2014 MERCEDES-BENZ SLK-CLASS ROADSTER wheel

Maximum load rating
Maximum load rating
:is the maximum
permissible weight for which the tire is
approved.
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 317).
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
DOT, Tire Identification Number (TIN) U.S. tire regulations prescribe that every tire
manufacturer or retreader must imprint a TIN
in or on the sidewall of every tire produced. The TIN is a unique identification number. The
TIN makes it easier for tire manufacturers or
retreaders to notify customers of recalls or
other safety-related matters. It makes it possible for the purchaser to easily identify
the affected tires.
The TIN consists of the manufacturer
identification code
;, tire size=, tire type
code ?and manufacturing date A.
DOT (Department of Transportation): tire
symbol :indicates that the tire complies
with the requirements of the U.S. Department
of Transportation.
Manufacturer identification code:
manufacturer identification code ;provides
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 306).
Tire size: identifier=describes the tire size.
Tire type code: tire type code?can be
used by the manufacturer as a code to
describe specific characteristics of the tire.
Date of manufacture: date of manufacture
A 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.
i Tire data is vehicle-specific and may
deviate from the data in the example.
Tire characteristics All about wheels and tires
325Wheels and tires Z

This information describes the type of tire
cord and the number of layers in
sidewall :and under tire tread ;.
i Tire data is vehicle-specific and may
deviate from the data in the example.
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.
14.5038 pounds 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.
Normal occupant weight
The number of occupants which the vehicle
is designed for, multiplied by 68 kilograms
(150 lb).
Uniform Tire Quality Grading Standards
A uniform standard to grade the quality of
tires with regards to tread quality, tire traction
and temperature characteristics. Ratings are
determined by tire manufacturers using U.S.
government testing procedures. The ratings
are molded into the sidewall of the tire.
Recommended tire pressure
The recommended tire pressure applies to
the tires mounted at the factory.
The Tire and Loading Information placard
contains the recommended tire pressures for
cold tires on a fully loaded vehicle and for the
maximum permissible vehicle speed.
The tire pressure table contains the
recommended pressures for cold tires for various operating conditions, i.e. differing
load and speed conditions.
Increased vehicle weight due to optional
equipment
This is the combined weight of all standard
and optional equipment available for the
vehicle, regardless of whether it is actually
installed on the vehicle or not.
Rim
This is the part of the wheel on which the tire
is mounted.
GAWR (Gross Axle Weight Rating)
The GAWR is the maximum permissible axle
weight. The actual load on an axle must never
exceed the gross axle weight rating. The
gross axle weight rating can be found on the
vehicle identification plate on the B-pillar on
the driver's side.
Speed rating
The speed rating is part of the tire
identification. It specifies the speed range for
which the tire is approved.
GVW (Gross Vehicle Weight)
The gross vehicle weight includes the weight
of the vehicle including fuel, tools, the spare
wheel, accessories installed, occupants,
luggage and the drawbar noseweight, if
applicable. The gross vehicle weight must not
exceed the gross vehicle weight rating GVWR
as specified on the vehicle identification plate
on the B pillar on the driver's side.
GVWR (Gross Vehicle Weight Rating)
The GVWR is the maximum permissible gross
weight of a fully loaded vehicle (the weight of
the vehicle including all accessories,
occupants, fuel, luggage and the drawbar
noseweight, if applicable). The gross vehicle
weight rating is specified on the vehicle
identification plate on the B-pillar on the
driver's side. 326
All about wheels and tiresWheels and tires

Maximum loaded vehicle weight
The maximum weight is the sum of:
R
the curb weight of the vehicle
R the weight of the accessories
R the load limit
R the weight of the factory installed optional
equipment
Kilopascal (kPa)
Metric unit for tire pressure. 6.9 kPa
corresponds to 1 psi. Another unit for tire
pressure is bar. There are 100 kilopascals
(kPa) to 1 bar.
Load index
In addition to the load-bearing index, the load
index may also be imprinted on the sidewall
of the tire. This specifies the load-bearing
capacity more precisely.
Curb weight
The weight of a vehicle with standard
equipment including the maximum capacity
of fuel, oil and coolant. It also includes the air-
conditioning system and optional equipment
if these are installed in the vehicle, but does
not include passengers or luggage.
Maximum load rating
The maximum tire load is the maximum
permissible weight in kilograms or lbs for
which a tire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for one
tire.
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.
Cold tire pressure
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 been driven for less 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 kilograms (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 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 All about wheels and tires
327Wheels and tires Z

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.
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 áin
(1.6 mm) has been reached.
Occupant distribution
The distribution of occupants in a vehicle at
their designated seating positions.
Total load limit
Rated cargo and luggage load plus
68 kilograms (150 lb) multiplied by the
number of seats in the vehicle. Changing a wheel
Flat tire
You can find information on what to do in the
event of a flat tire in the "Breakdown
assistance" section (Y page 289).
Information on driving with MOExtended tires
in the event of a flat tire can be found under
"MOExtended tires (tires with run-flat
characteristics" (Y page 290).
The "Breakdown assistance" section
(Y page 289) contains information and notes
on how to deal with a flat tire. Information on
driving with MOExtended tires in the event of
a flat tire can be found under "MOExtended
tires (tires with run-flat characteristics"
(Y page 290). Rotating the wheels
G
WARNING
Interchanging the front and rear wheels may
severely impair the driving characteristics 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.
! On vehicles equipped with a tire pressure
monitor, electronic components are
located in the wheel.
Tire-mounting tools should not be used
near the valve. This could damage the
electronic components.
Only have tires changed at a qualified
specialist workshop.
Always pay attention to the instructions and
safety notes when changing a wheel
(Y page 329).
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 no
warranty book is available, the tires should be
rotated every 3,000 to 6,000 mile s (5,000 to
10,000 km), or earlier if tire wear requires. Do
not change the direction of wheel rotation.
Clean the contact surfaces of the wheel and
the brake disc thoroughly every time a wheel
is rotated. Check the tire pressure and, if
necessary, restart the tire pressure loss
warning system or the tire pressure monitor. 328
Changing a wheelWheels and tires

Direction of rotation
Tires with a specified direction of rotation
have additional benefits, e.g. if there is a risk
of hydroplaning. You will only gain these
benefits if the correct direction of rotation is
maintained.
An arrow on the sidewall of the tire indicates
its correct direction of rotation. Storing wheels
Store wheels that are not being used in a cool,
dry and preferably dark place. Protect the
tires from oil, grease, gasoline and diesel. Cleaning the wheels
G
WARNING
The water jet from a circular jet nozzle (dirt
blasters) can cause invisible exterior damage
to the tires or chassis components.
Components damaged in this way may fail
unexpectedly. There is a risk of an accident.
Do not use power washers with circular jet
nozzles to clean the vehicle. Have damaged
tires or chassis components replaced
immediately. Mounting a wheel
Preparing the vehicle X
Stop the vehicle on solid, non-slippery and
level ground.
X Apply the electric parking brake manually.
X Bring the front wheels into the straight-
ahead position.
X Vehicles with manual transmission:
fully depress the clutch pedal and engage
first or reverse gear.
X Vehicles with automatic transmission:
move the selector lever to P.
X Switch off the engine. X
Vehicles without KEYLESS-GO: remove
the SmartKey from the ignition lock.
X Vehicles with KEYLESS-GO: open the
driver's door.
The on-board electronics now have status
0. This is the same as the SmartKey having
been removed.
X Vehicles with KEYLESS-GO: remove the
Start/Stop button from the ignition lock
(Y page 139).
X If included in the vehicle equipment,
remove the tire-change tool kit from the
vehicle.
X Secure the vehicle to prevent it from rolling
away.
i Due to differences in vehicle equipment,
not all vehicles are equipped with a tire-
change tool kit. For information on which
tools are required to perform a wheel
change on your vehicle, consult an
authorized Mercedes-Benz Center.
Necessary wheel-changing tools can
include, for example:
R Jack
R Wheel chock
R Lug wrench
Securing the vehicle to prevent it from
rolling away If your vehicle is equipped with a wheel chock,
it can be found in the tire-change tool kit
(Y
page 289).
The folding wheel chock is an additional
securing measure to prevent the vehicle from Changing a wheel
329Wheels andtires Z

rolling away, for example when changing a
wheel.
X Fold both plates upwards :.
X Fold out lower plate ;.
X Guide the lugs on the lower plate fully into
the openings in base plate =.Securing the vehicle on level ground
X
On level ground: place chocks or other
suitable items under the front and rear of
the wheel that is diagonally opposite the
wheel you wish to change. 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
jacking point of the vehicle. The base of the
jack must be positioned vertically, directly
under the jacking point of the vehicle.
! The jack is designed exclusively for
jacking up the vehicle at the jacking points.
Otherwise, your vehicle could be damaged.
The following must be observed when raising
the vehicle:
R to raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If used
incorrectly, the jack could tip over with the
vehicle 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
performing maintenance work under the
vehicle.
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. Never
disengage 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, 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 never lie under the raised vehicle.
R never start the engine when the vehicle is
raised. 330
Changing a wheelWheels and tires

R
never open or close a door or the trunk lid
when the vehicle is raised.
R make sure that no persons are present in
the vehicle when the vehicle is raised. X
Using lug wrench :, loosen the bolts on
the wheel you wish to change by about one
full turn. Do not unscrew the bolts
completely. The jacking points are located just behind the
front wheel housings and just in front of the
rear wheel housings (arrows). Covers, front (example: vehicles with AMG
equipment) AMG vehicles and vehicles with AMG
equipment:
to protect the vehicle body, the
vehicle has covers next to the jacking points
on the outer sills.
X AMG vehicles and vehicles with AMG
equipment: fold cover;upwards. X
Position jack ?at jacking point =. Example
X
Make sure the foot of the jack is directly
beneath the jacking point.
X Turn crank Aclockwise until jack ?sits
completely on jacking point =and the
base of the jack lies evenly on the ground.
X Turn crank Auntil the tire is raised a
maximum of 1.2 in (3 cm) off the ground.
Removing a wheel !
Do not place wheel bolts in sand or on a
dirty surface. The bolt and wheel hub
threads could otherwise be damaged when
you screw them in. Changing a wheel
331Wheels and tires Z

X
Unscrew the uppermost wheel bolt
completely.
X Screw alignment bolt :into the thread
instead of the wheel bolt.
X Unscrew the remaining wheel bolts fully.
X Remove the wheel.
Mounting a new wheel G
WARNING
Oiled or greased wheel bolts or damaged
wheel bolts/hub threads can cause the wheel
bolts to come loose. As a result, you could
lose a wheel while driving. There is a risk of
accident.
Never oil or grease wheel bolts. In the event
of damage to the threads, contact a qualified
specialist workshop immediately. Have the
damaged wheel bolts or hub threads
replaced/renewed. Do not continue driving. G
WARNING
If you tighten the wheel bolts or wheel nuts
when the vehicle is raised, the jack could tip
over. There is a risk of injury.
Only tighten the wheel bolts or wheel nuts
when the vehicle is on the ground.
Always pay attention to the instructions and
safety notes in the "Changing a wheel"
section (Y page 328).
Only use wheel bolts that have been designed
for the wheel and the vehicle. For safety
reasons, Mercedes-Benz recommends that
you only use wheel bolts which have been approved for Mercedes-Benz vehicles and the
respective wheel.
!
To prevent damage to the paintwork, hold
the wheel securely against the wheel hub
while screwing in the first wheel bolt. X
Clean the wheel and wheel hub contact
surfaces.
X Slide the wheel to be mounted onto the
alignment bolt and push it on.
X Tighten the wheel bolts until they are
finger-tight.
X Unscrew the alignment bolt.
X Tighten the last wheel bolt until it is finger-
tight.
X Vehicles with a collapsible spare
wheel: inflate the collapsible spare wheel
(Y page 338). Only then lower the vehicle.
Lowering the vehicle G
WARNING
The wheels could work loose if the wheel nuts
and bolts are not tightened to the specified
tightening torque. There is a risk of accident.
Have the tightening torque immediately
checked at a qualified specialist workshop
after a wheel is changed. 332
Changing a wheelWheels and tires