2008 MERCEDES-BENZ R320 width

84 Safety and Security
Occupant safety
Warning!G
USE SEAT BELTS PROPERLY

Seat belts can only work when used
properly. Never wear seat belts in any
other way than as described in this sec-
tion, as that could result in serious inju-
ries in case of an accident.

Each occupant should wear their seat
belt at all times, because seat belts help
reduce the likelihood of and potential
severity of injuries in accidents, includ-
ing rollovers. The integrated restraint
system includes SRS (driver air bag, pas-
senger front air bag, side impact air
bags, window curtain air bags for side
windows) and ETD (seat belt emergency
tensioning device), and front seat knee
bolsters. The system is designed to en-
hance the protection offered to properly
belted occupants in certain frontal (front
air bags and ETD) and side (side impact,
window curtain air bags and ETD) im-
pacts which exceed preset deployment
thresholds and in certain rollovers (win-
dow curtain air bags and ETD).

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 or-
gans such as your liver or spleen.

Never wear belts over rigid or breakable
objects in or on your clothing, such as
eyeglasses, pens, SmartKeys, 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 injuries
in a crash.

Never use a seat belt for more than one
p e r s o n a t t i m e . D o n o t f a s t e n a s e a t b e l t
around a person and another person or
other objects.

Belts should not be worn twisted. In a
crash, you would not have the full width
of the belt to distribute impact forces.
The twisted 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.

384 Operation
Tires and wheels
Tire labeling
Besides tire name (sales designation) and
manufacturer name, a number of markings
can be found on a tire.
Following are some explanations for the
markings on your vehicle’s tires:1Uniform Quality Grading Standards
(
page 391)
2DOT, Tire Identification Number (TIN)
(
page 388)
3Maximum tire load (
page 390)
4Maximum tire inflation pressure
(
page 390)
5Manufacturer
6Tire ply material (
page 393)
7Tire size designation, load and speed
rating (
page 384)
8Load identification (
page 388)
9Tire nameTire size designation, load and speed
rating
1Tire width
2Aspect ratio in %
3Radial tire code
4Rim diameter
5Tire load rating
6Tire speed rating
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
For more information, see “Rims and tires”
(
page 529).
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.

385 Operation
Tires and wheels
General:
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 384) indicates
the nominal tire width in mm.
Aspect ratio
The aspect ratio2 (
page 384) 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 384) 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 386).Rim diameter
The rim diameter4 (
page 384) is the
diameter of the bead seat, not the
diameter of the rim edge. Rim diameter is
indicated in inches (in).
Tire load rating
The tire load rating5 (
page 384) is a
numerical code associated with the
maximum load a tire can support.
For example, a load rating of 91 corre-
sponds to a maximum load of 1356 lbs
(615 kg) the tire is designed to support.
See also “Maximum tire load”
(
page 390) where the maximum load as-
sociated with the load index is indicated in
kilograms and lbs.

391 Operation
Tires and wheels
Always follow the recommended tire
inflation pressure (
page 371) for proper
tire inflation. Uniform 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
applicable, 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.
Warning!G
Never exceed the max. tire inflation
pressure. 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 over-
heated.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride com-
fort, wear unevenly, increase stopping dis-
tance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road de-
bris, potholes etc.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
TreadwearTractionTemperature
200AAA

393 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.
Warning!G
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underin-
flation, or excessive loading, either sepa-
rately or in combination, can cause
excessive heat build-up and possible tire
failure.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.

405 Operation
Vehicle care
Engine cleaning
Prior to cleaning the engine compartment
make sure to protect electrical compo-
nents and connectors from the intrusion of
water and cleaning agents.
Corrosion protection, such as
MB Anticorrosion Wax, should be applied
to the engine compartment after every
engine cleaning. Before applying, all con-
trol linkage bushings and joints should be
lubricated. The poly-V-belt and all pulleys
should be protected from any wax.
Vehicle washing
In the winter, thoroughly remove all traces
of road salt as soon as possible.
When washing the vehicle underbody, do
not forget to clean the inner sides of the
wheels.Hand-wash
Do not use hot water or wash your vehicle
in direct sunlight.
Only use a mild car wash detergent,
such as Mercedes-Benz approved Car
Shampoo.
Thoroughly spray the vehicle with a dif-
fused jet of water.
Direct only a very weak spray towards
the ventilation intake.
Use plenty of water and rinse the
sponge and chamois frequently.
Rinse with clean water and thoroughly
dry with a chamois.
Do not allow cleaning agents to dry on
the finish.Automatic car wash
You can have your car washed in an auto-
matic car wash from the start. Automatic
car washes without brushes are prefera-
ble.
To protect the filter system, switch the
climate control system (
page 208) or
the automatic climate control system*
(
page 222) to air recirculation mode.
If the vehicle is very dirty, prewash it
before running it through the automatic
car wash.
iVehicles with KEYLESS-GO*:
If a door handle is hit by a strong jet of water, and
a SmartKey with KEYLESS-GO* is in close
proximity, i.e. within approximately
3 ft (approximately 1 m), the vehicle could be
inadvertently locked or unlocked.
!Do not use scouring agents on these parts.
Never apply strong force and only use a soft,
non-scratching cloth when cleaning the vehicle.
Do not attempt to wipe the surface with a dry
cloth or sponge.
Otherwise you may scratch or damage the paint.
!Do not clean your vehicle in an automatic
touchless car wash which uses caustic spray.
Otherwise the caustic spray will damage the
paint or ornamental moldings.
!Make sure that the windshield wiper switch
is set to0 (
page 60). 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.

534 Technical data
Main Dimensions
ModelR 320 CDI 4MATIC
R 3501
R 350 4MATIC
1USA only.
R 550 4MATIC2
2Canada only.
Overall vehicle length203.7 in (5 173 mm)203.7 in (5 173 mm)
Overall vehicle width (exterior mirrors folded out)85.4 in (2 168 mm)85.4 in (2 168 mm)
Overall vehicle width (exterior mirrors folded in)75.7 in (1 922 mm)75.7 in (1 922 mm)
Overall vehicle height3
3Data apply to unladen vehicles with standard equipment. Data may vary in vehicles equipped with AIRMATIC* depending on the
selected damping settings (page 276) and the current vehicle level (page 277).
65.5 in (1 663 mm)65.6 in (1 666 mm)
Wheelbase126.6 in (3 215 mm)126.6 in (3 215 mm)
Track, front64.7 in (1 643 mm)64.7 in (1 643 mm)
Track, rear64.4 in (1 636 mm)64.4 in (1 636 mm)
Ground clearance35.8 in (148 mm)5.9 in (150 mm)
Turning circle40.7 ft (12.4 m)40.7 ft (12.4 m)