Storing tires
! Keep unmounted tires in a cool, dry place
with as little exposure to light as possible.
Protect tires from contact with oil, grease
and fuels.
Cleaning tires
! 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.
Uniform Tire Quality Grading
Standards
The Uniform Tire Quality Grading is a U.S.
Government requirement designed to give
drivers consistent and reliable information
regarding tire performance. Tire
manufacturers are required to grade tires
based on three performance factors:
treadwear :, traction ;, and temperature
resistance =. Although not a Government of
Canada requirement, all tires made for sale in
North America have these grades branded on
the sidewall.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
Quality grades can be found, where
applicable, on the tire sidewall between tread
shoulder and maximum section width. For
example:
TreadwearTractionTemperature200AAA
All passenger car tires must conform to
federal safety requirements in addition to
these grades.
Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified
U.S. Government test course. For example, a
tire graded 150 would wear one and one-half
(1 1/2) times as well on the government
course as a tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm due to variations in driving habits,
service practices and differences in road
characteristics and climate.
Traction
GWarning!
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
The traction grades, from highest to lowest,
are AA, A, B, and C. Those grades represent
the tire’s ability to stop on wet pavement as
measured under controlled conditions on
specified government test surfaces of asphalt
and concrete. A tire marked C may have poor
traction performance.
GWarning!
If ice has formed on the road, tire traction will
be substantially reduced. Under such weather
conditions, drive, steer and brake with
extreme caution.
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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
Tire type code
Tire type code ? may, at the option of the
manufacturer, be used as a descriptive code
for identifying significant characteristics of
the tire.
Date of manufacture
The date of manufacture A identifies the
week and year of manufacture.
The first two figures identify the week,
starting with “01” to represent the first full
week of the calendar year. The second two
figures represent the year.
For example, “3208” represents the 32nd
week of 2008.
Tire ply material
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
This marking tells you about the type of cord
and number of plies in the sidewall : and
under the tread ;.
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power seats,
radio, and heater, to the extent that these
items are available as factory-installed
equipment (whether installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire. Air
pressure is expressed in pounds per square
inch (psi), kilopascal (kPa), or bar.
Aspect ratio
Dimensional relationship between tire
section height and section width expressed
in percentage.
Bar
Metric unit for air pressure. There are
14.5038 pounds per square inch (psi) to
1 bar; there are 100 kilopascals (kPa) to 1 bar.
Bead
The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle has
been sitting for at least 3 hours or driven no
more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with standard
equipment including the maximum capacity
of fuel, oil, and coolant, and, if so equipped,
air conditioning and additional optional
equipment, but without passengers and
cargo.
DOT (Department of Transportation)
A tire branding symbol which denotes the tire
meets requirements of the U.S. Department
of Transportation.
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GAWR (Gross Axle Weight Rating)
The GAWR is the maximum permissible axle
weight. The gross vehicle weight on each axle
must never exceed the GAWR for the front
and rear axle indicated on the certification
label located on the driver’s door B-pillar.
GVW (Gross Vehicle Weight)
The GVW comprises the weight of the vehicle
including fuel, tools, spare wheel, installed
accessories, passengers and cargo and, if
applicable, trailer tongue load. The GVW must
never exceed the GVWR indicated on the
certification label located on the driver’s door
B-pillar.
GVWR (Gross Vehicle Weight Rating)
This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the vehicle including all options, passengers,
fuel, and cargo and, if applicable, trailer
tongue load). It is indicated on the
certification label located on the driver’s door
B-pillar.
Kilopascal (kPa)
Metric unit for air pressure. There are 6.9 kPa
to 1 psi; another metric unit for air pressure
is bar. There are 100 kilopascals (kPa) to
1 bar.
Load index
Numerical code associated with the
maximum load a tire can support.
Maximum load rating
The maximum load in kilograms and pounds
that can be carried by the tire.
Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
total load limit, and production options
weight.
Maximum permissible tire inflation
pressure
This number is the greatest amount of air
pressure that should ever be put in the tire.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by 68 kilograms
(150 lb).
Occupant distribution
The distribution of occupants in a vehicle at
their designated seating positions.
Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.
PSI (Pounds per square inch)
A standard unit of measure for air pressure.
Recommended tire inflation pressure
The recommended tire inflation pressure for
normal driving conditions is listed on the Tire
and Loading Information placard located on
the driver’s door B-pillar. It provides best
handling, tread life and riding comfort.
Supplemental information pertaining to
special driving situations can be found on the
tire inflation pressure label on the inside of
the fuel filler flap.
Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
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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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obstacles. If there are any floormats or
carpets in the footwell, make sure that the
pedals still have sufficient clearance.
During sudden driving or braking maneuvers,
the objects could get caught between the
pedals. You could then no longer brake or
accelerate. This could lead to accidents and
injury.
Power assistance
GWarning!
There is no power assistance for the steering
and the brake when the engine is not running.
Steering and braking requires significantly
more effort and you could lose control of the
vehicle and cause an accident as a result.
Do not turn off the engine while the vehicle is
in motion.
Brakes
Downhill grades
! When driving down long and steep
grades, relieve the load on the brakes by
shifting into a lower gear to use the
engine’s braking power. This helps prevent
overheating of the brakes and reduces
wear.
When using the engine’s braking power, a
drive wheel may not spin for an extended
period of time, e.g. on slippery road
surfaces. This may cause serious damage
to the drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
Continuous or hard braking
GWarning!
Resting your foot on the brake pedal will
cause excessive and premature wear of the
brake pads.
It can also result in the brakes overheating,
thereby significantly reducing their
effectiveness. It may not be possible to stop
the vehicle in sufficient time to avoid an
accident.
After hard braking, it is advisable to drive on
for some time, rather than immediately park,
so that the air stream will cool down the
brakes faster.
Wet roadsGWarning!
After driving in heavy rain for some time
without applying the brakes or through water
deep enough to wet brake components, the
first braking action may be somewhat
reduced and increased pedal pressure may be
necessary to obtain expected brake effect.
Maintain a safe distance from vehicles in
front.
To help prevent brake disk corrosion after
driving on wet or salt-covered roads, it is
advisable to brake the vehicle with
considerable force prior to parking. The heat
generated serves to dry the brakes.
Salt-covered roads
GWarning!
A layer of salt on the brake discs and the brake
linings may cause a delay in the braking
effect, resulting in a significantly increased
braking distance, which could lead to an
accident.
To avoid this danger, you should:
R occasionally brake carefully when you are
driving on salt-covered roads, so that any
layer of salt that may have built up on the
brake discs and the brake linings is
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removed without putting other road users
at risk
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
Brake service
! The brake fluid level in the reservoir may
be too low if the red brake warning lamp in
the instrument cluster comes on while the
engine is running and an acoustic warning
sounds. Observe additional messages in
the multifunction display that may appear.
Brake pad wear or a leak in the system may
be the reason for low brake fluid in the
reservoir.
Have the brake system inspected
immediately. Contact an authorized
Mercedes-Benz Center.
All checks and service work on the brake
system should be carried out by qualified
technicians only. Contact an authorized
Mercedes-Benz Center.
Only install brake pads and use brake fluid
recommended by Mercedes-Benz.
GWarning!
If other than recommended brake pads are
installed, or other than recommended brake
fluid is used, the braking properties of the
vehicle can be degraded to an extent that safe
braking is substantially impaired. This could
result in an accident.
! Vehicles with 4MATIC:
Only conduct operational or performance
tests on a two-axle dynamometer. If such
tests are necessary, contact an authorized
Mercedes-Benz Center. You could
otherwise seriously damage the brake
system or the transfer case which is not
covered by the Mercedes-Benz Limited
Warranty.
! Vehicles with 4MATIC:
Because the ESP ®
operates automatically,
the engine and ignition must be shut off
(SmartKey in starter switch position 0 or
1 or KEYLESS-GO start/stop button in
position 0 or 1) when the parking brake is
being tested on a brake test dynamometer.
Active braking action through the ESP ®
may otherwise seriously damage the brake
system which is not covered by the
Mercedes-Benz Limited Warranty.
! Vehicles without 4MATIC:
Because the ESP ®
operates automatically,
the engine and ignition must be shut off
(SmartKey in starter switch position 0 or
1 or KEYLESS-GO start/stop button in
position 0 or 1) when the parking brake is
being tested on a brake test dynamometer
or the vehicle is being towed with the front
axle raised.
Active braking action through the ESP ®
may otherwise seriously damage the brake
system which is not covered by the
Mercedes-Benz Limited Warranty.
If your brake system is only subjected to
moderate loads, you should occasionally test
the effectiveness of the brakes by applying
above-normal braking pressure at higher
speeds. This will also enhance the grip of the
brake pads.GWarning!
Make sure not to endanger any other road
users when carrying out these braking
maneuvers.
Refer to the description of the Brake Assist
System (BAS) ( Y page 61).
High-performance brake system
The high-performance brake system is only
available on C 63 AMG.
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