2010 MERCEDES-BENZ C300 4MATIC page 88

Tire care and maintenanceGWarning!
Regularly check the tires for damage.
Damaged 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 worn to minimum tread depth, or if
the tires have sustained damage, replace
them.
Check the tire inflation pressure at least once
a month. For more information on checking
tire inflation pressure, see “Recommended
tire inflation pressure” (Y page 230).
Tire inspection
Every time you check the tire inflation
pressure, you should also inspect your tires
for the following:
Rexcessive treadwear (Y page 243)
Rcord or fabric showing through the tire’s
rubber
Rbumps, 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
GWarning!
Tires and spare tire should be replaced after
6 years, regardless of the remaining tread.
The service life of a tire is dependent upon
varying factors including but not limited to:
RDriving style
RTire inflation pressure
RDistance driven
Tread depth GWarning!
Although the applicable federal motor vehicle
safety laws consider a tire to be worn when
the treadwear indicators (TWI) become visible
at approximately 1/16 in (1.6 mm), we
recommend that you do not allow your tires
to wear down to that level. As tread depth
approaches 1/8 in (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.
Do not allow your tires to wear down too far.
Adhesion properties on wet roads are sharply
reduced at tread depths of less than 1/8 in
(3 mm).
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 approximately1/16 in (1.6 mm), at which point the tire is
considered worn and should be replaced.
The recommended minimum tire tread depth
for summer tires is 1/8 in (3 mm). The
recommended minimum tire tread depth for
winter tires is 1/6 in (4 mm).
Treadwear indicator : appears as a solid
band across the tread.
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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
temperature is close to the freezing point.
Mercedes-Benz recommends winter tires
( Y page 252) with a minimum tread depth of
approximately 1
/ 6 in (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
appropriate caution.
! Avoid spinning of a drive wheel. This may
cause serious damage to the drivetrain
which is not covered by the Mercedes-Benz
Limited Warranty.
Temperature GWarning!
The temperature grade for this tire is
established for a tire that is properly inflated
and not overloaded. Excessive speed,
underinflation, or excessive loading, either
separately or in combination, can cause
excessive heat build-up and possible tire
failure.
The temperature grades are A (the highest),
B, and C, representing the tire’s resistance to
the generation of heat and its ability to
dissipate heat when tested under controlled
conditions on a specified indoor laboratory
test wheel. Sustained high temperature can
cause the material of the tire to degenerate
and reduce tire life, and excessive
temperature can lead to sudden tire failure.
The grade C corresponds to a level of
performance which all passenger car tires
must meet under the Federal Motor Vehicle
Safety Standard No. 109. Grades B and A
represent higher levels of performance on the
laboratory test wheel than the minimum
required by law.
Rotating tires
GWarning!
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.
GWarning!
Have the tightening torque checked after
changing a wheel. Wheels could become
loose if not tightened with a torque of
96 lb-ft (130 Nm).
Only use genuine Mercedes-Benz wheel bolts
specified for your vehicle’s rims.
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 front-to-rear rotation
pattern that will maintain the intended
rotation (spinning) direction of the tire
( Y page 242).
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
configuration, tires can be rotated according
to the tire manufacturer’s recommended
intervals 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 necessary, according
to the degree of tire wear. The same rotation
(spinning) direction must be maintained.
Rotate tires before the characteristic tire
wear pattern becomes visible (shoulder wear
on front tires and tread center wear on rear
tires).
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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 “Flat
tire” (Y page 317).
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:
:Uniform Tire Quality Grading Standards
(Y page 244)
;DOT, Tire Identification Number
(Y page 249)
=Maximum tire load (Y page 242)?Maximum tire inflation pressure
(Y page 237)
AManufacturerBTire ply material (Y page 250)CTire size designation, load and speed
rating (Y page 246)
DLoad identification (Y page 249)ETire nameiFor 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”
(Y page 344).
Tire size designation, load and speed
rating
:Tire width;Aspect ratio in %=Radial tire code?Rim diameterALoad index BSpeed symbol
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
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.
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Letter “T” preceding the size designation:
Temporary spare tires which are high
pressure compact spares designed for
temporary emergency use only.
Tire width
Tire width : indicates the nominal tire width
in millimeters.
Aspect ratio
Aspect ratio ; 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
Tire code = indicates the tire construction
type. The “R” stands for radial tire type. Letter
“D” means diagonal 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” ( Y page 247).
Rim diameter
Rim diameter ? is the diameter of the bead
seat, not the diameter of the rim edge. The
rim diameter is indicated in inches (in).
Load indexGWarning!
The tire load rating must always be at least
half of the GAWR of your vehicle. Otherwise,
tire failure may be the result which may cause
an accident and/or serious injury to you or
others.
Always replace rims and tires with the same
designation, manufacturer and type as shown
on the original part.
GWarning!
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information 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.
Load index A is a numerical code associated
with the maximum load a tire can support.
For example, a load rating of 91 corresponds
to a maximum load of 1356 lb (615 kg) the
tire is designed to support. See also
“Maximum tire load” (Y page 242) where the
maximum load associated with the load index
is indicated in kilograms and lbs.
For additional information on the load index,
see “Load identification” ( Y page 249).
Speed symbol GWarning!
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 serious
personal injury and possible death, for you
and for others.
Regardless of the tire speed rating, local
speed limits should be obeyed. Use prudent
driving speeds appropriate to prevailing
conditions.
Speed symbol B indicates the approved
maximum speed (tire speed rating) for the
tire.
Summer tires
IndexSpeed ratingQup 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)Tires and wheels247Operation204_AKB; 5; 23, en-USd2ureepe,Version: 2.11.8.12009-07-16T17:54:06+02:00 - Seite 247Z

IndexSpeed ratingHup 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)ZR...Yup to 186 mph (300 km/h)ZR...(..Y)above 186 mph (300 km/h)ZRabove 149 mph (240 km/h)
RAt 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 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
load index A and speed symbol B.
If your tire includes “ZR” in the size
designation and no service description is
given, the tire manufacturer must be
consulted for the maximum speed
capability.
If a service description is given, the speed
capability 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
capability of the tire is limited to 186 mph
(300 km/h).
R 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 symbol in parenthesis 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 tiresIndexSpeed ratingQ M+S 18up to 100 mph (160 km/h)T M+S18up to 118 mph (190 km/h)H M+S 18up to 130 mph (210 km/h)V M+S18up to 149 mph (240 km/h)
i
Not all M+S rated tires provide special
winter performance. Make sure the tires
you use show M+S and the mountain/
snowflake imarking on the tire
sidewall. These tires meet specific snow
traction performance requirements of the
Rubber Manufacturers Association (RMA)
and the Rubber Association of Canada
(RAC) and have been designed specifically
for use in snow conditions.
An electronic speed limiter prevents your
vehicle from exceeding a speed of:
R All models except C 63 AMG:
130 mph (210 km/h)
R C 63 AMG:
155 mph (250 km/h)
R C 63 AMG with increased top speed:
174 mph (280 km/h)
The factory equipped tires on your vehicle
may have a tire speed rating above the
maximum speed permitted by the electronic
speed limiter.
Make sure your tires have the required tire
speed rating as specified for your vehicle in
the “Technical data” section ( Y page 344),
for example when purchasing new tires.
If you are uncertain about the correct reading
of the information given on a tire’s sidewall,
any authorized Mercedes-Benz Center will be
glad to assist you.
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Load identification
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
In addition to the load index, special load
identification : may be molded into the tire
sidewall following the letter designating the
speed symbol B (Y page 246).
RNo specification given: absence of any text
(like in above example) indicates a
standard load (SL) tire.
RXL or Extra Load: designates an extra load
(or reinforced) tire.
RLight Load: designates a light load tire.
RC, D, E: designates load range associated
with the maximum load a tire can carry at
a specified pressure.
DOT, Tire Identification Number (TIN)
U.S. tire regulations require each new tire
manufacturer or tire retreader to mold a TIN
into or onto a sidewall of each tire produced.
The TIN is a unique identifier. The TIN
facilitates efforts by tire manufactures to
notify purchasers in recall situations or other
safety matters concerning tires. It gives
purchasers the means to easily identify such
tires.
The TIN is comprised of “Manufacturer’s
identification mark” ;, “Tire size” =, “Tire
type code” ? and “Date of manufacture”
A.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
DOT (Department of Transportation)
Tire branding symbol : denotes that the tire
meets requirements of the U.S. Department
of Transportation.
Manufacturer’s identification mark
Manufacturer’s identification mark ;
denotes the tire manufacturer.
New tires have a mark with two symbols.
Retreaded tires have a mark with four
symbols. For more information on retreaded
tires, see (Y page 229).
Tire size
Code = indicates the tire size.
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Always use winter tires at temperatures
below 45‡ (7†) and whenever wintry road
conditions prevail. Not all M+S rated tires
provide special winter performance. Make
sure the tires you use show the mountain/
snowflake imarking on the tire sidewall.
These tires meet specific snow traction
performance requirements of the Rubber
Manufacturers Association (RMA) and the
Rubber Association of Canada (RAC) and
have been designed specifically for use in
snow conditions. Use of winter tires is the
only way to achieve the maximum
effectiveness of your vehicle’s driving safety
systems such as the ABS and the ESP ®
in
winter operation.
For safe handling, make sure all mounted
winter tires are of the same make and have
the same tread design.
For information on winter tires for your
vehicle model, see the “Technical data”
section ( Y page 344).
Always observe the speed rating of the winter
tires installed on your vehicle.
After installing winter tires:XCheck the tire inflation pressure and adjust
it if necessary ( Y page 232).XRestart the tire pressure loss warning
system ( Y page 233) or the Advanced Tire
Pressure Monitoring System (Y page 234).
Snow chains
! Some tire sizes do not leave adequate
clearance for snow chains. To help avoid
serious damage to your vehicle or tires,
make sure the use of snow chains is
permissible as specified in the “Technical
data” section of this Operator’s Manual.
Snow chains should only be driven on snow-
covered roads at speeds not to exceed
30 mph (50 km/h). Remove chains as soon
as possible when driving on roads without
snow.
Observe the following guidelines when using
snow chains:
R Use of snow chains is not permissible with
all wheel/tire combinations ( Y page 344).
R Use snow chains in pairs and on rear
wheels only. Follow the manufacturer’s
mounting instructions.
! If snow chains are mounted to the front
wheels, they may scrape against the body
or axle components. The tires or the vehicle
could be damaged as a result.
R Only use snow chains that are approved by
Mercedes-Benz. Any authorized Mercedes-
Benz Center will be glad to advise you on
this subject.
R Use of snow chains may be prohibited
depending on location. Always check local
and state laws before installing snow
chains.
R Do not use snow chains on the spare wheel.
i When driving with snow chains, you may
wish to switch off the ESP ®
(Y page 62)
before setting the vehicle in motion. This
will improve the vehicle’s traction.
Winter driving instructions
GWarning!
If the vehicle becomes stuck in snow, make
sure snow is kept clear of the exhaust pipe
and from around the vehicle with the engine
running. Otherwise, deadly carbon monoxide
(CO) gases may enter vehicle interior
resulting in unconsciousness and death.
To assure sufficient fresh air ventilation, open
a window slightly on the side of the vehicle
not facing the wind.
GWarning!
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
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Indicated temperatures just above the
freezing point do not guarantee that the road
surface is free of ice. The road may still be icy,
especially in wooded areas or on bridges.GWarning!
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 loss of control.
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, shift
the automatic transmission to neutral
position N or declutch in case of manual
transmission. Try to keep the vehicle under
control by corrective steering action.
i For information on driving with snow
chains, see “Snow chains” ( Y page 253).
Road salts and chemicals can adversely
affect braking efficiency. Increased pedal
force may become necessary to produce the
normal brake effect.
Depressing the brake pedal periodically when
traveling at length on salt-strewn roads can
bring road-salt-impaired braking efficiency
back to normal.
If the vehicle is parked after being driven on
salt-treated roads, the braking efficiency
should be tested as soon as possible after
driving is resumed.
GWarning!
Make sure not to endanger any other road
users when carrying out these braking
maneuvers.
Driving instructions
Drive sensibly – save fuel
To save fuel you should:
R Keep tires at the recommended inflation
pressures.
R Remove unnecessary loads.
R Remove roof rack when not in use.
R Allow engine to warm up under low load
use.
R Avoid frequent acceleration and
deceleration.
R Have all maintenance work performed at
the intervals specified in the Maintenance
Booklet and as required by the
Maintenance system. Contact an
authorized Mercedes-Benz Center.
Fuel consumption is also increased by driving
in cold weather, in stop-and-go traffic, on
short trips and in mountainous areas.
Drinking and driving
GWarning!
Drinking and driving and/or taking drugs and
driving are very dangerous combinations.
Even a small amount of alcohol or drugs can
affect your reflexes, perceptions and
judgment.
The possibility of a serious or even fatal
accident are greatly increased when you drink
or take drugs and drive.
Do not drink or take drugs and drive or allow
anyone to drive who has been drinking or
taking drugs.
Pedals
GWarning!
Make sure absolutely no objects are
obstructing the pedals’ range of movement.
Keep the driver’s footwell clear of all
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