338 OperationTires and wheelsDirection of rotation
Unidirectional tires offer added advantag-
es, such as better hydroplaning perfor-
mance. To benefit, however, you must
make sure the tires rotate in the direction
specified.
An arrow on the sidewall indicates the
intended direction of rotation (spinning) of
the tire.
Loading the vehicle
Two labels on your vehicle show how much
weight it may properly carry.
The Tire and Loading Information
placard (Example A) or the Vehicle Tire
Information placard (Example B) can be
found on the driver’s door B-pillar. This
placard tells you important information
about the number of people that can be
in the vehicle and the total weight that
can be carried in the vehicle. It also
contains information on the proper size
and recommended tire inflation
pressures for the original equipment
tires on your vehicle.
The Certification label, also found on
the driver’s door B-pillar tells you about
the gross weight capacity of your vehi-
cle, called the Gross Vehicle Weight
Rating (GVWR). The GVWR includes the
weight of the vehicle, all occupants,
fuel and cargo. The Certification label
also tells you about the front and rear
axle weight capacity, called the Gross
Axle Weight Rating (GAWR). The GAWR
is the total allowable weight that can be
carried by a single axle (front or rear).
Never exceed the GVWR or GAWR for
either the front axle or rear axle.
iSpare wheels may be mounted against
the direction of rotation (spinning) even
with a unidirectional tire for temporary
use only until the regular drive wheel
has been repaired or replaced. Always
observe and follow applicable tempo-
rary use restrictions and speed limita-
tions indicated on the spare wheel.
348 OperationTires and wheels
Install the valve cap.
Repeat this procedure for each tire.Run Flat Indicator
While the vehicle is being driven, the Run
Flat Indicator monitors the set tire inflation
pressures by evaluating each wheel’s rota-
tional speed. This allows the system to de-
tect a significant loss of pressure in a tire.
If a wheel’s rotational speed changes due
to falling tire inflation pressure, you will
see a corresponding warning message in
the multifunction display.
The Run Flat Indicator may function in a re-
stricted manner or with a delay if:
snow chains are mounted to the
vehicle
winter road conditions prevail
you are driving on a loose surface (e.g.
sand or gravel)
you are driving in a very sporty manner
(involving rapid acceleration or high
speeds in curves)
iIf you have overfilled the tire, release
tire inflation pressure by pushing the
metal stem of the valve with e.g. a tip of
a pen. Then recheck the tire inflation
pressure with the tire gauge.
Warning!
G
When the multifunction display shows the
message
Tire pressure Check tires
,
one or more of your tires is significantly un-
der-inflated. You should stop and check
your tires as soon as possible, and inflate
them to the proper tire inflation pressure as
indicated on the vehicle’s tire information
placard. Driving on a significantly under-in-
flated tire causes the tire to overheat and
can lead to tire failure. Under-inflation also
reduces fuel efficiency and tire tread life,
and may affect the vehicle’s handling and
stopping ability. Each tire, including the
spare, should be checked monthly when
cold and set to the recommended tire infla-
tion pressure as specified in the vehicle
placard and owner’s manual.
351 Operation
Tires and wheels
Checking tire pressure electronically
with the Advanced Tire Pressure Moni-
toring System* (Advanced TPMS*)The TPMS only functions on wheels that
are equipped with the proper electronic
sensors. It monitors the tire inflation pres-
sure, as selected by the driver, in all four
tires. A warning is issued to alert you to a
decrease in pressure in one or more of the
tires.
Tire pressure inquiries are made using the
multifunction display.The present inflation
pressures are displayed only after a few
minutes’ travel time.
Switch on the ignition (
page 34).
Press thej or kbutton until
the current inflation pressures for each
tire appear in the multifunction display.
iThe Advanced T
ire P
ressure M
onitoring
S
ystem* (Advanced TPMS*) is
equipped with a combination low tire
pressure/TPMS malfunction telltale in
the instrument cluster (
page 24). De-
pending on how the telltale illuminates,
it indicates a low tire pressure condi-
tion or a malfunction in the TPMS sys-
tem itself:
If the telltale illuminates continu-
ously, one or more of your tires is
significantly under-inflated. There is
no malfunction in the TPMS.
If the telltale flashes for 60 seconds
and then stays illuminated, the
TPMS system itself is not operating
properly.
iPossible differences between the read-
ings of a tire pressure gauge of an air
hose, e.g. gas station equipment, and
the vehicle’s control system can occur.
Usually the readings issued by the con-
trol system are more precise.
iWhen the message
Tire pressure
display appears after driving sev-
eral minutes
appears in the display,
the individual inflation pressure values
are matched with the tires. The individ-
ual values are displayed after a few
minutes driving.
iWith a spare wheel without wheel sen-
sor mounted, the system may still indi-
cate the tire inflation pressure of the
removed wheel for some minutes. If
this happens, keep in mind that the in-
dicated value where the spare wheel is
mounted does not reflect the actual
spare tire inflation pressure.
352 OperationTires and wheelsWarning!
G
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust tire inflation pressure according to
the placard on the driver’s door B-pillar or, if
available, the supplemental tire pressure in-
formation on the inside of the fuel filler flap.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of pressure (e.g.
tire blowout caused by a foreign object). In
this case bring the vehicle to a halt by care-
fully applying the brakes and avoiding
abrupt steering maneuvers.
Warning!
G
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
vehicle placard or the tire inflation pressure
label. (If your vehicle has tires of a different
size than the size indicated on the vehicle
placard or the tire inflation pressure label,
you should consult the appropriate section
of this owner’s manual to determine the
proper tire inflation pressure). When the low
tire pressure telltale is illuminated, one or
more of your tires is significantly under-in-
flated. You should stop and check your tires
as soon as possible, and inflate them to the
proper pressure. Driving on a significantly
under-inflated tire causes the tire to over-
heat and can lead to tire failure. Under-infla-
tion also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s han-
dling and stopping ability.
Your vehicle has also been equipped with a
TPMS malfunction telltale to indicate when
the system is not operating properly. When
the malfunction telltale is illuminated, the
system may not be able to detect or signal
low tire pressure as intended. TPMS mal-
functions may occur for a variety of reasons,
including the installation of incompatible
replacement tires on the vehicle. Always
check the TPMS malfunction telltale after
replacing one or more tires on your vehicle
to ensure that the replacement tires are
compatible with the TPMS.
356 OperationTires and wheelsGeneral:
Depending on the design standards used,
the tire size molded into the sidewall may
have no letter or a letter preceding the tire
size designation.
No letter preceding the size designation
(as illustrated above): Passenger car tire
based on European design standards.
Letter “P” preceding the size designation:
Passenger car tire based on U.S. design
standards.
Letter “LT” preceding the size designation:
Light Truck tire based on U.S. design
standards.
Letter “T” preceding the size designation:
Temporary spare tires which are high
pressure compact spares designed for
temporary emergency use only.Tire width
The tire width1 (
page 355) indicates
the nominal tire width in mm.
Aspect ratio
The aspect ratio2 (page 355) is the
dimensional relationship between tire
section height and section width and is
expressed in percentage. The aspect ratio
is arrived at by dividing section height by
section width.
Tire code
The tire code3 (
page 355) indicates
the tire construction type. The “R” stands
for radial tire type. Letter “D” means diag-
onal or bias ply construction; letter “B”
means belted-bias ply construction.
At the tire manufacturer’s option, any tire
with a speed capability above 149 mph
(240 km/h) can include a “ZR” in the size
designation (for example: 245/40 ZR 18).
For additional information, see “Tire speed
rating” (
page 357).Rim diameter
The rim diameter4 (
page 355) is the
diameter of the bead seat, not the
diameter of the rim edge. Rim diameter is
indicated in inches (in).
Tire load rating
The tire load rating5 (page 355) is a
numerical code associated with the
maximum load a tire can support.
For example, a load rating of 91 corre-
sponds to a maximum load of 1 356 lbs
(615 kg) the tire is designed to support.
See also “Maximum tire load”
(
page 361) where the maximum load as-
sociated with the load index is indicated in
kilograms and lbs.
366 OperationTires and wheelsGVW (G
ross V
ehicle W
eight)
The GVW comprises the weight of the
vehicle including fuel, tools, spare wheel,
installed accessories, passengers and
cargo and, if applicable, trailer tongue
load. The GWV must never exceed the
GWVR indicated on the certification label
located on the driver’s door B-pillar.
GVWR (G
ross V
ehicle W
eight R
ating)
This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the vehicle including all options, passen-
gers, fuel, and cargo and, if applicable,
trailer tongue load). It is indicated on
certification label located on the driver’s
door B-pillar.
Kilopascal (kPa)
The metric unit for air pressure. There are
6.9 kPa to 1 psi; another metric unit for air
pressure is bars. There are 100 kilopascals
(kPa) to 1 bar.Maximum load rating
The maximum load in kilograms and
pounds that can be carried by the tire.
Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
vehicle capacity weight and production
options weight.
Maximum tire inflation pressure
This number is the greatest amount of air
pressure that should ever be put in the tire
under normal driving conditions.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by
68 kilograms (150 lbs).
Occupant distribution
The distribution of occupants in a vehicle
at their designated seating positions.Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.
PSI (P
ounds per s
quare i
nch)
A standard unit of measure for air pressure
-> bar, kilopascal (kPa).
Recommended tire inflation pressure
Recommended tire inflation pressure
listed on placard located on driver’s door
B-pillar for normal driving conditions.
Provides best handling, tread life and
riding comfort.
370 OperationWinter driving
Block heater (Canada only)
The engine is equipped with a block
heater.
The electrical cable may be installed at an
authorized Mercedes-Benz Light Truck
Center.Snow chains
Snow chains should only be driven on
snow-covered roads at speeds not to
exceed 30 mph (50 km/h). Remove chains
as soon as possible when driving on roads
without snow.Please observe the following guidelines
when using snow chains:
Use of snow chains is not permissible
with all wheel/tire combinations.
Snow chains should only be used on
the rear wheels. Follow the manufac-
turer’s mounting instructions.
Only use snow chains that are
approved by Mercedes-Benz. Your
authorized Mercedes-Benz Light Truck
C e n t e r w i l l b e g l a d t o a d v i s e y o u o n t h i s
subject.
Use of snow chains may be prohibited
depending on location. Always check
local and state laws before installing
snow chains.
Warning!
G
If you use your spare tire when winter tires
are fitted on the other wheels, be aware that
the difference in tire characteristics may
very well impair turning stability and that
overall driving stability may be reduced.
Adapt your driving style accordingly.
Have the spare tire replaced with a winter
tire at the nearest authorized
Mercedes-Benz Light Truck Center.
iWhen driving with snow chains, you
may wish to deactivate the ESP
®
(
page 97) before setting the vehicle
in motion. This will improve the
vehicle’s traction.
!Even on vehicles with all-wheel-drive
use snow chains on rear tires only.
The use of snow chains is not permissi-
ble with the spare wheel.
392 Practical hintsWhat to do if …Warning!
G
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
vehicle placard or the tire inflation pressure
label. (If your vehicle has tires of a different
size than the size indicated on the vehicle
placard or the tire inflation pressure label,
you should consult the appropriate section
of this owner’s manual to determine the
proper tire inflation pressure). When the low
tire pressure telltale is illuminated, one or
more of your tires is significantly under-in-
flated. You should stop and check your tires
as soon as possible, and inflate them to the
proper pressure. Driving on a significantly
under-inflated tire causes the tire to over-
heat and can lead to tire failure. Under-infla-
tion also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s han-
dling and stopping ability.
Your vehicle has also been equipped with a
TPMS malfunction telltale to indicate when
the system is not operating properly. When
the malfunction telltale is illuminated, the
system may not be able to detect or signal
low tire pressure as intended. TPMS mal-
functions may occur for a variety of reasons,
including the installation of incompatible
replacement tires on the vehicle. Always
check the TPMS malfunction telltale after
replacing one or more tires on your vehicle
to ensure that the replacement tires are
compatible with the TPMS.