281 Operation
Tires and wheels
Tire ply material
1Plies in sidewall
2Plies under tread
This marking tells you about the type of
cord and number of plies in the sidewall
and under the tread.
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, radio, and heater, to the extent that
these items are available as
factory-installed equipment (whether
installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire.
Air pressure is expressed in pounds per
square inch (psi), or kilopascal (kPa) or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.Bar
Another metric unit for air pressure. There
are 14.5038 pounds per square inch (psi)
to 1 bar; there are 100 kilopascals (kPa)
to 1 bar.
Bead
The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the
rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle
has been sitting for at least three hours or
driven no more than one mile (1.6 km).
Curb weight
The weight of a motor vehicle with stan-
dard equipment including the maximum
capacity of fuel, oil, and coolant, and, if so
equipped, air conditioning and additional
optional equipment, but without passen-
gers and cargo.
iFor illustration purposes only. Actual
data on tires are specific to each vehi-
cle and may vary from data shown in
above illustration.
282 OperationTires and wheelsDOT (D
epartment o
f T
ransportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross A
xle W
eight R
ating)
The GAWR is the maximum permissible
axle weight. The gross vehicle weight on
each axle must never exceed the GAWR for
the front and rear axle indicated on the
Certification label located on the driver’s
door A-pillar.
GVW (G
ross V
ehicle W
eight)
The GVW comprises the weight of the
vehicle including fuel, tools, spare wheel,
installed accessories, passengers and
cargo and, if applicable, trailer tongue
load. The GWV must never exceed the
GWVR indicated on the Certification label
located on the driver’s door A-pillar.GVWR (G
ross V
ehicle W
eight R
ating)
This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the vehicle including all options, passen-
gers, fuel, and cargo and, if applicable,
trailer tongue load). It is indicated on
Certification label located on the driver’s
door A-pillar.
Kilopascal (kPa)
The metric unit for air pressure. There are
6.9 kPa to 1 psi; another metric unit for air
pressure is bars. There are
100 kilopascals (kPa) to 1 bar.
Maximum load rating
The maximum load in kilograms and
pounds that can be carried by the tire.
Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
vehicle capacity weight and production
options weight.Maximum tire inflation pressure
This number is the greatest amount of air
pressure that should ever be put in the tire
under normal driving conditions.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by
68 kilograms (150 lbs).
Occupant distribution
The distribution of occupants in a vehicle
at their designated seating positions.
Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.
285 Operation
Tires and wheels
Thoroughly clean the mounting face of
wheels and brake disks, i.e. the inner side
of the wheels/tires, during each rotation.
Check for and ensure proper tire inflation
pressure.
For information on wheel change, see the
“Practical hints” section (
page 351).
Anti-theft wheel nuts
Your vehicle is equipped with anti-theft
wheel nuts that prevent the theft of your
vehicle’s wheels.
1Anti-theft wheel nut
2Wheel nut key
Warning!
G
Have the tightening torque checked after
changing a wheel. Wheels could become
loose if not tightened with a torque of
95 lb-ft (130 Nm).
Only use Genuine Mercedes-Benz wheel
bolts specified for your vehicle’s rims.
Warning!
G
Pull the parking brake lever up as many
notches as possible and move the gear se-
lector lever to positionP, before loosening
the wheel bolts. Otherwise the vehicle may
move and cause an accident and/or serious
personal injury. !Do not use air tools, such as an impact
wrench, when installing or removing
the anti-theft wheel nuts. An impact
wrench can damage the anti-theft
wheel nuts and the wheel nut key, or
cause them to malfunction.
!Store wheel bolts and anti-theft wheel
nuts not currently in use in a safe place
to avoid damage to the threads.
292 OperationVehicle careCleaning and care of the vehicle
If you have any questions about proper
care of your SLR, please contact an autho-
rized Mercedes-Benz Center.Depending on body color the characteris-
tic carbon structure of the body surface
may become visible due to high ambient
temperatures and humidity. This phenom-
enon is related to the technology and con-
cept of the vehicle’s body.
While in operation, even while parked, your
vehicle is subjected to varying external
influences which, if gone unchecked, can
attack the paintwork as well as the under-
body and cause lasting damage.
Such damage is caused not only by
extreme and varying climatic conditions,
but also by:
Air pollution
Road salt
Tar
Gravel and stone chipping
To avoid paint damage, you should
immediately remove:
Grease and oil
Fuel
Coolant
Brake fluid
Bird droppings
Insects
Tree resins, etc.
Frequent washing reduces and/or elimi-
nates the aggressiveness and potency of
the above adverse influences.
More frequent washings are necessary to
deal with unfavorable conditions:
near the ocean
in industrial areas (smoke, exhaust
emissions)
during winter operation
You should check your vehicle from time to
time for stone chipping or other damage.
Any damage should be repaired as soon as
possible to prevent corrosion.
Warning!
G
Many cleaning products can be hazardous.
Some are poisonous, others are flammable.
Always follow the instructions on the partic-
ular container. Always open your vehicle’s
doors or windows when cleaning the inside.
Never use fluids or solvents that are not
designed for cleaning your vehicle.iMercedes-Benz recommends that you
use Mercedes-Benz care products.
These have been specially developed
to suit Mercedes-Benz vehicles and are
state of the art. Mercedes-Benz care
products are available from any
Mercedes-Benz Center.
299 Practical hints
What to do if ...
Problem
Possible cause/consequence
Suggested solutions
-
The yellow ABS indicator
lamp comes on while driving.
The ABS has detected a malfunction and
has switched off. The BAS and the ESP
®
are also switched off (see messages in dis-
play).
The electrohydraulic brake system is still
functioning normally but without ABS
available.
If the ABS control unit is malfunctioning
the automatic transmission may also be
malfunctioning.
Continue driving with added caution. Wheels
may lock during hard braking, reducing
steering capability.
Read and observe messages in the multi-
function display (
page 307).
Have the system checked at an authorized
Mercedes-Benz Center immediately.
Failure to follow these instructions increases
the risk of an accident.
The charging voltage has fallen below
10 volts and the ABS was switched off.
When the voltage is above this value again, the
ABS is operational again.
If necessary, have the generator and battery
checked.
300 Practical hintsWhat to do if ...Problem
Possible cause/consequence
Suggested solutions
3
(Canada only)
;
(USA only)
The red brake warning lamp
comes on while driving and
you hear a warning sound.
You are driving with the parking brake on.
Release the parking brake (
page 50).
There is a malfunction in the electrohy-
draulic brake system.
Read and observe messages in the multi-
function display (
page 307).
3
(Canada only)
;
(USA only)
The red brake warning lamp
comes on while driving.
There is insufficient brake fluid in the
reservoir.
Risk of accident! Carefully stop the vehicle in
a safe location and notify an authorized
Mercedes-Benz Center. Do not add brake
fluid! This will not solve the problem.
Warning!
G
Driving with the brake warning lamp illumi-
nated can result in an accident. Have your
brake system checked immediately if the
brake warning lamp stays on. Do not add
brake fluid before checking the brake sys-
tem.
Overfilling the brake fluid reservoir can re-
sult in spilling brake fluid on hot engine
parts and the brake fluid catching fire. You
can be seriously burned.
!If you find that the brake fluid in the
brake fluid reservoir has fallen to the
minimum mark or below, have the
brake system checked for brake pad
thickness and leaks.
301 Practical hints
What to do if ...
Problem
Possible cause/consequence
Suggested solutions
ú
(USA only)
±
(Canada only)
The yellow engine malfunc-
tion indicator lamp comes on
while driving.
There is a malfunction in:
The fuel injection system
The ignition system
The emission control system
Systems which effect emissions
Such malfunctions may result in excessive
emissions values and may switch the en-
gine to its limp-home (emergency opera-
tion) mode.
Have the vehicle checked as soon as possi-
ble by an authorized Mercedes-Benz Center.
An on-board diagnostic connector is used by
the service station to link the vehicle to the
shop diagnostics system. It allows the accu-
rate identification of system malfunctions
through the readout of diagnostic trouble
codes. It is located in the front left area of
the footwell next to the parking brake.
Your gas tank is empty.
After refuelling, start, turn off and restart the
engine three or four times in succession.
The limp-home mode is canceled. You do not
need to have your vehicle checked.
The fuel cap is not closed tightly.
Check the fuel cap.
303 Practical hints
What to do if ...
Problem
Possible cause/consequence
Suggested solutions
<
The red Airbrake warning
lamp comes on while driving
and you hear a warning
sound.
The Airbrake or the central locking system
is malfunctioning.
Notify an authorized Mercedes-Benz Center
immediately.
>
The red gearshift indicator
lamp comes on while you are
driving.
You are driving with the manual shift pro-
gram. The engine is in the overrevving
range.
Shift to the next higher gear. Otherwise the
fuel supply will be interrupted to prevent the
engine from overrevving.
A
The yellow reserve fuel warn-
ing lamp lights up while you
are driving.
The fuel level has fallen into the reserve
range.
Refuel at the nearest gas station
(page 241).
=
The engine oil temperature
indicator comes on in the
tachometer while you are
driving.
The engine oil has not yet reached its
operating temperature.
Warm up the engine and do not drive at full
power until the operating temperature has
been reached.
The symbol will go out as soon as the engine
oil has reached its operating temperature.