331 Operation
Tires and wheels
Tire ply material
1Plies in sidewall
2Plies under tread
This marking tells you about the type of
cord and number of plies in the sidewall
and under the tread.Tire 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
bar.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 kilopascal (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).
i
For illustration purposes only. Actual
data on tires is specific to each vehicle
and may vary from data shown in above
illustration.
333 Operation
Tires and wheels
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 square inch)
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.
TIN (Tire Identification Number)
Unique identifier which facilitates efforts
by tire manufacturers to notify purchasers
in recall situations or other safety matters
concerning tires and gives purchases the
means to easily identify such tires. The TIN
is comprised of “Manufacturer’s identifica-
tion mark”, “Tire size”, “Tire type code”
and “Date of manufacture”.
335 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 a
front-to-rear rotation pattern that will
maintain the intended rotation (spinning)
direction of the tire (
page 308).
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 308).
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 disks, 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 380) and
(
page 404).
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.
364 Practical hints
What to do if …
Display messagePossible cause/consequencePossible solution
Run Flat Indicator
inactive
The Run Flat Indicator* is malfunc-
tioning.Have the Run Flat Indicator* checked by an
authorized Mercedes-Benz Center.
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.
Tire pressure
Check tires
The Run Flat Indicator* indicates
that 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 317).
If necessary, change the wheel (page 404).
Reactivate the Run Flat Indicator* after adjusting
the tire inflation pressure values (
page 319).
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
Insert electrical plug 3 into vehicle
cigarette lighter socket (
page 263).
Turn the SmartKey in the starter switch
to position1.
PressI on electric air pump switch 2.
The electric air pump should now
switch on and inflate the collapsible
tire.
Inflate the tire to approximately 51 psi
(3.5 bar).
This takes about 5 minutes for the col-
lapsible tire. Air hose 4 and union
nut5 can become hot during infla-
tion. Exercise proper caution to avoid
burning yourself when using the equip-
ment.
Press0 on electric air pump switch 2.
Turn the SmartKey in the starter switch
to position0.
If the tire pressure is above 51 psi
(3.5 bar), release excess tire pressure
using the vent screw.
Detach the electric air pump.
Store the electrical plug and the air
hose behind the flap and place the
electric air pump back in the trunk.
!
The cigarette lighter (page 262) is
not designed for use with the electric
air pump. Use the power outlet in the
rear passenger compartment
(
page 263) 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 electric air pump
again after it has cooled off.
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.
429 Technical data
Rims and Tires
Rims and Tires
!
Only use tires which have been tested
and approved for your vehicle by
Mercedes-Benz. Tires approved by
Mercedes-Benz are developed to pro-
vide best possible performance in con-
junction with the driving safety
systems on your vehicle such as ABS or
ESP
®. Tires specially developed for
your vehicle and tested and approved
by Mercedes-Benz can be identified by
finding the following on the tire’s side-
wall:
MO = Mercedes-Benz Original
equipment tires
AMG vehicles:
Does not apply to all approved tires
on AMG vehicles. For information
on tested and approved tires for
AMG vehicles, contact an autho-
rized Mercedes-Benz Center.
Using tires other than those approved
by Mercedes-Benz may result in dam-
age that is not covered by the
Mercedes-Benz Limited Warranty.
!
Using tires other than those approved
by Mercedes-Benz can have detrimen-
tal effects, such as
poor handling characteristics
increased noise
increased fuel consumption
Moreover, tires and rims not approved
by Mercedes-Benz may, under load,
exhibit dimensional variations and dif-
ferent tire deformation characteristics
that could cause them to come into
contact with the vehicle body or axle
parts. Damage to the tires or the vehi-
cle may be the result.
i
Further information on tires and rims is
available at any authorized
Mercedes-Benz Center. A placard with
the recommended tire inflation
pressures is located on the driver’s
door B-pillar. Some vehicles may have
supplemental tire inflation pressure
information for driving at high speeds
(
page 316) or for vehicle loads less
than the maximum loaded vehicle
condition (
page 316). If such infor-
mation is provided, it can be found on
the placard located on the inside of the
fuel filler flap. The tire inflation pres-
sure should be checked regularly and
should only be adjusted on cold tires.
Follow tire manufacturer’s mainte-
nance recommendation included with
vehicle.
433 Technical data
Rims and Tires
Spare wheel (collapsible tire)
ModelC55AMG
Rim (steel)4.5 B x 17 H2
Wheel offset0.47 in (12 mm)
Tire145/70 -17 92P1
1Must not be used with snow chains.
!
Please compare the recommended tire
inflation pressure for your vehicle with
the tire inflation pressure on the yellow
label located on the spare wheel rim.
If the tire inflation pressure on the yel-
low label on the spare wheel rim differs
from the values given in this Operator’s
Manual, inflate the collapsible tire to
the recommended tire inflation pres-
sure given on the yellow label on the
spare wheel rim.
i
Please note that the tire inflation
pressure of the collapsible tire differs
from the tire inflation pressure of the
road tires.
Inflate the collapsible tire to approxi-
mately 51 psi (3.5 bar).
444 Technical terms
CAN system
(C
ontroller Area Network)
Data bus network serving to control
vehicle functions such as door locking
or windshield wiping depending on
vehicle settings and/or ambient
conditions.
Cockpit
All instruments, switches, buttons and
indicator/warning lamps in the
passenger compartment needed for
vehicle operation and monitoring.
Cold tire inflation pressure
(
page 331)
Collapsible tire
An especially compact spare tire that
must be inflated with a provided air
pump before using. It should only be
used to bring the vehicle to the nearest
service station.COMAND*
(C
ockpit Management and Data
System)
Information and operating center for
vehicle sound and communications
systems, including the radio and the
navigation system, as well as other
optional equipment (CD changer*,
telephone*, etc.).
Control system
The control system is used to call up
vehicle information and to change
component settings. Information and
messages appear in the multifunction
display. The driver uses the buttons on
the multifunction steering wheel to
navigate through the system and to
adjust settings.
Cruise control
Driving convenience system that
automatically maintains the vehicle
speed set by the driver.
Curb weight
(
page 332)DOT
(D
epartment of Transportation)
(
page 332)
Engine number
The number set by the manufacturer
and placed on the cylinder block to
uniquely identify each engine
produced.
Engine oil viscosity
Measurement for the inner friction
(viscosity) of the oil at different temper-
atures. The higher the temperature an
oil can tolerate without becoming thin,
or the lower the temperature it can
tolerate without becoming viscous, the
better the viscosity.
ESP
®
(Electronic Stability Program)
Improves vehicle handling and
directional stability.