2012 MERCEDES-BENZ SLS AMG ROADSTER wheel size

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops ( Y page 21).
Important safety notes
Consult an authorized Mercedes-Benz Center
if you require information on approved and
recommended tires and wheels for summer
and winter operation. Advice on purchasing
and caring for tires is also available there.
GWARNING
Replace rims or tires with the same
designation, manufacturer and type as shown
on the original part. For further information
contact an authorized Mercedes-Benz Center.
If incorrectly sized rims and tires are
mounted, the wheel brakes or suspension
components can be damaged. Also, the
operating clearance of the wheels and the
tires may no longer be correct.
GWARNING
Worn, old tires can cause accidents. If the tire
tread is worn to minimum tread depth, 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 result
in the bolts loosening and possibly an
accident.
Retreaded tires are not tested or
recommended by Mercedes-Benz, since
previous damage cannot always be
recognized on retreads. The operating safety
of the vehicle cannot be assured when such
tires are used.GWARNING
If you feel a sudden significant vibration or
ride disturbance, or you suspect that possible
damage to your vehicle has occurred, you
should turn on the hazard warning flashers,
carefully slow down, and drive with caution to
an area which is a safe distance from the road.
Inspect the tires and the vehicle underbody
for possible damage. If the vehicle appears
unsafe, have the vehicle towed to the nearest
authorized Mercedes-Benz Center or tire
dealer for repairs.
GWARNING
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
might lose control of the vehicle. Continued
driving with a flat tire or driving at high speed
with a flat tire will cause excessive heat build-
up and possibly a fire.
i Further information about tires and
wheels can be obtained from any
authorized Mercedes-Benz Center.
Operation
Notes on driving
R If the vehicle is heavily laden, check the tire
pressures and correct them if necessary.
R When parking your vehicle, make sure that
the tires do not get deformed by the curb
or other obstacles. If it is necessary to drive
over curbs, speed humps or similar
elevations, try to do so slowly and at an
obtuse angle. Otherwise, the tires,
particularly the sidewalls, can get
damaged.
250OperationTires and wheels

Notes on regularly inspecting wheels
and tiresGWARNING
Regularly check the tires for damage.
Damaged tires can cause tire inflation
pressure loss. As a result, you could lose
control of your vehicle.
Worn, old tires can cause accidents. If the tire
tread is worn to minimum tread depth, or if
the tires have sustained damage, replace
them.
R Regularly check the wheels and tires of
your vehicle for damage (e.g. cuts,
punctures, tears, bulges on tires and
deformation or cracks or severe corrosion
on wheels) at least once a month, as well
as after driving off-road or on rough roads.
Damaged wheels can cause a loss of tire
pressure.
R Regularly check the tire tread depth and
the condition of the tread across the whole
width of the tire (Y page 251). If necessary,
turn the front wheels to full lock in order to
inspect the inner side of the tire surface.
R All wheels must have a valve cap to protect
the valve against dirt and moisture. Do not
mount anything onto the valve (such as tire
pressure monitoring systems) other than
the standard valve cap or other valve caps
approved by Mercedes-Benz for your
vehicle.
R Regularly check the pressure of all the tires
including the emergency spare wheel or the
spare wheel, particularly prior to long trips,
and correct the pressure as necessary
( Y page 253).
Tire tread
GWARNING
Although the applicable federal motor vehicle
safety laws consider a tire to be worn when
the tread wear indicators (TWI) become
visible at approximately 1
/ 16 in (1.6 mm), we
recommend that you do not allow your tires
to wear down to that level. As tread depth
approaches 1
/ 8 in (3 mm), the adhesion
properties on a wet road are sharply reduced.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
Do not use tires that are excessively worn as
the tire traction on wet road surfaces
decreases significantly when the tread depth
is less than ⅛ inch (3 mm).
Tread wear indicators (TWI) are required by
law. Six indicators are positioned on the tire
tread. They become visible as soon as a tread
depth of approximately 1
/ 16 inch (1.6 mm)
has been reached. If this is the case, the tire
is so worn that it must be replaced.
The recommended tread depth for summer
tires is at least ⅛ inch (3 mm). The
recommended tread depth for winter tires is
at least 1
/ 6 inch (4 mm).
Bar marking
: for tread wear is integrated
into the tire tread.
Notes on selecting, mounting and
replacing tires
R Only mount tires and wheels of the same
type and make.
R Only mount tires of the correct size onto
the wheels.
R After mounting new tires, run them in at
moderate speeds for the first 60 miles
Operation251Tires and wheelsZ

(100 km) as they only reach their full
performance after this distance.
R Do not use tires that are excessively worn
as the tire traction on wet road surfaces
decreases significantly when the tread
depth is less than 1
/ 8 inch (3 mm).
R Replace the tires after six years at the
latest, regardless of wear. This also applies
to the spare wheel/emergency spare
wheel.
The service life of tires depends on the
following factors amongst other things:
R driving style
R tire pressure
R mileage
Winter operation
General notes
Have your vehicle winterproofed at a qualified
specialist workshop at the onset of winter.
Observe the notes in the "Changing a wheel"
section ( Y page 271).
Driving with summer tires
At temperatures below 45 ‡ (+7 †), the
elasticity of summer tires and therefore also
the traction and braking capability are
reduced considerably — equip your vehicle
with M+S tires. Using summer tires at very
cold temperatures could cause tears to form,
thereby damaging the tires permanently.
Mercedes-Benz cannot accept responsibility
for this type of damage.
Snow chains
! There is not enough space for snow
chains on some wheel sizes. Observe the
information under "Tires and wheels" in the
"Technical Data" section to avoid damage
to the vehicle or the wheels.
For safety reasons, Mercedes-Benz
recommends that you only use snow chains
that have been specially approved for your
vehicle by Mercedes-Benz, or are of a
corresponding standard of quality.
R local regulations may restrict the use of
snow chains. Observe the appropriate
regulations if you wish to mount snow
chains.
R only use snow chains when driving on roads
completely covered by snow. Remove the
snow chains as soon as possible when you
come to a road that is not snow-covered.
R Do not exceed the maximum permissible
speed of 30 mph (50 km/h).
R you may not mount snow chains to all
wheel-tire combinations; see the
information under "Wheels and tires" in the
"Technical data" section.
R snow chains must not be mounted on
emergency spare wheels.
R mount snow chains only in pairs and only
on the rear wheels. Observe the
manufacturer's installation instructions.
! If snow chains are mounted on the front
wheels, the snow chains could grind
against the bodywork or components of the
chassis. This could result in damage to the
vehicle or the tires.
i You may wish to deactivate
ESP ®
(Y page 56) when pulling away with
snow chains mounted. This way you can
allow the wheels to spin in a controlled
manner, achieving an increased driving
force (cutting action).
M+S tires
GWARNING
M+S tires with a tread depth of less than 1
/ 6
inch (4 mm) must be replaced. They are no
longer suitable for winter operation.
252Winter operationTires and wheels

Example: tire pressure table for all tires permitted
for this vehicle by the factory
If a tire size precedes a tire pressure, the tire
pressure information following is only valid
for that tire size. The load conditions "partially
laden" and "fully laden" are defined in the
table for different numbers of passengers and
amounts of luggage. The actual number of
seats may differ.
Example: tire pressure table with tire dimensions
Some tire pressure tables show only the rim
diameters instead of the full tire size, e.g.
R18 . The rim diameter is part of the tire size
and can be found on the tire sidewall
( Y page 265).
Underinflated or overinflated tires
Underinflation
GWARNING
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated.
Underinflated tires may:
R wear quickly and unevenly
R have an adverse effect on fuel consumption
R overheat, leading to tire defects
R have an adverse effect on handling
characteristics
Overinflation
GWARNING
Follow recommended tire inflation pressures.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
Overinflated tires may:
R have an adverse effect on handling
characteristics
R wear quickly and unevenly
Tire pressure255Tires and wheelsZ

using the tip of a pen, for example. Then
check the tire pressure again using the tire
pressure checker.XScrew the valve cap onto the valve.XRepeat these steps for the other tires.
Tire pressure monitor
Important safety notes
If a tire pressure monitor system is installed,
the vehicle's wheels have sensors that
monitor the tire pressures in all four tires. The
tire pressure monitor warns you if the
pressure drops in one or more of the tires. The
tire pressure monitor only functions if the
correct wheel electronics units are installed
on each wheel.
The tire pressure monitor has a yellow
warning lamp in the instrument cluster for
indicating pressure loss/malfunctions (USA)
or pressure loss (Canada). Whether the
warning lamp flashes or lights up indicates
whether a tire pressure is too low or the tire
pressure monitoring system is
malfunctioning:
R if the warning lamp is lit continuously, the
tire pressure on one or more tires is
significantly too low. The tire pressure
monitor is not malfunctioning.
R USA only: if the warning lamp flashes for
60 seconds and then remains lit constantly,
the tire pressure monitor is malfunctioning.
GWARNING
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the pressure
recommended by the vehicle manufacturer
on the Tire and Loading Information placard
on the driver's door B-pillar or the tire
pressure label on the inside of the fuel filler
flap. If your vehicle has tires of a different size
than the size indicated on the Tire and Loading
Information placard or the tire pressure label,
you should determine the proper tire pressure
for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring
system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires are significantly underinflated.
Accordingly, when the low tire pressure
telltale illuminates, you should stop and check
your tires as soon as possible, and inflate
them to the proper pressure. Driving on a
significantly underinflated tire causes the tire
to overheat and can lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle's
handling and stopping ability. Please note that
the TPMS is not a substitute for proper tire
maintenance, and it is the driver's
responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level to trigger illumination of the
TPMS low tire pressure telltale.
USA only:
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined with
the low tire pressure telltale. When the
system detects a malfunction, the telltale will
flash for approximately 1 minute and then
remain continuously illuminated. This
sequence will continue upon subsequent
vehicle start-ups as long as the malfunction
exists. When the malfunction indicator is
illuminated, the system may not be able to
detect or signal low tire pressure as intended.
TPMS malfunctions may occur for a variety of
reasons, including the installation of
incompatible replacement or alternate tires
or wheels on the vehicle that prevent the
TPMS from functioning properly. Always
check the TPMS malfunction telltale after
replacing one or more tires or wheels on your
vehicle to ensure that the replacement or
alternate tires and wheels allow the TPMS to
continue to function properly.Tire pressure257Tires and wheelsZ

Each tire that is affected by a significant loss
of pressure is highlighted with a color.
If the following message appears in the
multifunction display: Correct Tire
PressureXCheck the tire pressure on all four wheels
and correct it if necessary.
i If the wheel positions on the vehicle are
interchanged, the tire pressures may be
displayed for the wrong positions for a
short time. This is rectified after a few
minutes of driving, and the tire pressures
are displayed for the correct positions.
Restarting the tire pressure monitor
When you restart the tire pressure monitor,
all existing warning messages are deleted and
the warning lamps go out. The monitor uses
the currently set tire pressures as the
specified values for monitoring.
In most cases, the tire pressure monitor will
automatically detect the new reference
values, e.g. if you have:
R changed the tire pressure
R changed the wheels or tires
R mounted new wheels or tires
If you are defining the new reference values
manually:
XUse the table on the inside of the fuel filler
flap to ensure that the tire pressure is set
correctly in all four tires for the current
operating conditions.
Also observe the notes in the section on tire
pressures ( Y page 253).XSelect key position 2 with the Start/Stop
button.XPress the = or ; button to select the
Service menu.XPress the 9 or : button to select
TIRE PRESS. .XPress the a button.
The display shows either the current tire
pressure for the individual tires or theTire pressures will be displayed
after driving a few minutes
message.XPress the : button.
The Use Current Pressures as New
Reference Values message appears in
the multifunction display.XPress the a button.
The Tire Press. Monitor Restarted
message appears in the multifunction
display.
After a few minutes of driving, the current
pressures are adopted as the new
monitoring values.
Canceling the restart
XPress the % button.
or
XPress the 9 button to leave the menu.
Loading the vehicle
Instruction labels for tires and loads
GWARNING
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard 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.
Two instruction labels on your vehicle show
the maximum possible load.
(1)The Tire and Loading Information placard
is on the B-pillar on the driver's side. The
Tire and Loading Information placard
shows the maximum permissible number
of occupants and the maximum
permissible vehicle load. It also contains
details of the tire sizes andLoading the vehicle259Tires and wheelsZ

Example: steps 1 to 3
The following table shows examples on how to calculate total load and cargo capacities with
varying seating configurations and number and size of occupants. The following examples use
a load limit of 1500 lbs (680 kg). This is for illustration purposes only. Make sure you are
using the actual load limit for your vehicle stated on the vehicle’s Tire and Loading Information
placard ( Y page 260).
Example 1Example 2Step 1Combined maximum
weight of occupants and
cargo (data from the Tire
and Loading Information
placard)1500 lbs (680 kg)1500 lbs (680 kg)Example 1Example 2Step 2Number of people in the
vehicle (driver and
occupants)12Weight of the occupantsOccupant 1: 175 lbs
(80 kg)Occupant 1: 175 lbs
(80 kg)
Occupant 2: 195 lbs)
(88 kgGross weight of all
occupants175 lbs (80 kg)370 lbs (168 kg)Example 1Example 2Step 3Permissible cargo and
trailer load/noseweight
(maximum gross vehicle
weight rating from the Tire
and Loading Information
placard minus the gross
weight of all occupants)1500 lbs (680 kg) -
175 lbs (80 kg) =
1325 lbs (600 kg)1500 lbs (680 kg) -
370 lbs (168 kg) =
1130 lbs (512 kg)
The higher the weight of all the occupants, the smaller the maximum load for luggage.
Further information can be found under "Towing a trailer" ( Y page 263).
Vehicle identification plate
Even if you have calculated the total load
carefully, you should still make sure that the
gross vehicle weight rating and the gross axleweight rating are not exceeded. Details can
be found on the vehicle identification plate on
the B-pillar on the driver's side of the vehicle
( Y page 259).262Loading the vehicleTires and wheels

laboratory test wheel. Sustained high
temperature 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 labeling
Tire labeling overview
The following markings are on the tire in
addition to the tire name (sales designation)
and the manufacturer's name:
:Uniform Tire Quality Grading Standard
( Y page 269);DOT, Tire Identification Number
( Y page 268)=Maximum tire load ( Y page 263)?Maximum tire pressure ( Y page 256)AManufacturerBTire material ( Y page 268)CTire size designation, load-bearing
capacity and speed rating ( Y page 265)DLoad index ( Y page 267)ETire name
i
Tire data is vehicle-specific and may
deviate from the data in the example.
Tire size designation, load-bearing
capacity and speed rating
:Tire width;Nominal aspect ratio in %=Tire code?Rim diameterALoad bearing indexBSpeed 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
Tire labeling265Tires and wheelsZ