2009 MERCEDES-BENZ SLR width

74 Safety and SecurityOccupant safety
Enhanced seat belt reminder system
When the engine is started, the seat belt
telltale< will always illuminate
for 6 seconds to remind you and your
passenger to fasten your seat belts.
If the driver’s seat belt is not fastened
when the engine is started, an additional
warning chime will also sound for a maxi-
mum of 6 seconds or until the driver’s seat
belt is fastened.
If after these 6 seconds, the driver’s or the
passenger’s seat belt (with the passenger
seat occupied) are not fastened with all
doors closed,

the seat belt telltale< remains illu-
minated for as long as either the
driver’s or passenger’s seat belt is not
fastened.


Never wear the shoulder belt under your
arm, against your neck or off your shoul-
der. In a frontal crash, your body would
move too far forward. That would in-
crease the chance of head and neck in-
juries. The belt would also apply too
much force to the ribs or abdomen,
which could severely injure internal
organs such as your liver or spleen.


Never wear belts over rigid or breakable
objects in or on your clothing, such as
eyeglasses, pens, keys, etc., as these
might cause injuries.


Position the lap belt as low as possible
on your hips and not across the abdo-
men. If the belt is positioned across your
abdomen, it could cause serious person-
al injuries in a crash.


Never use a seat belt for more than one
person at a time. Do not fasten a seat
belt around a person and another per-
son or other objects.


Seat belts should not be worn twisted.
In a crash, you wouldn’t have the full
width of the seat belt to manage impact
forces. The twisted seat belt against
your body could cause injuries.


Pregnant women should also always use
a lap-shoulder belt. The lap belt portion
should be positioned as low as possible
on the hips to avoid any possible
pressure on the abdomen.


Never place your feet on the instrument
panel, dashboard or on the seat. Always
keep both feet on the floor in front of the
seat.


When using a seat belt to secure infant
or toddler restraints or children in
booster seats, always follow the child
seat manufacturer’s instructions.


277 Operation
Tires and wheels
Tire size designation, load and speed
rating
1Tire width
2Aspect ratio in %
3Radial tire code
4Rim diameter
5Tire load rating
6Tire speed ratingGeneral:
Depending on the design standards used,
the tire size molded into the sidewall may
have no letter or a letter preceding the tire
size designation.
No letter preceding the size designation
(as illustrated above): Passenger car tire
based on European design standards.
Letter “P” preceding the size designation:
Passenger car tire based on U.S. design
standards.
Letter “LT” preceding the size designation:
Light Truck tire based on U.S. design
standards.
Letter “T” preceding the size designation:
Temporary spare tires which are high
pressure compact spares designed for
temporary emergency use only.
Tire width
The tire width1 (
page 277) indicates
the nominal tire width in mm. Aspect ratio
The aspect ratio2 (
page 277) is the
dimensional relationship between tire
section height and section width and is
expressed in percentage. The aspect ratio
is arrived at by dividing section height by
section width.
Tire code
The tire code3 (
page 277) indicates
the tire construction type. The “R” stands
for radial tire type. Letter “D” means diag-
onal or bias ply construction; letter “B”
means belted-bias ply construction.
At the tire manufacturer’s option, any tire
with a speed capability above 149 mph
(240 km/h) can include a “ZR” in the size
designation (for example: 245/40 ZR 18).
For additional information, see “Tire speed
rating” (
page 279).
i
For illustration purposes only. Actual data
on tires is specific to each vehicle and may vary
from data shown in above illustration.

284 OperationTires and wheelsUniform Tire Quality Grading Standards (U.S. vehicles)
Tire manufacturers are required to grade
tires based on three performance
factors: treadwear, traction and
temperature resistance.
1Treadwear
2Traction
3Temperature resistanceQuality grades can be found, where appli-
cable, on the tire sidewall between tread
shoulder and maximum section width. For
example:
All passenger car tires must conform to
federal safety requirements in addition to
these grades.Treadwear
The treadwear grade is a comparative rat-
ing based on the wear rate of the tire when
tested under controlled conditions on a
specified government test course. For ex-
ample, a tire graded 150 would wear one
and one-half (1
1/2) times as well on the
government course as a tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly
from the norm due to variations in driving
habits, service practices and differences in
road characteristics and climate.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
Treadwear
Traction
Temperature
200
AA
A

286 OperationTires and wheelsTire 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 1 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.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.

299 Operation
Vehicle care
Power washer
Cleaning the windows and wiper blades

Remove the SmartKey from the starter
switch.

Fold the wiper arm away from the
windshield (
page 363).
You must feel the wiper arm engage in
position.

Clean the wiper blade inserts with a
clean cloth and detergent solution.

Use a soft, clean cloth and a mild win-
dow cleaning solution on all outside
and inside glass surfaces.
An automotive glass cleaner is
recommended.
!
Make sure that the windshield wiper switch
is set to0 (
page 52). Otherwise, the rain
sensor could activate and cause the wipers to
move unintentionally. This may lead to vehicle
damage.
Due to the width of the vehicle, fold in exterior
rear view mirrors prior to running the vehicle
through an automatic car wash to prevent
damage to the mirrors.
i
After running the vehicle through an auto-
matic car wash, wipe any wax off of the wind-
shield (
page 299). This will prevent smears
and reduce wiping noise which can be caused by
residual wax on the windshield.
!
Do not use power washer to clean your
vehicle or the engine.
!
The hood must be opened (
page 250) be-
fore folding the wiper arm away from the wind-
shield. You could otherwise damage the hood
and/or the wiper arms.
!
Never open or close the hood when the wip-
er arms are folded away from the windshield.
You could otherwise damage the hood and/or
the wiper arm.
Warning!
G
For safety reasons, switch off wipers and
remove SmartKey from starter switch
before cleaning the wiper blades. Otherwise
the wiper motor could suddenly turn on and
cause injury.
!
Do not pull on the wiper blade inserts. They
could tear.
!
To clean the window interior, do not use a
dry cloth, abrasives, solvents or cleaners con-
taining solvents. Do not touch the inside of the
front, rear or door windows with hard objects
such as an ice scraper or ring. Doing so may
damage the windows.


391 Technical data
Main dimensions
Main dimensions
Mercedes-Benz SLR McLaren Roadster
Mercedes-Benz SLR McLaren Roadster 722 S
Overall vehicle length
183.3 in (4656 mm)
183.3 in (4656 mm)
Overall vehicle width
75.1 in (1908 mm)
75.1 in (1908 mm)
Overall vehicle width
(doors open - widest point)
111.7 in (2838 mm)
111.7 in (2838 mm)
Overall vehicle height
50.4 in (1281 mm)
50.0 in (1271 mm)
Overall vehicle height
(doors open - highest point)
80.5 in (2045 mm)
80.1 in (2035 mm)
Overall vehicle height
(soft top open - highest point)
63.0 in (1599 mm)
62.6 in (1589 mm)
Wheelbase
106.3 in (2700 mm)
106.3 in (2700 mm)
Track, front
64.5 in (1638 mm)
64.5 in (1638 mm)
Track, rear
61.8 in (1569 mm)
61.8 in (1569 mm)