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).
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 319).
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 233)
;DOT, Tire Identification Number
(Y page 238)
=Maximum tire load (Y page 231)?Maximum tire inflation pressure
(Y page 226)
AManufacturerBTire ply material (Y page 239)CTire size designation, load and speed
rating (Y page 236)
DLoad identification (Y page 238)ETire name
iFor 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 352).
Tires and wheels235Operation164_AKB; 7; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:07:36+02:00 - Seite 235Z
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.
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 237).
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 index
GWarning!
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.
236Tires and wheelsOperation
164_AKB; 7; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:07:36+02:00 - Seite 236
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 231) 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 238).
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)Hup 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)IndexSpeed ratingZR...(..Y)above 186 mph (300 km/h)ZRabove 149 mph (240 km/h)
R 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 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 tires
IndexSpeed ratingQ M+S 20up to 100 mph (160 km/h)T M+S20up to 118 mph (190 km/h)20
or M+S ifor winter tiresTires and wheels237Operation164_AKB; 7; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:07:36+02:00 - Seite 237Z
IndexSpeed ratingH M+S20up to 130 mph (210 km/h)V M+S20up to 149 mph (240 km/h)
iNot all M+S rated tires provide special
winter performance. Make sure the tires
you use show M+S and the mountain/
snowflakeimarking 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:
RAll models except ML 63 AMG:
130 mph (210 km/h)
RML 63 AMG:
155 mph (250 km/h)
RML 63 AMG with increased top speed:
171 mph (275 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 352),
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.
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 236).
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.
20or M+Sifor winter tires238Tires and wheelsOperation
164_AKB; 7; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:07:36+02:00 - Seite 238
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 218).
Tire size
Code = indicates the tire size.
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,
Tires and wheels239Operation164_AKB; 7; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:07:36+02:00 - Seite 239Z
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.
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.
GTW (Gross Trailer Weight)
The GTW is the weight of the trailer plus the
weight of all cargo, equipment, luggage etc.
loaded on the trailer.
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.
240Tires and wheelsOperation
164_AKB; 7; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:07:36+02:00 - Seite 240
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.
Sidewall
The portion of a tire between the tread and
the bead.
TIN (Tire Identification Number)
Unique identifier which facilitates efforts by
tire manufacturers to notify purchasers in
recall situations or other safety matters
concerning tires and 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”.
Tire ply composition and material used
This indicates the number of plies or the
number of layers of rubber-coated fabric in
the tire tread and sidewall. Tire
manufacturers also must indicate the ply
materials in the tire and sidewall, which
include steel, nylon, polyester, and others.
Tire speed rating
Part of tire designation (speed symbol);
indicates the speed range for which a tire is
approved.
Total load limit
Rated cargo and luggage load plus
68 kilograms (150 lb) times the vehicle’s
designated seating capacity.
Traction
The adhesive friction of a tire on a surface on
which it moves. The amount of grip provided.
Tires and wheels241Operation164_AKB; 7; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:07:36+02:00 - Seite 241Z
Tread
The portion of a tire that comes into contact
with the road.
Treadwear indicators
Narrow bands, sometimes called “wear bars”
that show across the tread of a tire when only
1 / 16 in (1.6 mm) of tread remains.
TWR (Tongue Weight Rating)
Maximum permissible weight on trailer
tongue.
Uniform Tire Quality Grading Standards
A tire information system that provides
consumers with ratings for a tire’s traction,
temperature and treadwear. Ratings are
determined by tire manufacturers using U.S.
government testing procedures. The ratings
are molded into the sidewall of the tire.
Vehicle maximum load on the tire
Load on an individual tire that is determined
by distributing to each axle its share of the
maximum loaded vehicle weight and dividing
it by two.
Winter driving
General information
Have your vehicle winterized at an authorized
Mercedes-Benz Center.
i Vehicles with diesel engine:
Do not cover the radiator, for example with
a winter front. Otherwise the readings of
the on-board diagnostic system may be
inaccurate. Some of theses readings are
required by law and must be accurate at all
times.
Winter tiresGWarning!
Winter tires with a tread depth of less than
1 / 6 in (4 mm) must be replaced. They are no
longer suitable for winter operation.
GWarning!
If you use your spare wheel 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 wheel replaced by a regular
road wheel with a winter tire at the nearest
authorized Mercedes-Benz Center.
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 352).
Always observe the speed rating of the winter
tires installed on your vehicle.
242Winter drivingOperation
164_AKB; 7; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:07:36+02:00 - Seite 242