2005 MERCEDES-BENZ C320 tires

268 OperationDriving instructionsTires
Treadwear indicators (TWI) are required by
law. These indicators are located in six
places on the tread circumference and
become visible at a tread depth of
approximately
1/16
in (1.6 mm), at which
point the tire is considered worn and
should be replaced.The treadwear indicator appears as a solid
band across the tread.
Specified tire pressures must be main-
tained. This applies particularly if the tires
are subjected to high loads (e.g. high
speeds, heavy loads, high ambient temper-
atures).
Hydroplaning
Depending on the depth of the water layer
on the road, hydroplaning may occur, even
at low speeds and with new tires. Reduce
vehicle speed, avoid track grooves in the
road and apply brakes cautiously in the
rain.
Warning!
G
If you feel a sudden significant vibration or
ride disturbance, or you suspect that possi-
ble damage to your vehicle has occurred,
you should turn on the hazard warning flash-
ers, carefully slow down, and drive with cau-
tion to an area which is a safe distance from
the road.
Inspect the tires and the vehicle underbody
for possible damage. If the vehicle or tires
appear unsafe, have it towed to the nearest
Mercedes-Benz Center or tire dealer for
repairs.
Warning!
G
Although the applicable federal motor
vehicle safety laws consider a tire to be
worn when the treadwear indicators (TWI)
become visible at approximately
1/16in
(1.6 mm), we recommend that you do not
allow your tires to wear down to that level.
As tread depth approaches
1/8in (3 mm),
the adhesion properties on a wet road are
sharply reduced.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
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. Continued
driving with a flat tire or driving at high
speed with a flat tire will cause excessive
heat build-up and possibly a fire.

269 Operation
Driving instructions
Tire traction
The safe speed on a wet, snow covered or
icy road is always lower than on a dry road.
You should pay particular attention to the
condition of the road whenever the outside
temperatures are close to the freezing
point.
Mercedes-Benz recommends M+S rated
radial-ply tires with a minimum tread depth
of approximately
1/6in (4 mm) on all four
wheels for the winter season to ensure
normal balanced handling characteristics.
On packed snow, they can reduce your
stopping distance compared to summer
tires. Stopping distance, however, is still considerably greater than when the road is
not covered with snow or ice. Exercise ap-
propriate caution.
Tire speed rating
Regardless of the tire speed rating, local
speed limits should be obeyed. Use
prudent driving speeds appropriate to
prevailing conditions.
Warning!
G
If ice has formed on the road, tire traction
will be substantially reduced. Under such
weather conditions, drive, steer and brake
with extreme caution.
!Avoid spinning of one drive wheel. This
may cause serious damage to the
drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
Warning!
G
Even when permitted by law, never operate
a vehicle at speeds greater than the maxi-
mum 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.

270 OperationDriving instructionsC 230 Kompressor (Canada only),
C240, C2404MATIC,
C 320 (USA only), C 320 4MATIC
Your vehicle is factory equipped with
“H”-rated tires, which have a speed rating
of 130 mph (210 km/h).
An electronic speed limiter prevents your
vehicle from exceeding a speed of
130 mph (210 km/h).
C230KompressorSport, C320Sport
Your vehicle is factory equipped with
“W”-rated tires, which have a speed rating
of 168 mph (270 km/h).
An electronic speed limiter prevents your
vehicle from exceeding a speed of
130 mph (210 km/h).C55AMG
Your vehicle is factory equipped with
“Y”-rated tires, which have a speed rating
of 186 mph (300 km/h).
An electronic speed limiter prevents your
vehicle from exceeding a speed of
155 mph (250 km/h).
Winter driving instructions
The most important rule for slippery or icy
roads is to drive sensibly and to avoid
abrupt acceleration, braking and steering
maneuvers. Do not use the cruise control
system under such conditions.
When the vehicle is in danger of skidding,
move gear selector lever to positionN or in
case of manual transmission declutch.
Try to keep the vehicle under control by
corrective steering action.
iFor information on tire speed rating for
winter tires, see “Winter tires”
(page 290).
iFor information on driving with snow
chains, see “Snow chains”
(page 291).
Warning!
G
On slippery road surfaces, never downshift
in order to obtain braking action. This could
result in drive wheel slip and reduced
vehicle control. Your vehicle’s ABS will not
prevent this type of control loss.

286 OperationTires and wheelsSee an authorized Mercedes-Benz Center
for information on tested and
recommended rims and tires for summer
and winter operation. They can also offer
advice concerning tire service and
purchase.
Retreaded tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on
retreads. Mercedes-Benz can therefore
not assure the operating safety of the
vehicle when such tires are used.
See an authorized Mercedes-Benz Center
for information on tested and
recommended rims and tires for summer
and winter operation.
Important guidelines

Only use sets of tires and rims of the
same type and make.


Tires must be of the correct size for the
rim.


Break in new tires for approximately
60 miles (100 km) at moderate
speeds.


Regularly check the tires and rims for
damage. Dented or bent rims can
cause tire pressure loss and damage to
the tire beads.


If vehicle is heavily loaded, check tire
pressure and correct as required.


Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths under
1/8in (3 mm).


When replacing individual tires, you
should mount new tires on the front
wheels first (on vehicles with
same-sized wheels all around).
Warning!
G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. See an authorized
Mercedes-Benz Center for further informa-
tion. If incorrectly sized rims and tires are
mounted:

The wheel brakes or suspension
components can be damaged.


The correct operating clearance of the
wheels and the tires are no longer
guaranteed.
Warning!
G
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can
result in the bolts loosening and possibly an
accident.

287 Operation
Tires and wheels
Life of tire
The service life of a tire is dependent upon
varying factors including but not limited to:

Driving style


Tire pressure


Distance driven
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 tire rotation.
Checking tire inflation pressure
Correct the tire pressure only when tires
are cold.
Regularly check your tire pressure at
intervals of no more than 14 days.
If the tires are warm you should only
correct the tire pressure if it is too low for
current operating conditions.
A table on the fuel filler flap lists the
specified tire inflation pressures for warm
and cold tires as well as for various
operating conditions.
Warning!
G
Tires and spare tire should be replaced after
six years, regardless of the remaining tread.!Keep unmounted tires in a cool, dry
place with as little exposure to light as
possible. Protect tires from contact
with oil, grease and gasoline.
Warning!
G
If the tire pressure drops repeatedly:

Check the tires for punctures from
foreign objects.


Check to see whether air is leaking from
the valves or from around the rim.

288 OperationTires and wheels
Tire pressure changes by approx. 1.5 psi
(0.1 bar) per 18°F (10°C) of air tempera-
ture change. Keep this in mind when
checking tire pressure where the tempera-
ture is different from the outside tempera-
ture.
Tire temperature and tire pressure are also
increased while driving, depending on the
driving speed and the tire load.
Check the spare tire periodically for condi-
tion and inflation. Spare tires will age and
b e c o m e w o r n o v e r t i m e e v e n i f n e v e r u s e d ,
and thus should be inspected and replaced
when necessary.
iThe pressures listed for light loads are
minimum values offering high driving
comfort.
Increased inflation pressures listed for
heavier loads may also be used for light
loads. These higher pressures produce
favorable handling characteristics. The
ride of the vehicle, however, will be
somewhat harder. Never exceed the
max. values or inflate tires below the
min. values listed in the fuel filler flap.
Warning!
G
Follow recommended inflation pressures.
Do not overinflate tires. Overinflated tires
can result in sudden deflation (blowout)
because they are more likely to become
punctured 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.
Do not overload the tires by exceeding the
specified vehicle capacity weight (as indi-
cated by the label on the pillar in the driver’s
door opening). Overloading the tires can
overheat them, possibly causing a blowout.

289 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 287).
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 287).
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 329) and
(
page 353).
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.

290 OperationWinter drivingBefore the onset of winter, have your
vehicle winterized at an authorized
Mercedes-Benz Center. This service
includes:

Check of anticorrosion and antifreeze
concentration.


Addition of cleaning concentrate to the
water of the windshield and headlamp
cleaning system. Add MB Concentrate
“S” to a premixed windshield washer
solvent/antifreeze which is formulated
for below freezing temperatures
(page 396).


Battery test. Battery capacity drops
with decreasing ambient temperature.
A well charged battery helps to make
sure that the engine can be started,
even at low ambient temperatures.


Tire change. Mercedes-Benz recom-
mends M+S rated radial-ply tires with a
minimum tread depth of approximately 1/6in (4 mm) on all four wheels for the
winter season.
Winter tires
Always use winter tires at temperatures
below 45°F (7°C) and whenever wintry
road conditions prevail. Use of winter tires
is the only way to achieve the maximum
effectiveness of the ABS, ESP and 4MATIC
in winter operation.
For safe handling, make sure that all
mounted winter tires are of the same make
and have the same tread design.Always observe the speed rating of the
winter tires installed on your vehicle. If the
maximum speed for which your tires are
rated is below the speed rating of your
vehicle, you must place a notice to this
effect where it will be seen by the driver.
Such notices are available from your tire
dealer or from any authorized
Mercedes-Benz Center.Warning!
G
Winter tires with a tread depth under
1/6in
(4 mm) must be replaced. They are no
longer suitable for winter operation.
Warning!
G
If you use your spare tire when winter tires
are fitted on the other wheels, be aware that
the difference in tire characteristics may
very well impair turning stability and that
overall driving stability may be reduced.
Adapt your driving style accordingly.
Have the spare tire replaced with a winter
tire at the nearest authorized
Mercedes-Benz Center.