
Tire size designation, load-bearing
capacity and speed rating 0043
Tire width
0044 Nominal aspect ratio in %
0087 Tire code
0085 Rim diameter
0083 Load bearing index
0084 Speed rating
i Tire data is vehicle-specific and may devi-
ate from the data in the example.
General: depending on the manufacturer's
standards, the size imprinted in the tire wall
may not contain any letters or may contain
one letter that precedes the size description.
If there is no letter preceding the size descrip-
tion (as shown above): these are passenger
vehicle tires according to European manufac-
turing standards.
If "P" precedes the size description: these are passenger vehicle tires according to U.S.
manufacturing standards.
If "LT" precedes the size description: these
are light truck tires according to U.S. manu-
facturing standards.
If "T" precedes the size description: these are
compact emergency spare wheels at high tire pressure, to be used only temporarily in an
emergency.
Tire width: tire width0043shows the nominal
tire width in millimeters.
Height-width ratio: aspect ratio0044is the
size ratio between the tire height and tire
width and is shown in percent. The aspect ratio is calculated by dividing the tire width by
the tire height.
Tire code: tire code0087specifies the tire type.
"R" represents radial tires; "D" represents
diagonal tires; "B" represents diagonal radial
tires.
Optionally, tires with a maximum speed of
over 149 mph (240 km/h) may have "ZR" in
the size description, depending on the man-
ufacturer (e.g. 245/40 ZR 18).
Rim diameter: rim diameter0085is the diam-
eter of the bead seat, not the diameter of the
rim flange. The rim diameter is specified in
inches (in).
Load-bearing index: load-bearing index0083
is a numerical code that specifies the maxi-
mum load-bearing capacity of a tire.
Do not overload the tires by exceeding the
specified load limit. The maximum permissi-
ble load can be found on the vehicle's Tire and Loading Information placard on the B-pillar on
the driver's side (Y page 342).
Example:
Load-bearing index 91 indicates a maximum
load of 1,356 lb (615 kg) that the tires can
bear. For further information on the maximum
tire load in kilograms and lbs, see
(Y page 346).
For further information on the load bearing
index, see "Load index" (Y page 351).
Speed rating: speed rating0084specifies the
approved maximum speed of the tire. G
WARNING
Exceeding the stated tire load-bearing capa-
city and the approved maximum speed could
lead to tire damage or the tire bursting. There is a risk of accident.
Therefore, only use tire types and sizes
approved for your vehicle model. Observe the
tire load rating and speed rating required for
your vehicle.
Regardless of the speed rating, always
observe the speed limits. Drive carefully and Tire labeling
349Wheels and tires Z

Load index
i
Tire data is vehicle-specific and may devi-
ate from the data in the example.
In addition to the load-bearing index, load
index 0043may be imprinted after the letters
that identify speed rating 0084(Ypage 349) on
the sidewall of the tire.
R If no specification is given: no text (as in the
example above), represents a standard
load (SL) tire
R XL or Extra Load: represents a reinforced
tire
R Light Load: represents a light load tire
R C, D, E: represents a load range that
depends on the maximum load that the tire
can carry at a certain pressure DOT, Tire Identification Number (TIN)
U.S. tire regulations prescribe that every
manufacturer of new tires or retreader has to imprint a TIN in or on the sidewall of each tire
produced. The TIN is a unique identification number. The
TIN enables tire manufacturers to inform pur-
chasers of recalls and other safety-relevant
matters. It makes it possible for the pur-
chaser to easily identify the affected tires.
The TIN is made up of manufacturer identifi-
cation code 0044, tire size0087, tire type code 0085
and manufacturing date 0083.
i Tire data is vehicle-specific and may devi-
ate from the data in the example.
DOT (Department of Transportation): tire
symbol 0043indicates that the tire complies
with the requirements of the U.S. Department
of Transportation.
Manufacturer identification code: manu-
facturer identification code 0044provides
details on the tire manufacturer. New tires
have a code with two symbols. Retreaded
tires have a code with four symbols.
For further information about retreaded tires,
see (Y page 332).
Tire size: identifier0087describes the tire size.
Tire type code: tire type code0085can be used
by the manufacturer as a code to describe
specific characteristics of the tire.
Date of manufacture: date of manufacture
0083 provides information about the age of a
tire. The first and second positions represent the week of manufacture, starting with "01"
for the first calendar week. Positions three
and four represent the year of manufacture.
For example, a tire that is marked with
"3208", was manufactured in week 32 in
2008. Tire labeling
351Wheels and tires Z

Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the maximum axle load of one axle by two. PSI (pounds per square inch)
A standard unit of measure for tire pressure. Aspect ratio
Relationship between tire height and tire
width in percent. Tire pressure
This is pressure inside the tire applying an
outward force to each square inch of the tire's surface. The tire pressure is specified in
pounds per square inch (psi), in kilopascal
(kPa) or in bar. The tire pressure should only
be corrected when the tires are cold. Tire pressure of cold tires
The tires are cold:
R if the vehicle has been parked without
direct sunlight on the tires for at least three
hours and
R if the vehicle has not been driven further
than 1 mile (1.6 km) Tread
The part of the tire that comes into contact
with the road. Bead
The tire bead ensures that the tire sits
securely on the wheel. There are several steel
wires in the bead to prevent the tire from
coming loose from the wheel rim. Sidewall
The part of the tire between the tread and the
bead. Weight of optional extras
The combined weight of those optional extras that weigh more than the replaced standard
parts and more than 2.3 kg (5 lbs). These
optional extras, such as high-performance
brakes, level control, a roof rack or a high-
performance battery, are not included in the
curb weight and the weight of the accesso-
ries. TIN (Tire Identification Number)
This is a unique identifier which can be used
by a tire manufacturer to identify tires, for
example for a product recall, and thus identify the purchasers. The TIN is made up of the
manufacturer's identity code, tire size, tire
type code and the manufacturing date. Load bearing index
The load bearing index (also load index) is a
code that contains the maximum load bearing
capacity of a tire. Traction
Traction is the result of friction between the
tires and the road surface. TWR (Tongue Weight Rating)
The TWR specifies the maximum permissible
weight that the ball coupling of the trailer tow
hitch can support. 354
Definition of terms for tires and loadingWheels and tires

Securing the vehicle on slight downhill gradients
X On light downhill gradients: place
chocks or other suitable items in front of
the wheels of the front and rear axle. Raising the vehicle
G
WARNING
If you do not position the jack correctly at the appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate jack-
ing point of the vehicle. The base of the jack
must be positioned vertically, directly under
the jacking point of the vehicle.
Observe the following when raising the vehi-
cle:
R To raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If used incor- rectly, the jack could tip over with the vehi-
cle raised.
R The jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It is not suited for per-
forming maintenance work under the vehi-
cle.
R Avoid changing the wheel on uphill and
downhill slopes.
R Before raising the vehicle, secure it from
rolling away by applying the parking brake
and inserting wheel chocks. Do not disen- gage the parking brake while the vehicle is
raised.
R The jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a
large, flat, load-bearing underlay must be
used. On a slippery surface, a non-slip
underlay must be used, e.g. rubber mats.
R Do not use wooden blocks or similar
objects as a jack underlay. Otherwise, the
jack will not be able to achieve its load-
bearing capacity due to the restricted
height.
R Make sure that the distance between the
underside of the tires and the ground does
not exceed 1.2 in (3 cm).
R Never place your hands and feet under the
raised vehicle.
R Do not lie under the vehicle.
R Do not start the engine when the vehicle is
raised.
R Never open or close a door or the tailgate
when the vehicle is raised.
R Make sure that no persons are present in
the vehicle when the vehicle is raised.
! The jack is designed exclusively for jack-
ing up the vehicle at the jacking points.
Otherwise, your vehicle could be damaged. X
Using lug wrench 0043, loosen the bolts on
the wheel you wish to change by about one full turn. Do not unscrew the bolts com-
pletely. Mounting a wheel
357Wheels and tires Z

Inflating the collapsible spare wheel
!
Inflate the collapsible spare wheel using
the tire inflation compressor before lower-
ing the vehicle. The wheel rim could other-
wise be damaged. X
Pull connector 0085and the air hose out of
the housing.
X Remove the cap from the valve on the col-
lapsible spare wheel.
X Screw union nut 0043on the air hose onto the
valve.
X Make sure on/off switch 0083of the tire
inflation compressor is set to 0.
X Insert plug 0085into the socket of the ciga-
rette lighter (Y page 284) or into a 12 V
power socket (Y page 284) in your vehicle.
X Make sure that the SmartKey is in position
1 (Y page 149) in the ignition lock.
X Press on/off switch 0083on the tire inflation
compressor to I.
The tire inflation compressor is switched
on. The tire is inflated. The tire pressure is
shown on pressure gauge 0087.
! Do not operate the tire inflation compres-
sor for longer than eight minutes at a time
without a break. It may otherwise overheat.
The tire inflation compressor can be oper-
ated again once it has cooled down.
X Inflate the tire to the specified tire pres-
sure. The specified tire pressure is printed on the
yellow label of the emergency spare wheel.
X When the specified tire pressure has been
reached, press on/off switch 0083on the
electric air pump to 0.
The tire inflation compressor is switched
off.
X Turn the SmartKey to position 0in the igni-
tion lock.
X If the tire pressure is higher than the speci-
fied pressure, press pressure release but-
ton 0044until the correct tire pressure has
been reached.
X Unscrew union nut 0043on the air hose from
the valve.
X Screw the cap onto the valve of the col-
lapsible spare wheel again.
X Stow plug 0085and the air hose in the lower
section of the blower housing.
X Stow the tire inflation compressor in the
vehicle.
Stowing a used collapsible spare wheel Take the following steps to stow a used col-
lapsible spare wheel. Otherwise, the collaps-
ible spare wheel will not fit in the spare wheel
well. Mercedes-Benz recommends that you
have this work carried out at a qualified spe-
cialist workshop.
! Only place the collapsible spare wheel in
the vehicle when it is dry. Otherwise, mois-
ture may get into the vehicle.
X Remove the valve extractor from the vehi-
cle tool kit.
X Unscrew the valve cap from the valve.
X Unscrew the valve insert from the valve and
release the air.
i Fully deflating the tires can take a few
minutes.
X Screw the valve insert back into the valve.
X Screw the valve cap back on. Emergency spare wheel
367Wheels and tires Z