2007 MERCEDES-BENZ CLK350 fuel

326 Operation
Tires and wheels
Direction of rotation
Unidirectional tires offer added advan-
tages, such as better hydroplaning perfor-
mance. To benefit, however, you must
make sure the tires rotate in the direction
specified.
An arrow on the sidewall indicates the
intended direction of rotation (spinning) of
the tire.Loading the vehicle
A label on your vehicle shows how much
weight it may properly carry.

The Tire and Loading Information
placard can be found on the driver’s
door B-pillar. This placard tells you im-
portant information about the number
of people that can be in the vehicle and
the total weight that can be carried in
the vehicle. It also contains information
on the proper size and recommended
tire inflation pressures for the original
equipment tires on your vehicle.

The certification label found on the
driver’s door B-pillar tells you about the
gross weight capacity of your vehicle,
called the Gross Vehicle Weight Rating
(GVWR). The GVWR includes the weight
of the vehicle, all occupants, fuel and
cargo. The certification label also tells
you about the front and rear axle weight capacity,
called the Gross Axle Weight Rating
(GAWR). The GAWR is the total allow-
able weight that can be carried by a sin-
gle axle (front or rear). Never exceed
the GVWR or GAWR for either the front
axle or rear axle.
1Driver’s door B-pillar
Following is a discussion on how to work
with the information contained on the plac-
ard with regards to loading your vehicle.
iSpare wheels may be mounted against the
direction of rotation (spinning) even with a unidi-
rectional tire for temporary use only until the reg-
ular drive wheel has been repaired or replaced.
Always observe and follow applicable temporary
use restrictions and speed limitations indicated
on the spare wheel.

331 Operation
Tires and wheels
Recommended tire inflation pressure
Your vehicle is equipped with a Tire and
Loading Information placard located on
the driver’s door B-pillar (
page 326).The tire inflation pressure should be
checked regularly and should only be ad-
justed on cold tires. The tires can be con-
sidered cold if the vehicle has been parked
for at least three hours or driven less than
one mile (1.6 km).
Follow recommended cold tire inflation
pressures listed on placard.
Keeping the tires properly inflated
provides the best handling, tread life and
riding comfort.
In addition to the tire placard on the
driver’s door B-pillar, also consult the fuel
filler flap for any additional information
pertaining to special driving situations. For
more information, see “Important notes on
tire inflation pressure” (
page 332).Placard
1Tire and Loading Information placard
with recommended cold tire inflation
pressures
The placard lists the recommended cold
tire inflation pressures for maximum load-
ed vehicle weight. The tire inflation pres-
sures listed apply to the tires installed as
original equipment.
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 over-
heated.
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.
iData shown on placard example are for
illustration purposes only. Tire data is specific to
each vehicle and may vary from data shown in
the illustration below. Refer to placard on vehicle
for actual data specific to your vehicle.

332 Operation
Tires and wheels
Important notes on tire inflation
pressure
Tire temperature and tire inflation pressure
are also increased while driving, depending
on the driving speed and the tire load.If you will be driving your vehicle at high
speeds of 100 mph (160 km / h) or higher,
where it is legal and conditions allow,
consult the placard on the inside of the fuel
filler flap on how to adjust the cold tire in-
flation pressure. If you do not adjust the
tire inflation pressure, excessive heat can
build up and result in sudden tire failure.
Be sure to readjust the tire inflation
pressure for normal driving speeds. You
should wait until the tires are cold before
adjusting the tire inflation pressure. Some vehicles may have supplemental tire
pressure information for vehicle loads less
than the maximum loaded vehicle condi-
tion. If such information is provided, it can
be found on the placard located on the in-
side of the fuel filler flap.
Tire inflation pressure changes by approxi-
mately 1.5 psi (0.1 bar) per 18°F (10°C) of
air temperature change. Keep this in mind
when checking tire inflation pressure
where the temperature is different from
the outside temperature.
Warning!G
If the tire inflation pressure repeatedly
drops:

Check the tires for punctures from
foreign objects.

Check to see whether air is leaking from
the valves or from around the rim.
iDriving comfort may be reduced when the
tire inflation pressure is adjusted to the value for
speeds above 100 mph (160 km / h) as specified
on the placard located on the inside of the fuel
filler flap.

333 Operation
Tires and wheels
Checking tire inflation pressure
Regularly check your tire inflation pressure
at least once a month.
Check and adjust the tire inflation
pressure when the tires are cold. The tires
can be considered cold if the vehicle has
been parked for at least three hours or
driven less than one mile (1.6 km).
If you check the tire inflation pressure
when the tires are warm (the vehicle has
been driven for several miles or sitting less
than three hours), the reading will be
approximately 4 psi (0.3 bar) higher than
the cold reading. This is normal. Do not let
air out to match the specified cold tire in-
flation pressure. Otherwise, the tire will be
underinflated.Checking tire inflation pressure
manually
Follow the steps below to achieve correct
tire inflation pressure:
Remove the cap from the valve on one
tire.
Firmly press a tire gauge onto the
valve.
Read tire inflation pressure on tire
gauge and check against the recom-
mended tire inflation pressure on the
placard on the driver’s door B-pillar
(
page 331). If necessary, add air to
achieve the recommended tire inflation
pressure.
Install the valve cap.
Repeat this procedure for each tire.
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 over-
heated.
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.
Do not overload the tires by exceeding the
specified load limit as indicated on the plac-
ard on the driver’s door B-pillar. Overloading
the tires can overheat them, possibly caus-
ing a blowout.
iIf you have overfilled the tire, release tire in-
flation pressure by pushing the metal stem of the
valve with e.g. a tip of a pen. Then recheck the
tire inflation pressure with the tire gauge.

334 Operation
Tires and wheels
Run Flat Indicator*
U.S. vehicles: The Run Flat Indicator is only
available in conjunction with the
MOExtended system* (
page 336).
While the vehicle is being driven, the Run
Flat Indicator monitors the set tire inflation
pressures by evaluating each wheel’s rota-
tional speed. This allows the system to de-
tect a significant loss of pressure in a tire.
If a wheel’s rotational speed changes due
to falling tire inflation pressure, you will
see a corresponding warning message in
the multifunction display.
The Run Flat Indicator may function in a re-
stricted manner or with a delay if:

snow chains are mounted to the
vehicle

in presence of ice and snow

you are driving on a loose surface (e.g.
sand or gravel)

you are driving in a very sporty manner
(involving rapid acceleration or high
speeds in curves)

you are driving with very heavy cargo
loaded
Warning!G
When the multifunction display shows the
message
Tire pressure Check tires,
one or more of your tires is significantly un-
der-inflated. You should stop and check
your tires as soon as possible, and inflate
them to the proper tire inflation pressure as
indicated on the vehicle’s tire information
placard. Driving on a significantly under-in-
flated tire causes the tire to overheat and
can lead to tire failure. Under-inflation also
reduces fuel efficiency and tire tread life,
and may affect the vehicle’s handling and
stopping ability. Each tire, including the
spare, should be checked monthly when
cold and set to the recommended tire infla-
tion pressure as specified in the vehicle
placard.
iThe recommended tire inflation pressures
for your vehicle can be found on the tire placard
located on the driver’s door B-pillar
(
page 326). The tire inflation pressures are
not listed in the Operator’s Manual.
Warning!G
The Run Flat Indicator does not provide a
warning for wrongly selected tire inflation
pressures. Always adjust tire inflation pres-
sure according to the placard on the driver’s
door B-pillar or fuel filler flap.
The Run Flat Indicator does not replace reg-
ular checks of the tire inflation pressures
since a gradual pressure loss in more than
one tires cannot be detected by the Run Flat
Indicator.
The Run Flat Indicator is not able to issue a
warning due to a sudden dramatic loss of
tire inflation pressure (e.g. tire blowout
caused by a foreign object). In this case
bring the vehicle to a halt by carefully apply-
ing the brakes and avoiding abrupt steering
maneuvers.

335 Operation
Tires and wheels
Reactivating the Run Flat Indicator
The tire inflation pressure monitor must be
reactivated in the following situations:

If you have changed the tire inflation
pressure

If you have replaced the wheels or tires

If you have installed new wheels or
tires
Using the tire placard on the driver’s
door B-pillar or, if available, the inside
of the fuel filler flap, make sure the tire
inflation pressure of all four tires is
correct.
Switch on the ignition (page 36).
Make sure the standard display menu
appears in the multifunction display
(
page 145).
Press buttonk orj repeatedly
until the following message appears in
the multifunction display:
Press the reset button in the
instrument cluster (
page 136).
The following message will appear in
the multifunction display:
Restart
Run Flat Indicator?
Cancel
Yes
If you wish to confirm activation:
Press buttonæ.
The following message will appear in
the multifunction display:
Run Flat Indicator
restarted
After a certain “learning phase”, the Run
Flat Indicator checks the set pressure val-
ues for all four tires.
If you wish to cancel activation:
Press buttonç.
or
Wait until the message
Restart
Run Flat Indicator?
Cancel
Yes
disappears.
Warning!G
The Run Flat Indicator can only warn you in
a reliable manner if you have set the correct
tire inflation pressures for each tire.
If an incorrect tire inflation pressure was
set, the system will monitor the pressure
according to the incorrect value.

336 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*
(
page 334).
For information on driving in case of pres-
sure loss in one or more tires (emergency
mode), see the “Practical hints” section
(
page 446).
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.

344 Operation
Tires and wheels
Maximum tire inflation pressure
1Maximum permissible tire inflation
pressure
This is the maximum permissible tire
inflation pressure for the tire.Always follow the recommended tire
inflation pressure (
page 331) for proper
tire inflation. Uniform Tire Quality Grading Standards (U.S. vehicles)
Tire manufacturers are required to grade
tires based on three performance
factors: treadwear, traction and
temperature resistance.
1Treadwear
2Traction
3Temperature resistance
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
Warning!G
Never exceed the max. tire inflation
pressure. Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and / or unevenly, adverse-
ly affect handling and fuel economy, and are
more likely to fail from being overheated.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride com-
fort, wear unevenly, increase stopping dis-
tance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road de-
bris, potholes etc.