2012 MERCEDES-BENZ SLK250 wheel size

represent higher levels of performance on the
laboratory test wheel than the minimum
required by law.
Tire labeling
Tire labeling overview
The following markings are on the tire in
addition to the tire name (sales designation)
and the manufacturer's name: 0002
Uniform tire Quality Grading Standard
(Ypage 313)
0003 DOT, Tire Identification Number
(Ypage 311)
0023 Maximu mtire load (Y page 307)
0022 Maximum tire pressure (Y page 300)
0020 Manufacturer
0021 Tire material (Y page 312)
0014 Tire size designation, load-bearing
capacity and speed rating (Y page 309)
0015 Load index (Y page 311)
0016 Tire name
i Tire data is vehicle-specific and may
deviate fro mthe data in the example. Tire size designation, load-bearing
capacity and speed rating
0002
Tire width
0003 Nominal aspect ratio in %
0023 Tire code
0022 Rim diameter
0020 Load bearing index
0021 Speed rating
i Tire data is vehicle-specific and may
deviate 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
description (as shown above): these are
passenger vehicle tires according to
European manufacturing 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.
manufacturing 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 width0002shows the nominal
tire width in millimeters.
Height-width ratio: aspect ratio0003is the
size ratio between the tire height and tire
width and is shown in percent.T he aspect Tire labeling
309Wheels and tires Z

ratio is calculated by dividing the tire width by
the tire height.
Tire code:
tire code0023specifies the tire type.
"R" represents radial tires; "D" represents
diagonal tires; "B" represents diagonal radial
tires.
Optionally, tires with a maximu mspeed of
over 149mph (240km/h) may have "ZR" in
the size description, depending on the
manufacturer (e.g. 245/40 ZR 18).
Rim diameter: rim diameter0022is the
diameter of the bead seat, not the diameter
of the rim flange. The rim diameter is
specified in inches (in).
Load-bearing index: load-bearing index0020
is a numerical code that specifies the
maximum load-bearing capacity of a tire.
Do not overload the tires by exceeding the
specified load limit. The maximum
permissible load can be found on the
vehicle's Tire and Loading Information
placard on the B-pillar on the driver's side
(Y page 304).
Example:
Al oad-bearing index of 91 indicates a
maximum load of 1,356lb (615kg) that can be
carried by the tires. For further information on
the maximum tire load in kilograms and
pounds, see (Y page 307).
For further information on the load-bearing
index, see Load index (Y page 311).
Speed rating: speed rating0021specifies the
approved maximum speed of the tire. G
WARNING
Exceeding the stated tire load-bearing
capacity 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 adapt your driving style to the traffic
conditions. Summer tires
Index Speed rating
Q up to 100mph (160 km/h)
R up to 106mph (170 km/h)
S up to 112mph (180 km/h)
T up to 118mph (190 km/h)
H up to 130mph (210 km/h)
V up to 149mph (240 km/h)
W up to 168mph (270 km/h)
Y up to 186mph (300 km/h)
ZR...Y up to 186mph (300 km/h)
ZR...(..Y) over 186mph (300 km/h)
ZR over 149mph (240 km/h)
R
Optionally, tires with a maximum speed of
over 149 mph (240km/h) may have "ZR" in
the size description, depending on the
manufacturer (e.g. 245/40 ZR 18).
The service specification is made up of
load-bearing index 0020and speed rating
0021.
R If the size description of you rtire includes
"ZR" and there are no service
specifications, ask the tire manufacturer in
order to find out the maximum speed.
If a service specification is available, the
maximum speed is limited according to the
speed rating in the service specification.
Example: 245/40 ZR 18 97 Y. In this
example, "97 Y" is the service specification.
The letter "Y" represents the speed rating
and the maximum speed of the tire is
limited to 186 mph (300km/h).
R The size description for all tires with
maximum speeds of over 186mph
(300km/h) must include "ZR", andthe
service specification must be given in 310
Tire labelingWheels and tires

The TIN is a unique identification number. The
TIN enables the tire manufacturers to inform
purchasers of recalls and other safety-
relevant matters. It makes it possible for the
purchaser to easily identify the affected tires.
The TIN is made up of manufacturer
identification code 0003, tire size0023, tire type
code 0022and manufacturing date 0020.
i Tire data is vehicle-specific and may
deviate from the data in the example.
DOT (Department of Transportation): tire
symbol 0002indicates that the tire complies
with the requirements of the U.S.D epartment
of Transportation.
Manufacturer identification code:
manufacturer identification code 0003provides
details on the tire manufacturer. New tires
have a code with two symbols. Retreaded
tires have a code with four symbols.
Further information about retreaded tires
(Y page 294).
Tire size: identifier0023describes the tire size.
Tire type code: tire type code0022can be
used by the manufacturer as a code to
describe specific characteristics of the tire.
Date of manufacture: date of manufacture
0020 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 characteristics
i
Tire data is vehicle-specific and may
deviate from the data in the example.
This information describes the tire cord and
the number of layers in sidewall 0002and under
the tread 0003. Definition of terms for tires and
loading
Tire ply composition and material
used
Describes the number of plies or the number
of layers of rubber-coated fabric in the tire
tread and sidewall. These are made of steel,
nylon, polyester and other materials. Bar
Metric unit for tire pressure.
14.5038p ounds per square inch (psi) and
100 kilopascals (kPa) are the equivalent of
1 bar. DOT (Department of Transportation)
DOT marked tires fulfill the requirements of
the United States Department of
Transportation. 312
Definition of terms for tires and loadingWheels and tires

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
accessories. 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 identification 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. Treadwear indicators
Narrow bars (tread wear bars) that are
distributed over the tire tread. If the tire tread
is level with the bars, the wear limit of 0008in
(1.6 mm) has been reached. Occupant distribution
The distribution of occupant sinavehicle at
their designated seating positions. Total load limit
Rated cargo and luggage load plus
68 kilograms (150 lb), multiplied by the
vehicle's designated seating capacity. Changing
awheel Flat tire
The "Breakdown assistance" section
(Y page 275) contains information and notes
on how to deal with a fla ttire. It also provides
instructions on changing a wheel or mounting
the spare wheel/emergency spare wheel. Interchanging the wheels
G
WARNING
Interchanging the front and rear wheels may
severely impair the drivin gcharacteristics if
the wheels or tires have different dimensions.
The wheel brakes or suspension components
may also be damaged. There is a risk of
accident.
Rotate front and rear wheels only if the wheels
and tires are of the same dimensions.
Always pay attention to the instructions and
safety notes in the "Changing tires and
mounting the spare wheel" section
(Y page 276).
The wear patterns on the front and rear tires
differ, depending on the operating conditions.
Rotate the wheels before a clear wear pattern
has formed on the tires. Front tires typically
wear more on the shoulders and the rear tires
in the center.
If your vehicle's tire configuration allows, you
can rotate the wheels according to the
intervals in the tire manufacturer's warranty
book in your vehicle documents. If this is not
available, the tires should then be replaced
every 3000 to 6000 miles (5000 to
10,000 km), or earlier if the tire wear requires
this. Do not change the direction of wheel
rotation.
Cleant he contact surfaces of the wheel and
the brake disc thoroughly every time a wheel
is interchanged. Check the tire pressures.
For information on changing tires and
mounting the spare wheel, see (Y page 276). Changing
awheel
315Wheels and tires Z

manufacturer in the vehicle document
wallet.
i Notes on the vehicle equipment –always
equip the vehicle with:
R tires of the same size on a given axle
(left/right)
R the same type of tires at a given time
(summer tires, winter tires, MOExtended
tires)
i On the following pages, you can find
information on approved wheel rims and
tire sizes for equipping your vehicle with
winter tires. Winter tires are not available
at the factory as standard equipmen tor
optional extras.
If you would like to equip your vehicle with
approved winter tires, you may also, in
certain circumstances, require rims of the
appropriate size. The sizes of the approved
winter tires may deviate from that of the
standard tires. This is dependent on the
model and the equipment installed at the
factory.
The tires and wheel rims, as well as further
information, can be obtained at a qualified
specialist workshop.
i Overview of abbreviations used in the
following tire tables:
R BA: both axles
R FA: front axle
R RA: rear axle
In the following table, the wheel/tire
combinations are assigned to the vehicle
models through variants, e.g. V1, V2 etc.: V1 SLK 250
V2 SLK 350
V3 SLK 55 AMG
i
Not all wheel and tire combinations are
available at the factory for all countries. Wheel and tire combinations
317Wheels and tires Z