MERCEDES-BENZ CLS COUPE 2008 Owners Manual
Page 201 of 329
Tyres and wheels
198 Tyres and wheels
Points to remember
! For safety reasons, Mercedes-Benz rec-
ommends that you only use tyres and
wheels which have been approved by
Mercedes-Benz specifically for your vehi-
cle. These tyres have been specially adap-
ted for use with the control systems, such
as
ABS or ESP ®
, and are marked as follows:
R MO = Mercedes-Benz Original
R MOE = Mercedes-Benz Original Extended
(with run-flat characteristics)*
Mercedes-Benz Original Extended tyres*
should only be used on wheels that have
been specifically approved by Mercedes-
Benz.
If you use other tyres and wheels,
Mercedes-Benz cannot accept any respon-
sibility for damage that may result from
this. Further information about tyres,
wheels and approved combinations can be
obtained from any Mercedes-Benz Service
Centre.
If you use tyres other than those tested and
recommended for Mercedes-Benz vehi-
cles, characteristics such as handling, vehi-
cle noise emissions and fuel consumption may be adversely affected. In addition, the
wheels may come into contact with the
body
or axle components when heavily loa-
ded or when driving with snow chains. This
could result in damage to the tyres or the
vehicle.
! Retreaded tyres are neither tested nor
recommended by Mercedes-Benz, since
previous damage cannot always be detec-
ted on retreaded tyres. As a result,
Mercedes-Benz cannot guarantee vehicle
safety if retreaded tyres are fitted. Do not
fit used tyres if you have no information
about their previous usage. G
Risk of accident
If wheels or tyres other than those which
have been tested are fitted:
R the
brakes or chassis components could
be damaged
R wheel and tyre clearances can no longer
be guaranteed
This could cause an accident.
Modification work on the brake system and
wheels is not permitted, nor is the use of
spacer plates or brake dust shields. This inva-
lidates the General Operating Permit for the
vehicle. Notes on selecting, fitting and replacing
tyres R
Only fit tyres and wheels of the same type
and make.
R Only fit tyres of the correct size onto the
wheels.
R After
fitting new tyres, run them in at mod-
erate speeds for the first 100 km as they
only reach their full performance after this
distance.
R Fit new tyres on the front wheels first if
tyres of the same size are required on the
front and rear wheels.
R Replace the tyres after six years at the lat-
est, regardless of wear. This also applies to
the spare wheel*.
R Do not drive with tyres which have too little
tread depth as this significantly reduces
the traction on wet roads (aquaplaning).
! Store tyres that are not being used in a
cool, dry and preferably dark place. Protect
the tyres against oil, grease, petrol and die-
sel. Operation
* optional
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Tyres and wheels
199
Notes on regularly inspecting wheels
and tyres R
Regularly check the wheels and tyres of
your
vehicle for damage (e.g. cuts, punctu-
res, tears, bumps on tyres and deforma-
tion, cracks or severe corrosion on wheels),
at least every 14 days, as well as after off-
road trips or after travelling on rough roads.
Damaged wheels could cause a loss of tyre
pressure.
R Regularly check the tyre tread depth and
the condition of the tread across the whole
width of the tyre (Y page 200). If neces-
sary, turn the front wheels to full lock in
order to inspect the inner side of the tyre
surface.
R All wheels must have a valve cap to protect
the valve against dirt and moisture.
R Regularly check the pressure of all your
tyres (including the spare tyre*), particu-
larly prior to long trips, and correct the
pressure as necessary ( Y page 200).
Notes on driving R
While driving, pay attention to vibrations,
noises and unusual handling characteris- tics, e.g. pulling to one side. This may indi-
cate
that the wheels or tyres are damaged.
If you suspect that a tyre is defective,
reduce your speed and stop the vehicle as
soon as possible to check the wheels and
tyres for damage. Hidden tyre damage
could also be causing the unusual handling
characteristics. If you find no signs of dam-
age, have the wheels and tyres inspected
at a specialist workshop, for example at a
Mercedes-Benz Service Centre.
R When parking your vehicle, make sure that
the tyres do not get deformed by the kerb
or other obstacles. If it is necessary to drive
over kerbs, speed humps or similar, try to
do so slowly and at an obtuse angle. Oth-
erwise, the tyres, particularly the sidewalls,
could get damaged. Direction of rotation
Direction of rotation Tyres with a specified direction of rotation
have
additional benefits, e.g. if there is a risk
of aquaplaning. You will only gain these ben-
efits if the correct direction of rotation is
observed.
An arrow on the sidewall of the tyre indicates
its correct direction of rotation.
i You may fit a spare tyre* against the
direction of rotation. MOExtended run-flat system*
The MOExtended run-flat system allows you
to
continue driving the vehicle even when one
or more tyres lose all air pressure.
The MOExtended run-flat system may only be
used in conjunction with the tyre pressure
loss warning system or the tyre pressure
monitor* and on wheels specifically tested by
Mercedes-Benz.
i Vehicles with MOExtended run-flat sys-
tem are not equipped with the TIREFIT
kit* 25
.
25 Only for certain countries Operation
* optional
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Tyres and wheels
200It is therefore recommended to additionally
equip your vehicle with the TIREFIT kit*
when fitting tyres that do not feature run-
flat properties, e.g. winter tyres.
i A TIREFIT kit*
is available from any quali-
fied specialist workshop, e.g. a Mercedes-
Benz Service Centre.
You will find notes on driving with a flat tyre
in the "Practical advice" section
(Y page 287). Tyre tread
G
Risk of accident
Bear in mind that:
R tyre grip decreases rapidly on wet roads
when
the tread depth is less than 3 mm.
You should thus replace tyres that have
insufficient tread.
R winter tyres should be replaced when the
tread depth is 4 mm or less because oth-
erwise they no longer provide adequate
grip.
R the tread on a tyre may not wear evenly.
You should thus regularly check the tread
depth and the condition of the tread across the entire width of all tyres. If nec-
essary, turn the steering wheel so that
you can see the tyre tread more easily.
You could otherwise lose control of the
vehicle and cause an accident due to the
reduced grip of the tyres on the road. Tyre pressures
G
Risk of accident
Tyre pressure that is either too high or too
low has a negative effect on the vehicle’s
active
safety, which could lead you to cause
an accident. You should therefore regularly
check the pressure of all your tyres (includ-
ing the spare tyre*), particularly prior to
long trips, and correct the pressure as nec-
essary.
To test tyre pressure, use a suitable pressure
gauge. The outer appearance of a tyre does
not permit any reliable conclusion about the
tyre pressure. On vehicles fitted with the elec-
tronic tyre pressure monitor*, the tyre pres-
sure can be checked in the on-board com-
puter.
If the vehicle is to be heavily laden or driven
at high speeds, the tyre pressure must be adapted according to the specifications given
in the fuel filler flap
(Y page 190).
Use the highest specified tyre pressure for
the spare wheel*. G
Risk of accident
Should the tyre pressure drop repeatedly:
R Check the tyre for foreign bodies.
R Check whether the wheel is losing air or
the valve is leaking.
Tyre
pressure that is too low has a negative
effect on the vehicle’s active safety, which
could lead to your causing an accident.
Tyre pressure changes by approximately
0.1 bar for every 10 °C change in ambient
temperature.
If you measure the tyre pressure in enclosed
spaces where the temperature differs from
the outside temperature, you will have to cor-
rect the measured value accordingly.
When the vehicle is driven, the tyre tempera-
ture, and with it the tyre pressure, will
increase depending on the road speed and
the load on the tyres.
Therefore, you should only correct tyre pres-
sures when the tyres are cold. Operation
* optional
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Tyres and wheels
201
The pressure of warm tyres should only be
corrected
if it is too low for the current oper-
ating conditions.
You will find a table of tyre pressures for var-
ious operating conditions on the inside of
your vehicle's fuel filler flap.
Driving with tyre pressure that is too high or
too low can:
R shorten the service life of the tyres
R cause increased tyre damage
R have a negative effect on handling charac-
teristics (e.g. by causing aquaplaning)
i The tyre pressure values given for low
loads are minimum values which offer you
good ride comfort characteristics.
You can, however, also use the values given
for higher loads. These are permissible and
will not adversely affect the running of the
vehicle.
Also check the tyre pressure of the spare
wheel*. H
Environmental note
Check the tyre pressure regularly, and at
least every 14 days. Tyre pressure loss warning system
G
Risk of accident
The tyre pressure loss warning system does
not
warn you of an incorrectly set tyre pres-
sure. The table on the inside of the fuel filler
flap will help you decide whether the tyre
pressures should be corrected.
The tyre pressure loss warning system does
not replace the need to regularly check
your vehicle's tyre pressures, since an even
loss of pressure on several tyres at the
same time cannot be detected by the tyre
pressure loss warning system.
The tyre pressure loss warning system is
not able to warn you of a sudden loss of
pressure, e.g. if the tyre is penetrated by a
foreign object.
In the event of a sudden loss of pressure,
bring the vehicle to a halt by braking care-
fully. Do not make any sudden steering
movements when doing so.
While the vehicle is in motion, the tyre pres-
sure loss warning system monitors the set
tyre pressure using the rotational speed of
the wheels. This enables the system to detect
significant pressure loss in a tyre. If the speed
of rotation of a wheel changes as a result of
a loss of pressure, a corresponding warning message will appear in the multi-function dis-
play.
The
function of the tyre pressure loss warning
system is limited or delayed if:
R snow chains are fitted to your vehicle's
tyres
R road conditions are wintry
R you are driving on sand or gravel
R you adopt a very sporty driving style (cor-
nering at high speeds or driving with high
rates of acceleration)
R you are driving with a heavy load (in the
vehicle or on the roof)
Restarting the tyre pressure loss warn-
ing system Restart the tyre pressure loss warning system
if you have:
R
changed the tyre pressure
R changed the wheels or tyres
R fitted new wheels or tyres
X Before restarting, consult the table of tyre
pressures
on the inside of the fuel filler flap
to ensure that the tyre pressure in all four Operation
* optional
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Tyres and wheels
202tyres is set correctly for the operating con-
ditions concerned.
X Also observe the notes in the section on
tyre pressures ( Y page 200). G
Risk of accident
The tyre pressure loss warning system can
only give reliable warnings if you have set
the correct tyre pressure.
If an incorrect tyre pressure is set, these
incorrect values will be monitored.
A tyre with insufficient pressure results in
an instability of the vehicle when driving,
thus increasing the risk of an accident.
X Make sure that the key is in position 2 in
the ignition lock.
The standard display appears in the multi-
function display ( Y page 115).
X Press k or j to select the tyre pres-
sure function:
Run Flat Indicator active
Menu: R-Button æ
X Press the reset button on the left of the
instrument cluster.
The following message appears in the
multi-function display:
Restart Run Flat Indicator? Yes Cancel
If you wish to confirm the restart:
X Press the æ button.
The following message appears in the
multi-function display:
Run Flat Indicator restarted
After a teach-in period, the tyre pressure
loss warning system will monitor the set
tyre pressures of all four tyres.
If you wish to cancel the restart:
X Press the ç button.
or
X Wait until the message
Restart Run Flat Indicator?
Yes Cancel disappears.
The tyre pressure values stored at the last
restart will continue to be monitored. Checking the tyre pressure electroni-
cally*
The tyre pressure monitor only functions if
the correct wheel electronics are fitted to all
wheels.
These monitor the pressure in all four
tyres, which you have set when restarting the
tyre pressure monitor. The monitor warns you
when the pressure drops in one or more of
the tyres. G
Risk of accident
The tyre pressure monitor does not warn
you
of an incorrectly set tyre pressure. The
table on the inside of the fuel filler flap will
help you decide whether the tyre pressures
should be corrected.
The tyre pressure monitor is not able to
warn you of a sudden loss of pressure, e.g.
if the tyre is penetrated by a foreign object.
In the event of a sudden loss of pressure,
bring the vehicle to a halt by braking care-
fully. Do not make any sudden steering
movements when doing so.
i The operation of the tyre pressure moni-
tor can be affected by interference from
radio transmitting equipment (e.g. radio
headphones, two-way radios) that may be
being operated in or near the vehicle. Operation
* optional
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Tyres and wheels
203
i
If you are carrying a deflated tyre in the
vehicle, you may only reactivate the tyre
pressure monitor if:
R the deflated tyre is no longer in the vehi-
cle
R you have adjusted the tyre pressure cor-
rectly
Calling up the tyre pressure using the
on-board computer X
Make sure that the key is in position 2 in
the ignition lock.
X Press the j or k button to select the
tyre pressure function. The current tyre pressure for each wheel will
be displayed.
If the vehicle has been parked for longer than
20 minutes or you have not driven faster than
25 km/h since the vehicle was parked, the
following message appears: Tyre pressure displayed only after
driving for a few minutes
i
The tyre pressure values indicated by the
on-board computer may differ from those
measured at a filling station with a pressure
gauge. The tyres pressures shown by the
on-board computer refer to those meas-
ured at sea level. The tyre pressure values
indicated by the on-board computer may
differ when the vehicle is at high altitude.
In this case, do not reduce the tyre pres-
sures.
Tyre pressure warning If the tyre pressure on one or more wheels
drops significantly, a message appears in the
multi-function display.
The tyre pressure of the affected wheel(s) will
be displayed in a red rectangle. You will also
hear a warning tone.
Restarting the tyre pressure monitor
In most cases, the tyre pressure monitor will
automatically detect the new reference val-
ues, e.g. if you have:R
changed the tyre pressure
R changed the wheels or tyres
R fitted new wheels or tyres
If you wish to define the new reference values
manually:
X Use the table on the inside of the fuel filler
flap to ensure that the tyre pressure is set
correctly in all four tyres for the current
operating conditions.
Also observe the notes in the section on
tyre pressures ( Y page 200).
X Make sure that the key is in position 2 in
the ignition lock.
The standard display appears in the multi-
function display ( Y page 115).
X Press the j or k button to select the
Tyre pressure function or wait until the
following message appears:
Tyre pressure displayed only after
driving for a few minutes Operation
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Winter driving
204
X
Press the reset button on the left of the
instrument cluster
(Y page 209).
The following message appears in the
multi-function display: Check current
tyre pressure?
X Press the æ button.
The following message appears in the
multi-function display:
Tyre pressure monitor restarted
The tyre pressure monitor has stored the
pressure of the tyres as a new reference
value.
If you wish to cancel the restart:
X Press the ç button. Winter driving
Have your vehicle winterproofed at a qualified
specialist workshop, e.g. at a Mercedes-Benz
Service Centre, at the onset of winter.
! Do not use a sharp object to remove snow
or ice from the trim on the B-pillar between
the side windows. Winter tyres
Use
winter tyres at temperatures below +7 °
C and on snow or ice-covered roads. Only
then can the effect of the ABS and ESP ®
driv-
ing systems be ensured in winter too.
Use winter tyres of the same make and tread
on all wheels to maintain safe handling char-
acteristics. G
Risk of accident
You must replace winter tyres with a tread
depth
of less than 4 mm immediately. They
are no longer suitable for winter use, in par-
ticular because they do not provide suffi-
cient grip. This could cause you to lose
control of your vehicle and cause an acci-
dent. Always observe the maximum permitted
speed
specified for the winter tyres you have
fitted. If you fit winter tyres which have a
lower maximum permitted speed than that of
the vehicle, affix an appropriate warning sign
in the driver's field of vision. This can be
obtained at a qualified specialist workshop,
e.g. from a Mercedes-Benz Service Centre.
In such circumstances, you should also
restrict the maximum speed of the vehicle
using permanent Speedtronic 26
to the maxi-
mum permissible speed for winter tyres
(Y page 144).
Once you have fitted the winter tyres:
X Restart the tyre pressure moni-
tor* (Y page 202). G
Risk of accident
If you fit the spare wheel* when driving with
winter tyres, bear in mind that driving sta-
bility will be impaired owing to unstable
cornering
characteristics caused by the dif-
ferent tyres. You should therefore adapt
your driving style and drive carefully.
Have the spare wheel* replaced at the
nearest qualified specialist workshop
which has the necessary specialist knowl-
edge and tools to carry out the work
26 Only available for certain countries. Operation
* optional
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Winter driving
205required. Mercedes-Benz recommends
that you use a Mercedes-Benz Service
Centre
for this purpose. In particular, work
relevant to safety or on safety-related sys-
tems must be carried out at a qualified
specialist workshop. Snow chains
For safety reasons, Mercedes-Benz recom-
mends that you only use snow chains which
have
been specially approved for your vehicle
by Mercedes-Benz or are of a corresponding
standard of quality.
! Information about the use of snow chain-
compatible AMG winter tyres is applicable
for AMG tyres. Use of snow chains is only
permissible with these tyres.
If you intend to fit snow chains, please bear
the following points in mind: R
Snow
chains cannot be fitted to all wheel/
tyre combinations.
R Snow chains must not be fitted to emer-
gency spare wheels, e.g. the "Minispare" or
collapsible emergency spare wheel.
R Fit snow chains to both rear wheels. Com-
ply with the manufacturer's installation
instructions.
! If snow chains are fitted to the front
wheels, they may come into contact with
the bodywork and axle components when
the vehicle is in motion and damage the
tyre or the vehicle.
On vehicles with AIRMATIC DC*, you must
only drive at raised vehicle level if snow
chains have been fitted (Y page 146).
Do not exceed the maximum permissible
speed of 50 km/h.
i You may wish to deactivate ESP ®
when
pulling away with snow chains fitted
(Y page 59). This way you can allow the
wheels to spin in a controlled manner, ach-
ieving an increased driving force (cutting
action). Winter driving
G
Risk of accident
Do not shift down for additional engine
braking on a slippery road surface. This
could cause the drive wheels to lose their
grip and the vehicle could skid.
You
should drive particularly carefully on slip-
pery road surfaces. Avoid sudden accelera-
tion, steering and braking manoeuvres.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:
X Shift the selector lever to N.
X Try to bring the vehicle under control using
corrective steering. Operation
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Driving tips
206 Driving tips
Rolling with the engine switched off
G
Risk of accident
Never switch the engine off while the vehi-
cle is in motion.
There
is no power assistance for the steer-
ing and the service brake when the engine
is not running.
You will require considerably more effort to
steer and brake and you could therefore
lose control of the vehicle and cause an
accident. Braking
G
Risk of accident
Do not change down for additional engine
braking on a slippery road surface. This
could cause the drive wheels to lose their
grip and the vehicle could skid. G
Risk of accident
Make sure that other road users are not
endangered by your braking. Downhill gradients On long and steep downhill gradients, espe-
cially if the vehicle is laden, you must select
shift range 1, 2 or 3 in good time.
i
This also applies if you have activated
cruise control, Speedtronic or Distronic*
.
This uses the braking effect of the engine and
you will not have to brake to such an extent
to maintain the same speed. This relieves the
load on the brake system and prevents the
brakes from overheating and wearing too
quickly. If you need additional braking,
depress the brake pedal repeatedly rather
than continuously.
Heavy and light loads If the brakes have been subjected to a heavy
load,
do not stop the vehicle immediately, but
drive on for a short while. This allows the air-
flow to cool the brakes more quickly. G
Risk of accident
Never depress the brake pedal continu-
ously while the vehicle is in motion, e.g.
never cause the brakes to rub by applying
constant
slight pedal pressure. This causes
the brake system to overheat, increases the braking distance and can lead to the
brakes failing completely.
If
the brakes have been used only moderately,
you should occasionally test their effective-
ness. To do this, brake more firmly from a
higher speed. This improves the grip of the
brakes.
Wet roads If driving in heavy rain for a prolonged period
of time without braking, there may be a
delayed
reaction from the brakes, when brak-
ing for the first time. You must brake harder.
You must therefore maintain a greater dis-
tance from the vehicle in front.
Brake firmly after driving on a wet road. This
way the brake discs will become warm, drying
more quickly, which will protect them against
corrosion.
Limited braking performance on salted
roads G
Risk of accident
The layer of salt on the brake discs and the
brake pads/linings may cause a delay in
the braking effect, resulting in a signifi- Operation
* optional
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Driving tips
207cantly longer braking distance, which could
lead to an accident.
To avoid this danger, you should:
R
occasionally
brake carefully, without put-
ting other road users at risk, when you
are driving on salted roads. This helps to
remove any salt that may have started to
build up on the brake discs and the brake
pads/linings.
R maintain a greater distance to the vehicle
ahead and drive with particular care.
R carefully apply the brakes at the end of a
trip and immediately after commencing a
new trip, so that salt residues are
removed from the brake disc.
New brake linings For safety reasons, Mercedes-Benz recom-
mends that you only have only brake pads/
linings fitted to your vehicle that have been
approved for Mercedes-Benz vehicles or
which correspond to an equivalent quality
standard.
Brake pads/linings which have not
been approved for Mercedes-Benz or which
are not of an equivalent quality could affect
your vehicle's operating safety. G
Risk of accident
New brake pads/linings only reach their
optimum braking effect after several hun-
dred
kilometres of driving. Before this opti-
mum braking effect is reached, you should
compensate for the reduced braking effect
by applying greater pressure when braking.
This also applies after the brake discs or the
brake pads/linings have been replaced.
High-performance brake system for
AMG vehicles The high-performance brake system is
designed for heavy loads. Braking can there-
fore cause noises. This will depend on:
R
Speed
R Braking force
R Environmental
conditions, such as temper-
ature and humidity
The wear of individual components of the
brake system, such as the brake pads/linings
or brake discs, depends on the individual driv-
ing style and operating conditions.
Because of this, it is impossible to state a
mileage that will be valid under all circum-
stances. An aggressive driving style will lead
to high wear. Tyre grip
G
Risk of accident
Whereas the vehicle can be fully controlled
at a certain speed on dry roads, you must
reduce your speed on wet or icy roads to
achieve the same road safety. Otherwise
you could cause an accident.
Pay particular attention to the road condi-
tions at temperatures around freezing
point.
If ice has formed on the road surface (e.g.
from
fog), a light film of water rapidly forms
on the ice when you brake, considerably
reducing tyre grip. Drive with particular
care in such weather conditions. Operation
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