278 OperationDriving instructionsFor information on how to identify the tire
speed rating on a tire’s sidewall, see “Tire
size designation, load and speed rating”
(page 314).
If 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
affect 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
after driving is resumed.
i
For information on speed rating for winter
tires, see “Winter driving” (
page 327).
For additional general information on tire speed
markings on tire sidewall, see “Tire speed rating”
(
page 316).
i
For more information on driving with snow
chains, see “Snow chains” (
page 328).
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.
293 Operation
Tires and wheels
Tires and wheels
See 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 re-
quired.
Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths of less than
1/8in (3 mm).
The wheels on the front and rear axles
are different. For this reason, pay at-
tention to the markings on the inside of
the wheel rims. Wheels marked “REAR
AXLE ONLY” on the inside of the rim
may only be fitted on the rear axle.
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.
315 Operation
Tires and wheels
Tire code
The tire code3 (
page 314) indicates
the tire construction type. The “R” stands
for radial tire type. Letter “D” means diag-
onal 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 316).
Rim diameter
The rim diameter4 (
page 314) 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 314) 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 319) 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 317).
Warning!
G
The tire load rating must always be at least
half of the GAWR (
page 323) 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 total load limit 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.i
Tire load rating5 (
page 314) and Tire
speed rating6 (
page 314) are also referred
to as “service description”.
318 OperationTires and wheelsDOT, 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”.1DOT
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 318)
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 318) 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 293).
Tire size
The code3 (page 318) indicates the
tire size.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
319 Operation
Tires and wheels
Tire type code
The code4 (
page 318) 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 318)
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.
Maximum tire load
1Maximum tire load rating
The maximum tire load is the maximum
weight the tires are designed to support.For more information on tire load rating
(
page 315).
For information on calculating total and
cargo load capacities (
page 297).
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
Warning!
G
Do not overload the tires by exceeding the
specified total load limit 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.
322 OperationTires and wheelsTemperature
The temperature grades are A (the high-
est), B, and C, representing the tire’s resis-
tance 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 tem-
perature 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.
Tire 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.
Warning!
G
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underin-
flation, or excessive loading, either sepa-
rately or in combination, can cause
excessive heat build-up and possible tire
failure.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
325 Operation
Tires and wheels
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 kilo-
grams (150 lbs) times the vehicle’s desig-
nated 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.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
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.
390 Practical hintsWhat to do if …Display symbol
Display messages
Possible cause/consequence
Possible solution
@
STOP, car too low
The Airmatic* is malfunctioning.
Avoid excessive steering input. The fender
or tires could otherwise be damaged. Lis-
ten for scraping noises.
Do not drive faster than 50 mph
(80 km/h).
Drive to the side of the road and select
a higher vehicle level (
page 232).
Depending on the type of malfunction,
this may raise the vehicle’s level.
Contact an authorized Mercedes-Benz
Center as soon as possible.
There is otherwise danger of an accident.
Malfunction
The system display or the system is mal-
functioning.
The system is functional only to a limited
extent.
Do not drive faster than 50 mph
(80 km/h).
Have the vehicle checked at an
authorized Mercedes-Benz Center.