufac-
turer identification code ;provides details on
the tire manufacturer. New tires have a code
with two symbols. Retreaded tires have a code
with four symbols.
Further information about retreaded tires
(
Ypage 277).
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 manufactureA
provides information about the age of a tire. The first and second positions represent the week of
manufacture, starting with "01" for the first cal-
endar week. Positions three and four represent
What you should know about wheels and tires293
Wheels and tires
Z