2005 MERCEDES-BENZ CLK320 COUPE warning

317 Operation
Tires and wheels
Tire care and maintenance
Regularly check your tire inflation pressure
at least once a month. For more informa-
tion on checking tire inflation pressure see
“Recommended tire inflation pressure”
(page 325).Tire inspection
Every time you check your tire inflation
pressure, you should also inspect your
tires for the following:


excessive tread wear (
page 318)


cord or fabric showing through the
tire’s rubber


bumps, bulges, cuts, cracks or splits in
the tread or side of the tire
Replace the tire if you find any of the above
conditions.
Make sure you also inspect the spare tire
periodically for condition and inflation.
Spare tires will age and become worn over
time even if never used, and thus should be
inspected and replaced when necessary.Life of tire
The service life of a tire is dependent upon
varying factors including but not limited to:


Driving style


Tire inflation pressure


Distance driven
Warning!
G
Regularly check the tires for damage. Dam-
aged tires can cause tire inflation pressure
loss. As a result, you could lose control of
your vehicle.
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
Warning!
G
Tires and spare tire should be replaced after
six years, regardless of the remaining tread.

318 OperationTires and wheelsTread depth
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).
Tread wear 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 approx-
imately
1/16
in (1.6 mm), at which point
the tire is considered worn and should be
replaced.
Recommended minimum tire tread depth:


Summer tires
1/8in (3 mm)


Winter tires
1/6in (4 mm)
1TWI (T
read W
ear I
ndicator)
The tread wear indicator appears as a solid
band across the tread.Storing tires
Cleaning tires
Warning!
G
Although the applicable federal motor safety
laws consider a tire to be worn when the
tread wear indicators (TWI) become visible
at approximately
1/16in (1.6 mm), we rec-
ommend 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 re-
duced.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
!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.!Never use a round nozzle to power
wash tires. The intense jet of water can
result in damage to the tire.
Always replace a damaged tire.

320 OperationTires and wheels1Driver’s door B-pillar
Following is a discussion on how to work
with the information contained on the two
placards with regards to loading your vehi-
cle.Tire and Loading Information
Your vehicle is equipped with either the
Tire and Loading Information placard
(Example A) or the Vehicle Tire Information
placard (Example B). Placard (Example A)
1Load limit information on the Tire and
Loading Information placard
The placard showing the load limit informa-
tion is located on the driver’s door B-pillar.
If your vehicle is equipped with the Tire and
Loading Information placard (Example A),
locate the statement “The combined
weight of occupants and cargo should
never exceed XXX kilograms or XXX lbs.”
on this placard. The combined weight of all
occupants, cargo / luggage and trailer
tongue load (if applicable) should never
exceed the weight referenced in that
statement.
Warning!
G
Do not overload the tires by exceeding the
specified load limit or vehicle capacity
weight as indicated on the placard on the
driver’s door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also
result in handling or steering problems, or
brake failure.iData shown on placard examples is for
illustration purposes only. Load limit
data is specific to each vehicle and may
vary from data shown in the illustra-
tions below. Refer to placard on vehicle
for actual data specific to your vehicle.

325 Operation
Tires and wheels
Recommended tire inflation pressure
Your vehicle is equipped with either the
Tire and Loading Information placard
(Example A) or the Vehicle Tire Information
placard (Example B) located on the driver’s
door B-pillar (
page 320).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 326).Placard (Example A)
1Tire and Loading Information placard
with recommended cold tire inflation
pressures
Placard (Example A) lists the recommend-
ed cold tire inflation pressures for maxi-
mum loaded vehicle weight. The tire
inflation pressures 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 examples is for
illustration purposes only. Tire data is
specific to each vehicle and may vary
from data shown in the illustrations
below. Refer to placard on vehicle for
actual data specific to your vehicle.

326 OperationTires and wheelsPlacard (Example B)
1Vehicle Tire Information placard with
recommended cold tire inflation
pressures
Placard (Example B) lists the recommend-
ed cold tire inflation pressures for maxi-
mum loaded vehicle weight. The tire
inflation pressures listed apply to the tires
installed as original equipment.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.
iPlacard (Example B) may list
recommended cold tire inflation
pressures for different vehicle loads.
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.

327 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 325). If necessary, add air to
achieve the recommended tire inflation
pressure.

Install the valve cap.

Repeat this procedure for each tire.Potential problems associated with
underinflated and overinflated tires
Underinflated tire inflation pressure
Underinflated tires can:


cause excessive and uneven tire wear


adversely affect fuel economy


lead to tire failure from being
overheated


adversely affect handling
characteristics
iIf you have overfilled the tire, release
tire inflation 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.
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.

328 OperationTires and wheelsOverinflated tire inflation pressure
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
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 Quality Grading Standards
(
page 336)
2DOT, Tire Identification Number (TIN)
(page 333)
3Maximum tire load (
page 334)
4Maximum tire inflation pressure
(
page 335)
5Manufacturer
6Tire ply material (
page 337)
7Tire size designation, load and speed
rating (
page 329)
8Load identification (
page 332)
9Tire name
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.
iFor illustration purposes only. Actual
data on tires is specific to each vehicle
and may vary from data shown in above
illustration.
For more information, see “Rims and
tires” (
page 439).

330 OperationTires and wheelsRim diameter
The rim diameter4 (
page 329) is the
diameter of the bead seat, not the
diameter of the rim edge. Rim diameter is
indicated in inches (in).
Tire load rating
The tire load rating5 (page 329) 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 334) 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 332).
Warning
G
The tire load rating must always be at least
half of the GAWR (
page 338) of your vehi-
cle. Otherwise, tire failure may be the result
which may cause an accident and/or seri-
ous 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 load limit or vehicle capacity
weight as indicated on the placard located
on the driver’s door B-pillar. Overloading the
tires can overheat them, possibly causing a
blowout. Overloading the tires can also
result in handling or steering problems, or
brake failure.
iTire load rating5 (
page 329) and
Tire speed rating6 (page 329) are
also referred to as “service descrip-
tion”.