352 OperationTires and wheelsWarning!
G
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust tire inflation pressure according to
the placard on the driver’s door B-pillar or, if
available, the supplemental tire pressure in-
formation on the inside of the fuel filler flap.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of pressure (e.g.
tire blowout caused by a foreign object). In
this case bring the vehicle to a halt by care-
fully applying the brakes and avoiding
abrupt steering maneuvers.
Warning!
G
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
vehicle placard or the tire inflation pressure
label. (If your vehicle has tires of a different
size than the size indicated on the vehicle
placard or the tire inflation pressure label,
you should consult the appropriate section
of this owner’s manual to determine the
proper tire inflation pressure). When the low
tire pressure telltale is illuminated, one or
more of your tires is significantly under-in-
flated. You should stop and check your tires
as soon as possible, and inflate them to the
proper pressure. Driving on a significantly
under-inflated tire causes the tire to over-
heat and can lead to tire failure. Under-infla-
tion also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s han-
dling and stopping ability.
Your vehicle has also been equipped with a
TPMS malfunction telltale to indicate when
the system is not operating properly. When
the malfunction telltale is illuminated, the
system may not be able to detect or signal
low tire pressure as intended. TPMS mal-
functions may occur for a variety of reasons,
including the installation of incompatible
replacement tires on the vehicle. Always
check the TPMS malfunction telltale after
replacing one or more tires on your vehicle
to ensure that the replacement tires are
compatible with the TPMS.
355 Operation
Tires and wheels
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:1Uniform Quality Grading Standards
(
page 362)
2DOT, Tire Identification Number (TIN)
(page 360)
3Maximum tire load (
page 361)
4Maximum tire inflation pressure
(
page 362)
5Manufacturer
6Tire ply material (
page 364)
7Tire size designation, load and speed
rating (
page 355)
8Load identification (
page 359)
9Tire nameTire size designation, load and speed
rating
1Tire width
2Aspect ratio in %
3Radial tire code
4Rim diameter
5Tire load rating
6Tire speed rating
iFor illustration purposes only. Actual
data on tires are specific to each vehi-
cle and may vary from data shown in
above illustration.
For more information, see “Rims and
tires” (
page 487).
iFor illustration purposes only. Actual
data on tires are specific to each vehi-
cle and may vary from data shown in
above illustration.
356 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 355) indicates
the nominal tire width in mm.
Aspect ratio
The aspect ratio2 (page 355) 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 355) 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 357).Rim diameter
The rim diameter4 (
page 355) 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 355) 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 361) where the maximum load as-
sociated with the load index is indicated in
kilograms and lbs.
358 OperationTires and wheelsSummer 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 is comprised of the tire load rating5
(
page 355) and the tire speed
rating6 (
page 355).
If your tire includes “ZR” in the size
designation and no service
description5 and6 (
page 355) is
given, the tire manufacturer must be
consulted for the maximum speed ca-
pability.
If a service description5 and6
(
page 355) is given, the speed capa-
bility 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 capabil-
ity of the tire is limited to 186 mph
(300 km/h).
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 rating in paren-
thesis 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
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)
Index
Speed rating
QM+S
1
1or M+S.for winter tires
up to 100 mph (160 km/h)
TM+S
1
up to 118 mph (190 km/h)
HM+S
1
up to 130 mph (210 km/h)
VM+S
1
up to 149 mph (240 km/h)
360 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 360)
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 360) 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 335).
Tire size
The code3 (page 360) indicates the
tire size.
iFor illustration purposes only. Actual
data on tires are specific to each vehi-
cle and may vary from data shown in
above illustration.
367 Operation
Tires and wheels
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.
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
1/16
in (1.6 mm) of tread
remains.
TWR (T
ongue W
eight R
ating)
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
government testing procedures. The
ratings are molded into the sidewall of the
tire.
Vehicle capacity weight
Rated cargo and luggage load plus
68 kilograms (150 lbs) times the vehicle’s
designated seating capacity.
368 OperationTires and wheelsVehicle 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.Rotating tires
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 a
front-to-rear rotation pattern that will
maintain the intended rotation (spinning)
direction of the tire (
page 338).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 configu-
ration, tires can be rotated according to
the tire manufacturer’s recommended in-
tervals 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 neces-
sary, according to the degree of tire wear.
The same rotation (spinning) direction
must be maintained (
page 338).
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 the
“Practical hints” section (
page 430) and
(
page 456).
Warning!
G
Rotate front and rear wheels only if they 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.
Warning!
G
Have the tightening torque checked after
changing a wheel. Wheels could become
loose if not tightened with a torque of
110 lb-ft (150 Nm).
Only use genuine Mercedes-Benz wheel
bolts specified for your vehicle’s rims.
457 Practical hints
Flat tire
Mounting the spare wheel
Preparing the vehicle
Prepare the vehicle as described
(page 456).
Take the wheel wrench, the collapsible
wheel chock, and the vehicle jack out
of the cargo compartment
(page 430).
Take the Minispare wheel out of the
cargo compartment (
page 433).Lifting the vehicle
Prevent the vehicle from rolling away
by blocking wheels with wheel chocks
or other sizable objects.
A collapsible wheel chock is included
with the vehicle tool kit (
page 430).
For information on setting up the col-
lapsible wheel chock, see
(
page 432).
When changing wheel on a level surface:
Place one wheel chock in front of and
another sizeable object behind the
wheel that is diagonally opposite to the
wheel being changed.
Always try lifting the vehicle using the jack
on a level surface. However, should
circumstances require you to do so on a
hill, place the wheel chock and other size-
able object as follows:
Place the wheel chock and another
sizable object on the downhill side
blocking both wheels of the axle not
being worked on.
!Vehicles with factory-mounted
running-boards*:
Your vehicle is equipped with a scis-
sors-type jack (located under the cargo
compartment floor) designed for use
with factory-mounted running boards.
Only use this jack when jacking up ve-
hicles with factory-mounted running
boards as otherwise the vehicle’s
underbody can be damaged. See sepa-
rate instructions for scissors-type jack.
Warning!
G
The jack is designed exclusively for jacking
up the vehicle at the jack take-up brackets
built into both sides of the vehicle. To help
avoid personal injury, use the jack only to lift
the vehicle during a wheel change. Never
get beneath the vehicle while it is supported
by the jack. Keep hands and feet away from
the area under the lifted vehicle. Always
firmly set parking brake and block wheels
before raising vehicle with jack.
Do not disengage parking brake while the
vehicle is raised. Be certain that the jack is
always vertical (plumb line) when in use, es-
pecially on hills. Always try to use the jack
on level surface. Make sure that the jack
arm is fully seated in the jack take-up brack-
et. Always lower the vehicle onto sufficient
capacity jackstands before working under
the vehicle.