2008 MERCEDES-BENZ CLS63AMG wheel

310 Operation
Tires and wheels
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 38).
Press thej or kbutton until
the current inflation pressures for each
tire appear in the multifunction display.
iPossible differences between the readings
of a tire pressure gauge of an air hose, e.g. gas
station equipment, and the vehicle’s control sys-
tem can occur. Usually the readings issued by
the control system are more precise.
iWhen the vehicle has been parked for longer
than 20 minutes, the message
Tire pressure
is only displayed after driving for a
few minutes.
appears in the multifunction dis-
play.
Warning!G
It is the driver’s responsibility to calibrate
the TPMS on the recommended cold infla-
tion pressure. Underinflated tires affect the
ability to steer or brake the vehicle. You
might lose control over the vehicle.
iWith a spare wheel without wheel sensor
mounted, the system may still indicate the tire
inflation pressure of the removed wheel for some
minutes. If this happens, keep in mind that the
indicated value where the spare wheel is mount-
ed does not reflect the actual spare tire inflation
pressure.
Warning!G
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust tire inflation pressure according to
the Tire and Loading Information placard on
the driver’s door B-pillar or, if available, the
supplemental tire inflation pressure infor-
mation 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
Tire and Loading Information placard on the
driver’s door B-pillar or, if available, the tire
inflation pressure label on the fuel filler flap.
(If your vehicle has tires of a different size
than the size indicated on the Tire and Load-
ing Information placard or, if available, the
tire inflation pressure label, you should de-
termine the proper tire inflation pressure for
those tires).

311 Operation
Tires and wheels
Tire inflation pressure warnings
If the system detects a significant loss of
tire inflation pressure in one or more than
one tire, a message appears in the multi-
function display.
Example illustration
The respective tire is indicated by a red
rectangle. In addition, a warning signal
sounds.Restarting Advanced TPMS*
The TPMS usually recognizes new refer-
ence values automatically, for example
when you have

adjusted the tire inflation pressure

changed wheels or tires

mounted new wheels or tires
As an added safety feature, your vehicle has
been equipped with a tire pressure monitor-
ing system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires is significantly underinflated. Accord-
ingly, when the low tire pressure telltale illu-
minates, you should stop and check your
tires as soon as possible, and inflate them to
the proper pressure. Driving on a significant-
ly underinflated tire causes the tire to over-
heat and can lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehi-
cle’s handling and stopping 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.iOperating radio transmission equipment
(e.g. wireless headsets, two-way radios) in or
near the vehicle could cause the TPMS to mal-
function.
Warning!G
It is the driver’s responsibility to calibrate
the TPMS on the recommended cold infla-
tion pressure. Underinflated tires affect the
ability to steer or brake the vehicle. You
might lose control over the vehicle.

312 Operation
Tires and wheels
If you want to set new reference values
manually:
Using the Tire and Loading Information
placard on the driver’s door B-pillar or,
if available, the supplemental tire infla-
tion pressure information on the inside
of the fuel filler flap, make sure the tire
inflation pressure of all four tires is cor-
rect.
Press buttonè orÿ on the mul-
tifunction steering wheel repeatedly
until the standard display menu ap-
pears in the multifunction display
(
page 145).
Press thej or kbutton repeat-
edly until you see the current inflation
pressures for each tire appear in the
multifunction display or the following
message appears in the multifunction
display:
Tire pressure
is only displayed
after driving for
a few minutes
Press the reset button (page 27).
The following message will appear in
the multifunction display:
Restart
tire pressure
monitor?
Cancel
Yes
Press the æbutton.
The following message will appear in
the multifunction display:
Tire Pressure
Monitor
Restarted
After driving a few minutes the system
verifies that the current tire inflation
pressures are within the system’s
specified range. Afterwards the current
tire inflation pressures are accepted as
reference pressures and then moni-
tored.
If you wish to cancel activation:
Press the çbutton.
iRestart the TPMS after adjusting the tire in-
flation pressure to the inflation pressure recom-
mended for the vehicle operating condition. Tire
pressure should only be adjusted on cold tires.
Observe the recommended tire inflation pres-
sure on the Tire and Loading Information placard
on the driver’s door B-pillar (
page 296). Some
vehicles may have supplemental tire inflation
pressure information for driving at high speeds
(
page 302) or for vehicle loads less than the
maximum loaded vehicle condition. If such infor-
mation is provided, it can be found on the inside
of the fuel filler flap.

313 Operation
Tires and wheels
Potential problems associated with
underinflated and overinflated tires
Underinflated tires
Underinflated tires can:

cause excessive and uneven tire wear

adversely affect fuel economy

lead to tire failure from being
overheated

adversely affect handling
characteristicsOverinflated tires
Overinflated tires can:

adversely affect handling
characteristics

cause uneven tire wear

be more prone to damage from road
hazards

adversely affect ride comfort

increase stopping distance
MOExtended system*
The MOExtended system allows you to
continue driving your vehicle even if there
is a total loss of pressure in one or more
tires.
You may only use the MOExtended system
in conjunction with the Run Flat Indicator
(Canada only) (
page 304) or the TPMS
(USA only) (
page 306) or the Advanced
TPMS* (Canada only) (
page 309).
For information on driving in case of pres-
sure loss in one or more tires (emergency
mode), see the “Practical hints” section
(
page 419).Warning!G
Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly,
adversely affect handling and fuel economy,
and are more likely to fail from being
overheated.
Warning!G
Follow recommended tire inflation
pressures.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride
comfort, wear unevenly, increase stopping
distance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road
debris, potholes etc.

314 Operation
Tires and wheels
Tire labeling
Besides tire name (sales designation) and
manufacturer name, a number of markings
can be found on a tire.
Following are some explanations for the
markings on your vehicle’s tires:1Uniform Tire Quality Grading Standards
(
page 321)
2DOT, Tire Identification Number (TIN)
(
page 318)
3Maximum tire load (
page 320)
4Maximum tire inflation pressure
(
page 320)
5Manufacturer
6Tire ply material (
page 323)
7Tire size designation, load and speed
rating (
page 314)
8Load identification (
page 318)
9Tire nameTire size designation, load and speed
rating
1Tire width
2Aspect ratio in %
3Radial tire code
4Rim diameter
5Tire load rating
6Tire speed rating
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
For more information, see “Rims and tires”
(
page 438).
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.

315 Operation
Tires and wheels
General:
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 314) indicates
the nominal tire width in mm.
Aspect ratio
The aspect ratio2 (
page 314) 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 314) 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 316).
Rim diameter
The rim diameter4 (
page 314) is the
diameter of the bead seat, not the
diameter of the rim edge. Rim diameter is
indicated in inches (in).

316 Operation
Tires and wheels
Tire load rating
The tire load rating5 (
page 314) 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 320) where the maximum load as-
sociated with the load index is indicated in
kilograms and lbs.
For additional information on tire load
rating, see “Load identification”
(
page 318).Tire speed rating
The tire speed rating6 (
page 314)
indicates the approved maximum speed
for the tire.
Warning!G
The tire load rating must always be at least
half of the GAWR (
page 324) of your
vehicle. Otherwise, tire failure may be the
result which may cause an accident and/or
serious personal injury to you or others.
Always replace rims and tires with the same
designation, manufacturer and type as
shown on the original part.
Warning!G
Do not overload the tires by exceeding the
specified total load limit as indicated on the
Tire and Loading Information placard locat-
ed on the driver’s door B-pillar. Overloading
the tires can overheat them, possibly caus-
ing a blowout. Overloading the tires can also
result in handling or steering problems, or
brake failure.
iTire load rating5 (page 314) and tire
speed rating6 (
page 314) are also referred
to as “service description”.
Warning!G
Even when permitted by law, never operate
a vehicle at speeds greater than the
maximum speed rating of the tires.
Exceeding the maximum speed for which
tires are rated can lead to sudden tire
failure, causing loss of vehicle control and
possibly resulting in an accident and/or
personal injury and possible death, for you
and for others.
iTire load rating5 (page 314) and tire
speed rating6 (
page 314) are also referred
to as “service description”.

317 Operation
Tires and wheels
Summer tires

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 exam-
ple: 245/40 ZR18). To determine the
maximum speed capability of the tire,
the service description for the tire must
be referred to. The service description is comprised of the tire load rating5
(
page 314) and the tire speed
rating6 (
page 314).
If your tire includes “ZR” in the size
designation and no service
description5 and6 (
page 314) is
given, the tire manufacturer must be
consulted for the maximum speed
capability.
If a service description5 and6
(
page 314) is given, the speed capa-
bility is limited by the speed symbol in
the service description.
Example: 245/40 ZR18 97Y.
In this example, “97Y” is the service
description. The letter “Y” designates
the speed rating and the speed capabil-
ity of the tire is limited to 186 mph
(300 km/h).

Any tire with a speed capability above
186 mph (300 km/h) must include a
“ZR” in the size designation AND the
service description must be placed in
parenthesis. Example: 275/40 ZR 18
(99Y). The “(Y)” speed rating in paren-
thesis designates the maximum speed
capability of the tire as being above
186 mph (300 km/h). Consult the tire
manufacturer for the actual maximum
permissible speed of the tire.
All-season and winter tires
IndexSpeed rating
Qup to 100 mph (160 km/h)
Rup to 106 mph (170 km/h)
Sup to 112 mph (180 km/h)
Tup to 118 mph (190 km/h)
Hup to 130 mph (210 km/h)
Vup to 149 mph (240 km/h)
Wup to 168 mph (270 km/h)
Yup to 186 mph (300 km/h)
(Y)above 186 mph (300 km/h)
ZRabove 149 mph (240 km/h)
IndexSpeed rating
QM+S1
1or M+S.for winter tires
up to 100 mph (160 km/h)
TM+S1up to 118 mph (190 km/h)
HM+S1up to 130 mph (210 km/h)
VM+S1up to 149 mph (240 km/h)