2016 MERCEDES-BENZ SL-CLASS ROADSTER wheel size

approximatelyáin(1.6 mm )ha sbeen
re ached. If this is the case, the tire is so worn
that it must be replaced.
Selecting, mounting and replacing
tires
ROnly mount tires and wheels of the same
type and make.
Exception: it is permissible to install a dif-
ferent type or make in the event of a flat
tire. Observe the "MOExtended tires (tires
with run-flat characteristics" section
(
Ypage 551).
ROnly mount tires of the correct size onto
the wheels.
RBreak in new tires at moderate speeds for
the first 60 miles (100 km). They only reach
their full performance after this distance.
RDo not drive with tires which have too little
tread depth, as this significantly reduces
the traction on wet roads (hydroplaning).
RReplace the tires after six years at the lat-
est, regardless of wear.
MOExtended tires (tires with run-flat
properties)
With MOExtended tires (tires with run flat
characteristics), you can continue to drive
your vehicle even if there is a total loss of
pressure in one or more tires.
MOExtended tires may only be used in con-
junction with an active tire pressure monitor
and only on wheels specifically tested by
Mercedes-Benz.
Notes on driving with MOExtended tires with
a flat tire (
Ypage 551).
iVehicles equipped with MOExtended tires
are not equipped with a TIREFIT kit at the
factory. It is therefore recommended that
you additionally equip your vehicle with a
TIREFIT kit if you mount tires that do not
feature run-flat properties, e.g. winter tires. A TIREFIT kit can be obtained from a quali-
fied specialist workshop.
Winter operation
General notes
Have your vehicle winter-proofed at a quali-
fied specialist workshop at the onset of win-
ter.
Observe the notes in the "Changing a wheel"
section (
Ypage 588).
Driving with summer tires
At temperatures below 45
‡(+7 †), summer
tires lose elasticity and therefore traction and
braking power. Change the tires on your vehi-
cle to M+S tires. Using summer tires at very
cold temperatures could cause cracks to
form, thereby damaging the tires perma-
nently. Mercedes-Benz cannot accept
responsibility for this type of damage.
GWARNING
Damaged tires can cause tire inflation pres-
sure loss. As a result, you could lose control of
your vehicle. There is a risk of accident.
Check the tires regularly for signs of damage
and replace any damaged tires immediately.
M+S tires
GWARNING
M+S tires with a tire tread depth of less than
ã in (4 mm) are not suitable for use in winter
and do not provide sufficient traction. There is
a risk of an accident.
M+S tires with a tread depth of less than ãin
(4 mm) must be replaced immediately.
At temperatures below 45 ‡(+7 †), use win-
ter tires or all-season tires. Both types of tire
are identified by the M+S marking.
Only winter tires bearing the isnowflake
symbol in addition to the M+S marking pro-
570Winter operation
Wheels and tires

Follow recommended tire inflation pressures
and check the pressure of all the tires includ-
ing the spare wheel:
Rmonthly, at least
Rif the load changes
Rbefore beginning a long journey
Runder different operating conditions, e.g.
off-road driving
If necessary, correct the tire pressure.
iThe specifications on the sample Tire and
Loading Information placard and tire pres-
sure tables are examples. Tire pressure
specifications are vehicle-specific and may
deviate from the data shown here. The tire
pressure specifications that are valid for
your vehicle can be found on the Tire and
Loading Information placard and tire pres-
sure table on the vehicle.
General notes
The recommended tire pressures for the tires
mounted at the factory can be found on the
labels described here.
Further information on tire pressures can be
obtained at a qualified specialist workshop.
Tire and Loading Information placard
:Recommended tire pressures
The Tire and Loading Information placard is
on the B-pillar on the driver's side
(
Ypage 578).
The Tire and Loading Information placard con-
tains the recommended tire pressures for cold tires. The recommended tire pressures
are valid for the maximum permissible load
and up to the maximum permissible vehicle
speed.
Tire pressure table
The tire pressure table is on the inside of the
fuel filler flap. It shows the tire pressure for all tires approved for this vehicle by the factory,
see illustration (example).
The tire pressure table contains the recom-
mended pressures for cold tires for various
operating conditions, i.e. differing load and
speed conditions.
If a tire size precedes a tire pressure, the tire
pressure information following is only valid
for that tire size; see illustration (example).
The load conditions "partially laden" and "fully
laden" are defined in the table for different
numbers of occupants and amounts of lug-
gage. The actual number of seats may differ.
572Tire pressure
Wheels and tires

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
(
Ypage 582).
If the tire pressures have been set to the
lower values for lighter loads and/or lower
road speeds, the pressures should be reset to the higher values:
Rif you want to drive with an increased load
and/or
Rif you want to drive at higher road speeds
iThe tire pressures for increased loads
and/or higher road speeds, shown in the
tire pressure table, may have a negative
effect on driving comfort.
If the tire pressure is not set correctly, this
can lead to an excessive build up of heat and
a sudden loss of pressure.
For more information, contact a qualified spe-
cialist workshop.
Important notes on tire pressure
GWARNING
If the tire pressure drops repeatedly, the
wheel, valve or tire may be damaged. Tire
pressure that is too low may result in a tire
blow-out. There is a risk of an accident.
RCheck the tire for foreign objects.
RCheck whether the wheel is losing air or the valve is leaking.
If you are unable to rectify the damage, con-
tact a qualified specialist workshop.
GWARNING
If you fit unsuitable accessories onto tire
valves, the tire valves may be overloaded and
malfunction, which can cause tire pressure
loss. Due to their design, retrofitted tire pres- sure monitors keep the tire valve open. This
can also result in tire pressure loss. There is a
risk of an accident.
Only screw the standard valve cap or other
valve caps approved by Mercedes-Benz for
your vehicle onto the tire valve.
Use a suitable pressure gauge to check the
tire pressure. The outer appearance of a tire
does not permit any reliable conclusion about
the tire pressure. On vehicles equipped with
the electronic tire pressure monitor, the tire
pressure can be checked in the on-board
computer.
The tire temperature and pressure increase
when the vehicle is in motion. This is depend-
ent on the driving speed and the load.
Therefore, you should only correct tire pres-
sures when the tires are cold.
The tires are cold:
Rif the vehicle has been parked with the tires
out of direct sunlight for at least three
hours and
Rif the vehicle has not been driven further
than 1 mile (1.6 km)
The tire temperature changes depending on
the outside temperature, the vehicle speed
and the tire load. If the tire temperature
changes by 18 ‡ (10 †), the tire pressure
changes by ap proxi
mately 10 kPa (0.1 bar/
1.5 psi). Take this into account when check-
ing the pressure of warm tires. Only correct
the tire pressure if it is too low for the current
operating conditions. If you check the tire
pressure when the tires are warm, the result-
ing value will be higher than if the tires were
cold. This is normal. Do not reduce the tire
Tire pressure573
Wheels and tires
Z

Checking tire pressures manually
To determine and set the correct tire pres-
sure, proceed as follows:
XRemove the valve cap of the tire that is to
be checked.
XPress the tire pressure gauge securely onto
the valve.
XRead the tire pressure and compare it to
the recommended value on the Tire and
Loading Information placard or the tire
pressure table (
Ypage 571).
XIf the tire pressure is too low, increase the
tire pressure to the recommended value.
XIf the tire pressure is too high, release air.
To do so, press down the metal pin in the
valve, 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
General notes
If a tire pressure monitor is installed, the vehi-
cle's wheels have sensors that monitor the
tire pressures in all four tires. The tire pres-
sure monitor warns you if the pressure drops
in one or more of the tires. The tire pressure
monitor only functions if the corresponding
sensors are installed in all wheels.
Information on tire pressures is displayed in
the multifunction display. After a few minutes
of driving, the current tire pressure of each
tire is shown in the Serv.
menu of the multi-
function display.
Example :curren ttir epressur edisplay
For information on the message display, refer
to the "Checking the tire pressure electroni-
cally" section (
Ypage 577).
Important safety notes
GWARNING
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the pressure rec-
ommended 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 Infor-
mation 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 pres-
sure 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 underin-
flated 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 stop-
ping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the driv-
er's responsibility to maintain correct tire
pressure, even if unde rinf
lation 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 if 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 warning lamp will
flash for approximately a minute and then
Tire pressure575
Wheels and tires
Z

after driving a few minutesmes-
sage.
XPress the :button.
The Use Current Pressures as New
Reference Valuesmessage appears in
the multifunction display.
If you wish to confirm the restart:
XPress the abutton.
The Tire Press. Monitor Restarted
message appears in the multifunction dis-
play.
After driving for a few minutes, the system
checks whether the current tire pressures
are within the specified range. The new tire
pressures are then accepted as reference
values and monitored.
If you wish to cancel the restart:
XPress the %button.
The tire pressure values stored at the last
restart will continue to be monitored.
Radio type approval for the tire pres-
sure monitor
CountryRadio type approval number
USAFCC ID: MRXMW2433A
FCC ID: MRXGG4
FCC ID: MRXMC34MA4
CanadaIC: 2546A-MW2433A
IC: 2546A-GG4
IC: 2546A-MC34MA4
Loading the vehicle
Instruction labels for tires and loads
GWARNING
Overloaded tires can overheat, causing a
blowout. Overloaded tires can also impair the steering and driving characteristics and lead
to brake failure. There is a risk of accident.
Observe the load rating of the tires. The load
rating must be at least half of the GAWR of
your vehicle. Never overload the tires by
exceeding the maximum load.
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 numberof occupants and the maximum permis-
sible vehicle load. It also contains details
of the tire sizes and corresponding pres-
sures for tires mounted at the factory.
(2) The vehicle identification plate is on the B-pillar on the driver's side. The vehicle
identification plate informs you of the
gross vehicle weight rating. It is made up
of the vehicle weight, all vehicle occu-
pants, the fuel and the cargo. You can
also find information about the maximum
gross axle weight rating on the front and
rear axle.
The maximum gross axle weight rating is
the maximum weight that can be carried
by one axle (front or rear axle). Never
exceed the maximum load or the maxi-
mum gross axle weight rating for the
front or rear axle.
:B-pillar, driver's side
578Loading the vehicle
Wheels and tires

Example: steps 1 to 3
The following table shows examples on how
to calculate total and cargo load capacities
with varying seating configurations and num-
ber 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 your vehicle's
Tire and Loading Information placard
(
Ypage 578).
The greater the combined weight of the occu-
pants, the lower the maximum luggage load.
Step 1
Example 1Example 2
Combined
maximum
weight of
occupants
and cargo
(data from the
Tire and Load-
ing Informa-
tion placard)1500 lbs
(680 kg)1500 lbs
(680 kg)
Step 2
Example 1Example 2
Number of
people in the
vehicle (driver
and occu-
pants)12
Weight of the
occupantsOccu-
pant 1:
175 lbs
(80 kg)Occu-
pant 1:
175 lbs
(80 kg)
Occu-
pant 2:
195 lbs
(88 kg)
Gross weight
of all occu-
pants175 lbs
(80 kg)370 lbs
(168 kg)
Step 3
Example 1Example 2
Permissible
load (maxi-
mum gross
vehicle weight
rating from
the Tire and
Loading Infor-
mation plac-
ard minus the
gross weight
of all occu-
pants)1500 lbs
(680 kg) Ò
175 lbs
(80 kg) =
1325 lbs
(600 kg)1500 lbs
(680 kg) Ò
370 lbs
(168 kg) =
1130 lbs
(512 kg)
Vehicle identification plate
Even if you have calculated the total cargo
carefully, you should still make sure that the
gross vehicle weight rating and the gross axle
weight 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
(
Ypage 578).
580Loading the vehicle
Wheels and tires

The safe speed on a wet, snow covered or icy
road is always lower than on dry road surfa-
ces.
You should pay special attention to road con-
ditions when temperatures are around freez-
ing point.
Mercedes-Benz recommends a minimum
tread depth ofãin (4 mm) on all four winter
tires. Observe the legally required minimum
tire tread depth (
Ypage 569). Winter tires can
reduce the braking distance on snow-covered
surfaces in comparison with summer tires.
The braking distance is still much further than
on surfaces that are not icy or covered with
snow. Take appropriate care when driving.
Further information on winter tires (M+S
tires) (
Ypage 570).
Temperature
GWARNING
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underinfla-
tion, or excessive loading, either separately or
in combination, can cause excessive heat
build-up and possible tire failure.
The temperature grades are A (the highest), B,
and C. These represent the tire's resistance
to the generation of heat and its ability to dis-
sipate heat when tested under controlled
conditions on a specified indoor laboratory
test wheel. Sustained high temperature can
cause the material of the tire to degenerate
and reduce tire life, and excessive tempera-
ture 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
Overview
:Uniform Tire Quality Grading Standard
(
Ypage 586)
;DOT, Tire Identification Number
(
Ypage 585)
=Maximum tire load (Ypage 585)
?Maximum tire pressure (Ypage 574)
AManufacturer
BTire material (Ypage 586)
CTire size designation, load-bearing capa-
city and speed index (
Ypage 582)
DLoad index (Ypage 585)
ETire name
The markings described above are on the tire
in addition to the tire name (sales designa-
tion) and the manufacturer's name.
iTire data is vehicle-specific and may devi-
ate from the data in the example.
Tire size designation, load-bearing
capacity and speed rating
GWARNING
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.
582All about wheels and tires
Wheels and tires

Therefore, only use tire types and sizes
approved for your vehicle model. Observe the
tire load rating and speed rating required for
your vehicle.
:Tire width
;Nominal aspect ratio in %
=Tire code
?Rim diameter
ALoad bearing index
BSpeed rating
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: compactemergency wheels with high tire pressure
that are only designed for temporary use in an
emergency.
Tire width: tire width:shows the nominal
tire width in millimeters.
Height-width ratio: aspect ratio;is 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 code=specifies 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 diameter?is 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 indexA
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 (Ypage 578).
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 ma
ximum
tire load in kilograms and lbs, see
(
Ypage 585).
For further information on the load bearing
index, see "Load index" (
Ypage 585).
Speed rating: speed ratingBspecifies the
approved maximum speed of the tire.
iTire data is vehicle-specific and may devi-
ate from the data in the example.
Regardless of the speed rating, always
observe the speed limits. Drive carefully and
adapt your driving style to the traffic condi-
tions.
All about wheels and tires583
Wheels and tires
Z