2015 MERCEDES-BENZ S-Class page 459

The tire-change tool kit is kept in a tray in the
stowage well under the trunk floor.
X Open the trunk lid.
X Lift the trunk floor upwards (Y page 377).Flat tire
Preparing the vehicle
Your vehicle may be equipped with: R tires with run-flat characteristics
(MOExtended tires) (Y page 423)
Vehicle preparation is not necessary on
vehicles with MOExtended tires
R a TIREFIT kit (Y page 422)
Information on changing/mounting a wheel
(Y page 465).
X Stop the vehicle on solid, non-slippery and
level ground, as far away as possible from
traffic.
X Switch on the hazard warning lamps.
X Secure the vehicle against rolling away
(Y page 220).
X If possible, bring the front wheels into the
straight-ahead position.
X Switch off the engine.
X Open the driver's door.
The on-board electronics now have status
0. This is the same as the SmartKey having
been removed.
X Remove Start/Stop button from ignition
lock (Y page 189).
or, if the SmartKey is inserted in the ignition
lock:
X Remove the SmartKey from the ignition
lock.
X All occupants must get out of the vehicle.
Make sure that they are not endangered as they do so.
X Make sure that no one is near the danger
area while a wheel is being changed. Any-
one who is not directly assisting in the
wheel change should, for example, stand
behind the barrier. X
Get out of the vehicle. Pay attention to traf-
fic conditions when doing so.
X Close the driver's door. MOExtended tires (tires with run-flat
properties)
General notes With MOExtended tires (tires with run flat
characteristics), you can continue to drive
your vehicle even if there is a total loss of
pressure in one or more tires. The affected
tire must not show any clearly visible damage.
You can recognize MOExtended tires by the
MOExtended marking which appears on the
sidewall of the tire. You will find this marking next to the tire size designation, the load-
bearing capacity and the speed index
(Y page 459).
MOExtended tires may only be used in con-
junction with an active tire pressure loss
warning system or with an active tire pressure
monitor.
If the pressure loss warning message
appears in the multifunction display:
R Observe the instructions in the display
messages (Y page 348).
R Check the tire for damage.
R If driving on, observe the following notes.
The maximum driving distance is approx-
imately 50 miles (80 km) when the vehicle is
partially laden and approximately 18 miles
(30 km) when the vehicle is fully laden.
In addition to the vehicle load, the driving dis- tance possible depends upon:
R Speed
R Road condition
R Outside temperature
The driving distance possible in run-flat mode may be reduced by extreme driving condi-
tions/maneuvers, or it can be increased
through a moderate style of driving. Flat tire
423Roadside Assistance

Some tire pressure tables show only the rim
diameters instead of the full tire size, e.g.
R18 . The rim diameter is part of the tire size
and can be found on the tire sidewall
(Y page 459).
If the tire pressures have been set to the
lower values for lighter loads and/or lower
road speeds, the pressures should be reset to the higher values:
R if you want to drive with an increased load
and/or
R if you want to drive at higher road speeds
i The tire pressures for increased loads
and/or higher road speeds, shown in the
tire pressure table, may have a negative
effect on driving comfort.
If the tire pressure is not set correctly, this
can lead to an excessive build up of heat and
a sudden loss of pressure.
For more information, contact a qualified spe- cialist workshop. Important notes on tire pressure
G
WARNING
If the tire pressure drops repeatedly, the
wheel, valve or tire may be damaged. Tire
pressure that is too low may result in a tire
blow-out. There is a risk of an accident. R Check the tire for foreign objects.
R Check whether the wheel is losing air or the
valve is leaking.
If you are unable to rectify the damage, con-
tact a qualified specialist workshop. G
WARNING
If you fit unsuitable accessories onto tire
valves, the tire valves may be overloaded and malfunction, which can cause tire pressure
loss. Due to their design, retrofitted tire pres- sure monitors keep the tire valve open. This
can also result in tire pressure loss. There is a
risk of an accident. Only screw the standard valve cap or other
valve caps approved by Mercedes-Benz for
your vehicle onto the tire valve.
Use a suitable pressure gauge to check the
tire pressure. The outer appearance of a tire
does not permit any reliable conclusion about
the tire pressure. On vehicles equipped with
the electronic tire pressure monitor, the tire
pressure can be checked in the on-board
computer.
The tire temperature and pressure increase
when the vehicle is in motion. This is depend- ent on the driving speed and the load.
Therefore, you should only correct tire pres-
sures when the tires are cold.
The tires are cold:
R if the vehicle has been parked without
direct sunlight on the tires for at least three
hours and
R if the vehicle has not been driven further
than 1 mile (1.6 km)
The tire temperature changes depending on
the outside temperature, the vehicle speed
and the tire load. If the tire temperature
changes by 18 ‡ (10 †), the tire pressure
changes by approximately 10 kPa (0.1 bar/
1.5 psi). Take this into account when check-
ing 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, the result- ing value will be higher than if the tires were
cold. This is normal. Do not reduce the tire
pressure to the value specified for cold tires.
The tire pressure would otherwise be too low.
Observe the recommended tire pressures for
cold tires:
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
R in the tire pressure table on the inside of the
fuel filler flap Tire pressure
447Wheels and tires Z

on surfaces that are not icy or covered with
snow. Take appropriate care when driving.
Further information on winter tires (M+S
tires) (Y page 444).
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. They represent the tire's resistance to the generation of heat and its ability to dissi-pate heat when tested under controlled con-
ditions on a specified indoor laboratory test
wheel. Sustained 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 :
Uniform Tire Quality Grading Standard
(Ypage 463)
; DOT, Tire Identification Number
(Ypage 462)
= Maximum tire load (Y page 462)
? Maximum tire pressure (Y page 448)
A Manufacturer
B Tire material (Y page 463)
C Tire size designation, load-bearing capa-
city and speed rating (Y page 459)
D Load index (Y page 462)
E Tire name
The markings described above are on the tire in addition to the tire name (sales designa-
tion) and the manufacturer's name.
i Tire data is vehicle-specific and may devi-
ate 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. All about wheels and tires
459Wheels and tires
Z

Load index
In addition to the load-bearing index, load
index
:may also be imprinted on the side-
wall of the tire. You will find this after the let-
ter that identifies the speed rating
(Y page 459).
R If no specification is given: no text (as in the
example above), represents a standard
load (SL) tire
R XL or Extra Load: represents a reinforced
tire
R Light Load: represents a light load tire
R C, D, E: represents a load range that
depends on the maximum load that the tire
can carry at a certain pressure
i Tire data is vehicle-specific and may devi-
ate from the data in the example.
Maximum load rating Maximum tire load
:is the maximum per-
missible weight for which the tire is approved.
Do not overload the tires by exceeding the
specified load limit. The maximum permissi- ble load can be found on the vehicle's Tire and
Loading Information placard on the B-pillar onthe driver's side (Y page 453).
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
DOT, Tire Identification Number (TIN) US 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 retread- ers to inform purchasers of recalls and other
safety-relevant matters. It makes it possible
for the purchaser to easily identify the affec-
ted tires.
The TIN is made up of manufacturer identifi-
cation code ;, tire size=, tire type code ?
and manufacturing date A.
DOT (Department of Transportation): tire
symbol :marks that the tire complies with
the requirements of the U.S. Department of
Transportation.
Manufacturer identification code: manu-
facturer identification code ;provides
details on the tire manufacturer. New tires
have a code with two symbols. Retreaded
tires have a code with four symbols.
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. 462
All about wheels and tiresWheels and tires