316 OperationDriving instructionsIf you are uncertain about the correct read-
ing of the information given on a tire’s side-
wall, any authorized Mercedes-Benz
Center will be glad to assist you.
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. Try
to keep the vehicle under control by cor-
rective steering action.Road salts and chemicals can adversely af-
fect braking efficiency. Increased pedal
force may become necessary to produce
the normal braking 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 efficien-
cy should be tested as soon as possible af-
ter driving is resumed.
i
For information on speed ratings for winter
tires, see “Winter driving” (
page 363).
For additional general information on tire speed
markings on tire sidewall, see “Tire speed rating”
(
page 360).
i
For more information on driving with snow
chains, see “Snow chains” (
page 364).
Warning!
G
On slippery road surfaces, never downshift
in order to obtain braking action. This could
result in drive wheel slip and reduced vehi-
cle control. Your vehicle’s ABS will not pre-
vent this type of control loss.
Warning!
G
Make sure not to endanger any other road
users when carrying out these braking ma-
neuvers.
332 OperationTires and wheelsSee an authorized Mercedes-Benz Center
for information on tested and recommend-
ed rims and tires for summer and winter
operation. They can also offer advice con-
cerning tire service and purchase.
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 inflation pressure loss and
damage to the tire beads.
If vehicle is heavily loaded, check tire
inflation 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 of less than
1/8 in (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 compo-
nents can be damaged
The correct operating clearance of the
wheels and the tires are no longer guar-
anteed
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 re-
sult in the bolts loosening and possibly an
accident.
Retreaded tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on re-
treads. The operating safety of the vehicle
cannot be assured when such tires are used.
350 OperationTires and wheelsGeneral:
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
The tire width1 (
page 349) indicates
the nominal tire width in mm.
Aspect ratio
The aspect ratio2 (page 349) 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
The tire code3 (
page 349) 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” (
page 351).Rim diameter
The rim diameter4 (
page 349) 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 349) 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 lb
(615 kg) the tire is designed to support.
See also “Maximum tire load”
(
page 355) where the maximum load as-
sociated with the load index is indicated in
kilograms and lb.
351 Operation
Tires and wheels
For additional information on tire load
rating, see “Load identification”
(page 353).Tire speed rating
The tire speed rating6 (
page 349)
indicates the approved maximum speed
for the tire.Summer tires
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 exam-
ple: 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
Warning!
G
The tire load rating must always be at least
half of the GAWR (
page 359) of your vehi-
cle. 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.
Warning!
G
Do not overload the tires by exceeding the
specified load limit as indicated on the plac-
ard 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.
i
Tire load rating5 (
page 349) and Tire
speed rating6 (
page 349) are also referred
to as “service description”.
Warning!
G
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 injury and possible death, for you
and for others. i
Tire load rating5 (
page 349) and Tire
speed rating6 (
page 349) are also referred
to as “service description”.
Index
Speed rating
Q
up to 100 mph (160 km/h)
R
up to 106 mph (170 km/h)
S
up to 112 mph (180 km/h)
T
up to 118 mph (190 km/h)
H
up to 130 mph (210 km/h)
V
up to 149 mph (240 km/h)
W
up to 168 mph (270 km/h)
Y
up to 186 mph (300 km/h)
(Y)
above 186 mph (300 km/h)
ZR
above 149 mph (240 km/h)
353 Operation
Tires and wheels
Load identification
1Load identificationIn addition to tire load rating, special load
identification1 may be molded into the
tire sidewall following the letter designat-
ing the tire speed rating6 (
page 349).
No specification given: absence of any text
(like in above example) indicates a
standard load (SL) tire.
XL or Extra Load: designates an extra load
(or reinforced) tire.
Light Load: designates a light load tire.
C, 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 which facili-
tates efforts by tire manufactures 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”.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
354 OperationTires and wheels1DOT
2Manufacturer’s identification mark
3Tire size
4Tire type code (at the option of the tire
manufacturer)
5Date of manufactureDOT (D
epartment o
f T
ransportation)
A tire branding symbol1 (
page 354)
which denotes the tire meets require-
ments of the U.S. Department of Transpor-
tation.
Manufacturer’s identification mark
The manufacturer’s identification mark2
(
page 354) denotes the tire
manufacturer.
New tires have a mark with two symbols.
Retreaded tires have a mark with four sym-
bols. For more information on retreaded
tires, see (
page 332).
Tire size
The code3 (page 354) indicates the
tire size.Tire type code
The code4 (
page 354) 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 manufacture5 (
page 354)
identifies the week and year of manufac-
ture.
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, “3202” represents the 32nd
week of 2002.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
358 OperationTires and wheelsTire ply material
1Plies in sidewall
2Plies under tread
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), or kilopascal (kPa) or
bar.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.Bar
Another 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 driv-
en no more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with stan-
dard equipment including the maximum
capacity of fuel, oil, and coolant, and, if so
equipped, air conditioning and additional
optional equipment, but without passen-
gers and cargo.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
360 OperationTires and wheelsPSI (P
ounds per s
quare i
nch)
A standard unit of measure for air pressure
-> bar, kilopascal (kPa).
Recommended tire inflation pressure
Recommended tire inflation pressure
listed on Tire and Loading Information
placard located on driver’s door B-pillar for
normal driving conditions. Provides best
handling, tread life and riding comfort.
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 (T
ire I
dentification N
umber)
Unique identifier which facilitates efforts
by tire manufacturers to notify purchasers
in recall situations or other safety matters
concerning tires and gives purchases the
means to easily identify such tires. The TIN
is comprised of “Manufacturer’s identifica-
tion mark”, “Tire size”, “Tire type code”
and “Date of manufacture”.
Tire load rating
Numerical code associated with the
maximum load a tire can support.
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 manufac-
turers 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; 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
Force exerted by the vehicle on the road
via the tires. The amount of grip provided.
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
1/16in (1.6 mm) of tread
remains.