344 OperationTires and wheelsTire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, radio, and heater, to the extent that
these items are available as
factory-installed equipment (whether
installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire.
Air pressure is expressed in pounds per
square inch (psi), or kilopascal (kPa), or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.Bar
Another metric unit for air pressure. There
are 14.5038 pounds per square inch (psi)
to 1 bar; there are 100 kilopascals (kPa)
to 1 bar.
Bead
The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the
rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle
has been sitting for at least three hours or
driven no more than one mile (1.6 km).
Curb weight
The weight of a motor vehicle with stan-
dard equipment including the maximum
capacity of fuel, oil, and coolant, and, if so
equipped, air conditioning and additional
optional equipment, but without passen-
gers and cargo.DOT (D
epartment o
f T
ransportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross A
xle W
eight R
ating)
The GAWR is the maximum permissible
axle weight. The gross vehicle weight on
each axle must never exceed the GAWR for
the front and rear axle indicated on the
certification label located on the driver’s
door B-pillar.
GVW (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.
345 Operation
Tires and wheels
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.
Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
Sidewall
The portion of a tire between the tread and
the bead.
347 Operation
Tires and wheels
Rotating tires
Tire rotation can be performed on vehicles
with tires of the same dimension all
around. If your vehicle is equipped with
tires of the same dimension all around,
tires can be rotated, observing a
front-to-rear rotation pattern that will
maintain the intended rotation (spinning)
direction of the tire (
page 320).
In some cases, such as when your vehicle
is equipped with mixed-size tires (different
tire dimension front vs. rear), tire rotation
is not possible.If applicable to your vehicle’s tire configu-
ration, tires can be rotated according to
the tire manufacturer’s recommended in-
tervals in the tire manufacturer’s warranty
pamphlet located in your vehicle literature
portfolio. If none is available, tires should
be rotated every 3 000 to 6 000 miles
(5 000 to 10 000 km), or sooner if neces-
sary, according to the degree of tire wear.
The same rotation (spinning) direction
must be maintained (
page 320).
Rotate tires before the characteristic tire
wear pattern becomes visible (shoulder
wear on front tires and tread center wear
on rear tires).
Thoroughly clean the mounting face of
wheels and brake discs, i.e. the inner side
of the wheels/tires, during each rotation.
Check for and ensure proper tire inflation
pressure.For information on wheel change, see the
“Practical hints” section (
page 388) and
(
page 408).
Warning!
G
Rotate front and rear wheels only if the tires
are of the same dimension.
If your vehicle is equipped with mixed-size
tires (different tire dimensions front vs.
rear), tire rotation is not possible.
Warning!
G
Have the tightening torque checked after
changing a wheel. Wheels could become
loose if not tightened with a torque of
80 lb-ft (110 Nm).
Only use genuine Mercedes-Benz wheel
bolts specified for your vehicle’s rims.
373 Practical hints
What to do if …
Display messages
Possible cause/consequence
Possible solution
Run Flat Indicator
inactive
The Run Flat Indicator* is malfunc-
tioning.
Have the Run Flat Indicator* checked by an
authorized Mercedes-Benz Center.
Tire pressure
Check tires
The pressure is too low in one or
more tires.
Carefully bring the vehicle to a halt, avoiding
abrupt steering and braking maneuvers. Observe
the traffic situation around you.
Check and adjust the tire inflation pressure as
required (
page 329).
If necessary, change the wheel (
page 408).
Reactivate the Run Flat Indicator* after adjusting
the tire inflation pressure values (
page 304).
Check tires
Then reactivate
Run Flat Indicator
There was a warning message about
a loss in tire inflation pressure and
the Run Flat Indicator* has not been
reactivated yet.
Make sure that the correct tire inflation pressure
is set for each tire.
Then reactivate the Run Flat Indicator*.
Run Flat Indicator
unavailable
The Run Flat Indicator* has been
switched off due to an error.
Have the Run Flat Indicator* checked by an
authorized Mercedes-Benz Center.
Warning!
G
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle.
You may lose control of the vehicle. Contin-
ued driving with a flat tire will cause exces-
sive heat build-up and possibly a fire.
409 Practical hints
Flat tire
Foreign objects (e.g. screws or nails)
should not be removed from the tire.
Take TIREFIT, the sticker, and the elec-
tric air pump out of the trunk.
Attach the sticker where it will be easily
seen by the driver on the instrument
cluster.1TIREFIT container
2Flap
3Notch
4Electrical plug
5Air hose
6Flange
Open flap2 on the electric air pump.
Pull plug4 and air hose5 out of the
pump housing.
Warning!
G
TIREFIT is a limited repair device. TIREFIT
cannot be used for cuts or punctures larger
than approx. 0.16 in (4 mm) and tire dam-
age caused by driving with extremely low
tire inflation pressure, or on a flat tire, or a
damaged wheel.
Do not drive the vehicle under such circum-
stances.
Contact your nearest Mercedes-Benz
Center for assistance or call Roadside
Assistance.
Warning!
G
Take care not to allow the contents of
T I R E F I T t o c o m e i n c o n t a c t w i t h h a i r , e y e s o r
clothing. TIREFIT is harmful if inhaled, swal-
lowed or absorbed through the skin - causes
skin, eye and respiratory irritation.
Any contact with eyes or skin should be
flushed immediately with plenty of water.
If clothing comes in contact with TIREFIT,
change clothing as soon as possible.
In case of allergic reaction or rash, consult a
physician immediately.Warning!
G
Keep TIREFIT out of reach of children.
If swallowed, rinse mouth immediately with
plenty of water and drink plenty of water.
Do not induce vomiting!
Consult a physician immediately.
Keep away from open flame or heat source.
iIf sealant has leaked out, let it dry. You
can then peel it off.
410 Practical hintsFlat tire
Screw the air pump’s air hose5 onto
flange6 of the TIREFIT container.
Stick TIREFIT container1 upside
down into notch3 of the electric air
pump.
7Tire valve
8Electric air pump switch
9Pressure gauge and vent screw
aFiller hose
Unscrew the valve cap from tire
valve7.
Screw filler hosea onto tire valve7.
Close vent screw9 on air hose4.
Insert electrical plug4 into the power
outlet in the passenger footwell
(page 271).
Turn the SmartKey in the starter switch
to position1 (
page 36).
Press I on electric air pump switch8.
The electric air pump should now
switch on and inflate the tire.After 5 minutes, the pressure gauge must
display at least 26 psi (1.8 bar). The air
hose can become hot during inflation.
Please exercise appropriate caution.
If this tire inflation pressure is not at-
tained, turn off the electric air pump,
detach the filler hose from the tire
valve, and drive vehicle back and forth
very slowly approximately 30 ft (10 m).
This serves to better distribute the
TIREFIT sealant material inside the tire.
Unscrew the air pump’s air hose5
from flange6 of the TIREFIT contain-
er.
Screw air hose5onto tire valve7.
Inflate the tire again.
Warning!
G
Observe safety instructions on air pump la-
bel.
!The cigarette lighter (
page 270) is
not designed for use with the electric
air pump. Use the power outlet in the
passenger footwell (
page 271) for
electric air pump operation.
!Do not operate the electric air pump
longer than 6 minutes without interrup-
tion. Otherwise it may overheat.
You may operate the air pump again af-
ter it has cooled off.
411 Practical hints
Flat tire
After attaining a tire inflation pressure
of 26 psi (1.8 bar), press 0 on electric
air pump switch8.
The electric air pump should now be
switched off.
Turn the SmartKey in the ignition to
position0 (
page 36).
Detach the electric air pump.
The air hose may still be hot. Please ex-
ercise appropriate caution.
Store the electrical plug and the air
hose behind the flap and place the
electrical air pump back in the trunk.
Close the trunk lid.
Drive off immediately.
The TIREFIT sealant will distribute itself
evenly inside the tire.
After driving the vehicle for an initial
10 minutes, check the tire inflation
pressure using pressure gauge 9 on
the air pump.
Warning!
G
If a tire inflation pressure of 26 psi (1.8 bar)
is not attained, tire is too severely damaged
for TIREFIT to provide a reliable tire repair.
In this case, TIREFIT cannot properly seal
the tire.
Do not drive the vehicle.
Contact the nearest Mercedes-Benz Center
or call Roadside Assistance.
Warning!
G
Do not exceed vehicle speed of
50 mph (80 km / h). A TIREFIT repair is not
designed to operate at higher speeds.
The sticker must be attached on the instru-
ment cluster where it will be easily seen by
the driver.
Vehicle handling characteristics may
change. Adapt your driving accordingly.
Warning!
G
If tire inflation pressure has fallen below
20 psi (1.3 bar) do not continue to drive the
vehicle.
Park your vehicle safely away from the road-
way and contact the nearest authorized
Mercedes-Benz Center or Roadside
Assistance.
If tire inflation pressure is at least
20 psi (1.3 bar), inflate tire to correct pres-
sure (see placard on the driver’s door
B-pillar), and drive vehicle to nearest tire re-
pair facility to have tire repaired or replaced.
Recommended duration of use:
300 miles (500 km) at 50 mph (80 km/h)
with the recommended tire inflation pres-
sure.
412 Practical hintsFlat tire
Visit an authorized Mercedes-Benz
Center as soon as possible to obtain a
new TIREFIT kit.
Bring used TIREFIT materials to an
authorized Mercedes-Benz Center for
proper disposal.
Replace your TIREFIT container every
4 years. Replacement containers are
available at your authorized
Mercedes-Benz Center.
Mounting the spare wheel
Warning!
G
Follow recommend inflation pressures.
Do not overinflate tires. Overinflating tires
can result in sudden deflation (blowout) be-
cause they are more likely to become punc-
tured or damaged by road debris, potholes,
etc.
Do not underinflate tires. Underinflated tires
wear unevenly, adversely affect handling
and fuel economy, and are more likely to fail
from being overheated.
Do not overload the tires by exceeding the
specified vehicle capacity weight (as indicat-
ed by the label on the pillar in the driver’s
door opening). Overloading the tires can
overheat them, possibly causing a blowout.
Warning!
G
Do not exceed vehicle speed of 50 mph
(80 km/h). A TIREFIT repair is not designed
to operate at higher speeds.
The sticker must be attached on the instru-
ment cluster where it will be easily seen by
the driver.
Vehicle handling characteristics may
change. Adapt your driving accordingly.
Warning!
G
The dimensions of the spare wheel with col-
lapsible tire are different from those of the
road wheels. As a result, the vehicle han-
dling characteristics change when driving
with a spare wheel with collapsible tire
mounted. Adapt your driving style accord-
ingly.
The spare wheel with collapsible tire is for
temporary use only. When driving with spare
wheel with collapsible tire mounted, ensure
proper tire inflation pressure and do not ex-
ceed vehicle speed of 50 mph (80 km/h).