2008 MERCEDES-BENZ R320 warning light

360 Operation
Engine compartment
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.
Screw filler cap1 back on filler neck.
For more information on engine oil, see
“Technical data” section (
page 536) and
(
page 538).
Transmission fluid level
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Light
Truck Center check the automatic trans-
mission.Coolant level
The engine coolant is a mixture of water
and anticorrosion/antifreeze. To check
the coolant level, the vehicle must be
parked on level ground.
!Excess oil must be siphoned or drained off.
It could cause damage to the engine or
emission control system not covered by the
Mercedes-Benz Limited Warranty.
Warning!G
In order to avoid any potentially serious
burns:

Use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system,
or if the coolant temperature display
indicates that the coolant is overheated.

Do not remove pressure cap on coolant
reservoir if coolant temperature is
above 158°F (70°C). Allow engine to
cool down before removing cap. The
coolant reservoir contains hot fluid and
is under pressure.

Using a rag, slowly open the cap approx-
imately 1/2turn to relieve excess pres-
sure. If opened immediately, scalding


363 Operation
Tires and wheels
Tires and wheels
Contact an authorized Mercedes-Benz
Light Truck Center for information on
tested and recommended rims and tires
for summer and winter operation. They can
also offer advice concerning tire service
and purchase.Important guidelines

Only use sets of tires and rims of the
same type and make.

Tires must be of the correct size for the
rim.

Break in new tires for approximately
60 miles (100 km) at moderate
speeds.

Regularly check the tires and rims for
damage. Dented or bent rims can
cause tire inflation pressure loss and
damage to the tire beads.

If vehicle is heavily loaded, check tire
inflation pressure and correct as
required.

Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths of less than
1/8in (3 mm).

When replacing individual tires, you
should mount new tires on the front
wheels first (on vehicles with
same-sized wheels all around).
Warning!G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. See an authorized
Mercedes-Benz Light Truck Center for
further information. If incorrectly sized rims
and tires are mounted:

The wheel brakes or suspension
components can be damaged.

The operating clearance of the wheels
and the tires may no longer be correct.
Warning!G
Worn, old tires can cause accidents. If the
tire tread is badly worn, 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 recom-
mended 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.

365 Operation
Tires and wheels
Tread depth
Do not allow your tires to wear down too
far. Adhesion properties on wet roads are
sharply reduced at tread depths of less
than
1/8in (3 mm).
Treadwear indicators (TWI) are required by
law. These indicators are located in six
places on the tread circumference and
become visible at a tread depth of approx-
imately
1/16in (1.6 mm), at which point the
tire is considered worn and should be re-
placed.
Recommended minimum tire tread depth:

Summer tires 1/8in (3 mm)

Winter tires 1/6in (4 mm)
1TWI (T
read Wear Indicator)
The treadwear indicator appears as a solid
band across the tread.Storing tires
Cleaning tires
Direction of rotation
Unidirectional tires offer added advan-
tages, such as better hydroplaning perfor-
mance. To benefit, however, you must
make sure the tires rotate in the direction
specified.
An arrow on the sidewall indicates the
intended direction of rotation (spinning) of
the tire.
Warning!G
Although the applicable federal motor safety
laws consider a tire to be worn when the
treadwear indicators (TWI) become visible at
approximately
1/16in (1.6 mm), we recom-
mend that you do not allow your tires to
wear down to that level. As tread depth
approaches 1/8in (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.!Keep unmounted tires in a cool, dry
place with as little exposure to light as possible.
Protect tires from contact with oil, grease and
fuels.
!Never use a round nozzle to power wash
tires. The intense jet of water can result in
damage to the tire.
Always replace a damaged tire.

372 Operation
Tires and wheels
The Tire and Loading Information placard
lists the recommended cold tire inflation
pressures for maximum loaded vehicle
weight. The tire inflation pressures listed
apply to the tires installed as original
equipment.
Important notes on tire inflation
pressure
Tire temperature and tire inflation pressure
are also increased while driving, depending
on the driving speed and the tire load.If you will be driving your vehicle at high
speeds of 100 mph (160 km/h) or higher,
where it is legal and conditions allow,
consult the tire inflation pressure label on
the inside of the fuel filler flap (if available)
on how to adjust the cold tire inflation
pressure. If you do not adjust the tire infla-
tion pressure, excessive heat can build up
and result in sudden tire failure.
If your vehicle is not equipped with the tire
inflation pressure label on the inside of the
fuel filler flap, contact an authorized
Mercedes-Benz Light Truck Center for
proper tire inflation pressure.Make sure to readjust the tire inflation
pressure for normal driving speeds. You
should wait until the tires are cold before
adjusting the tire inflation pressure.
Some vehicles may have supplemental tire
inflation pressure information for vehicle
loads less than the maximum loaded vehi-
cle condition. If such information is provid-
ed, it can be found on the tire inflation
pressure label located on the inside of the
fuel filler flap (
page 352).
Tire inflation pressure changes by approxi-
mately 1.5 psi (0.1 bar) per 18°F (10°C) of
air temperature change. Keep this in mind
when checking tire inflation pressure
where the temperature is different from
the outside temperature.Warning!G
If the tire inflation pressure drops
repeatedly:

Check the tires for punctures from
foreign objects.

Check to see whether air is leaking from
the valves or from around the rim.
iDriving comfort may be reduced when the
tire inflation pressure is adjusted to the value for
speeds above 100 mph (160 km/h) as specified
on the tire inflation pressure label located on the
inside of the fuel filler flap.

398 Operation
Winter driving
Before the onset of winter, have your
vehicle winterized at an authorized
Mercedes-Benz Light Truck Center. This
service includes:

Check of anticorrosion and antifreeze
concentration.

Addition of cleaning concentrate to the
water of the windshield and headlamp
cleaning system. Add MB Concentrate
“MB SummerFit” to a premixed wind-
shield washer solvent/antifreeze
which is formulated for temperatures
below freezing point (
page 544).

Battery test. Battery capacity drops
with decreasing ambient temperature.
A well charged battery helps to make
sure that the engine can be started
even at low ambient temperatures.

Tire change.
Winter tires
Always use winter tires at temperatures
below 45°F (7°C) and whenever wintry
road conditions prevail. Not all M+S rated
tires provide special winter performance.
Make sure the tires you use show M+S and
the mountain/snowflake marking.on
the tire sidewall. These tires meet specific
snow traction performance requirements
of the Rubber Manufacturers Association
(RMA) and the Rubber Association of Can-
ada (RAC) and have been designed specif-
ically for use in snow conditions. Use of
winter tires is the only way to achieve the
maximum effectiveness of the ABS, ESP
®,
4-ETS, and EBP in winter operation.
For safe handling, make sure all winter
tires mounted are of the same make and
have the same tread design.Always observe the speed rating of the
winter tires installed on your vehicle. If the
maximum speed for which your tires are
rated is below the speed rating of your
vehicle, you must place a notice to this
effect where it will be seen by the driver.
Such notices are available at your tire
dealer or any authorized Mercedes-Benz
Light Truck Center.
Warning!G
Winter tires with a tread depth of less than 1/6in (4 mm) must be replaced. They are no
longer suitable for winter operation.

399 Operation
Winter driving
Snow chains
Snow chains should only be driven on
snow-covered roads at speeds not to
exceed 30 mph (50 km/h). Remove chains
as soon as possible when driving on roads
without snow.
Please observe the following guidelines
when using snow chains:

Use of snow chains is not permissible
with all wheel/tire combinations
(
page 529).

Use snow chains in pairs and on rear
wheels only. Follow the manufacturer’s
mounting instructions.

Only use snow chains that are
approved by Mercedes-Benz. Your
authorized Mercedes-Benz Light Truck
Center will be glad to advise you on this
subject.

Use of snow chains may be prohibited
depending on location. Always check
local and state laws before installing
snow chains.

Do not use snow chains on the spare
wheel (
page 532).
Warning!G
If you use your spare tire when winter tires
are fitted on the other wheels, be aware that
the difference in tire characteristics may
very well impair turning stability and that
overall driving stability may be reduced.
Adapt your driving style accordingly.
Have the spare tire replaced with a winter
tire at the nearest authorized
Mercedes-Benz Light Truck Center.!Vehicles with Adaptive Damping
System (ADS)*: When driving with snow chains,
do not select SPORT mode (
page 276) as this
could result in damage to the vehicle.
!Some tire sizes do not leave adequate clear-
ance for snow chains. To help avoid serious dam-
age to your vehicle or tires, use of snow chains is
not permissible with the spare wheel.
!If snow chains are mounted to the front
wheels, they may scrape against the body or axle
components. The tires or the vehicle could be
damaged as a result.
iWhen driving with snow chains, you may
wish to deactivate the ESP® (page 104)
before setting the vehicle in motion. This will
improve the vehicle’s traction.

410 Operation
Vehicle care
Cleaning the panorama roof with
tilt/sliding panel*
The rear part of the panorama roof has a
protective layer on the inside.
Use a soft, clean cloth and a mild
window cleaning solution.
An automotive glass cleaner is recom-
mended.Light alloy wheels
If possible, clean wheels once a week.
Use Mercedes-Benz approved Wheel
Care, a soft bristle brush and a strong
spray of water for cleaning the light al-
loy wheels.Plastic and rubber parts
Use a gentle dishwashing detergent or
mild detergent for delicate fabrics as a
washing solution.
Wipe with a cloth moistened in a luke-
warm solution.
The surface may temporarily change
color. If this is the case, wait for it to
dry.
!Do not use a dry cloth, abrasives, solvents
or cleaners containing solvents. Do not touch
the protective layer with hard objects such as an
ice scraper or ring. Never apply strong force and
only use a soft, non-scratching cloth when clean-
ing the rear part of the tilt/sliding panel*.
Otherwise you may scratch or damage the
protective layer.
!Only use acid-free cleaning materials. Acid
may cause corrosion or damage the clear coat.
!The vehicle should not be parked for an
extended period of time immediately after it has
been cleaned, especially not after the wheel rims
have been cleaned with wheel rim cleaner.
Wheel rim cleaners can lead to increased
corrosion of the brake disks and brake pads.
Non-approved wheel cleaners may also damage
the wheel paint if the car is not driven after
cleaning. Therefore, the vehicle’s brake system
should always be warmed-up before it is parked
after cleaning. To do so, please drive your vehicle
for several minutes to allow the brakes to dry.
When applying Mercedes-Benz approved Tire
Care and Mercedes-Benz approved Wheel Care
products, take care not to spray them on the
brake disks.
Warning!G
Do not use cleaners containing solvents or
cockpit care sprays to clean the cockpit or
the steering wheel. Cleaners containing sol-
vents will make the surface porous and vehi-
cle occupants could suffer serious injuries
from plastic parts coming loose in the event
of air bag deployment.

411 Operation
Vehicle care
Hard plastic trim items
Use Mercedes-Benz approved Interior
Care, a soft, lint-free cloth and apply
with light pressure.
Steering wheel
Wipe with a damp cloth and dry thor-
oughly or clean with Mercedes-Benz
approved Leather Care.Carpets
Use Mercedes-Benz approved Carpet
and Fabric Care for cleaning the
carpets.
Headliner
Use a soft bristle brush or a
dry-shampoo cleaner in case of
excessive dirt.
Seat belts
Only use clear, lukewarm water and
soap.Upholstery
Using aftermarket seat covers or wearing
clothing that have the tendency to give off
coloring (e.g. when wet, etc.) may cause
the upholstery to become permanently dis-
colored. By lining the seats with a proper
intermediate cover, contact-discoloration
will be prevented.
!Never apply strong force and only use a soft,
non-scratching cloth when cleaning the surface.
Do not attempt to wipe the surface with a dry
cloth or sponge.
Otherwise you may scratch or damage the
surface.
!The seat belts must not be treated with
chemical cleaning agents. Do not dry the seat
belts at temperatures above 176°F (80°C) or in
direct sunlight.
Warning!G
Do not bleach or dye seat belts as this may
severely weaken them. In a crash they may
not be able to provide adequate protection.
Warning!G
Only use seat or head restraint covers which
have been tested and approved by
Mercedes-Benz for your vehicle model.
Using other seat or head restraint covers
may interfere with or prevent

deployment of the front side impact air
bags

deployment of the rear side impact air
bags*

activation of the active head restraints
Contact an authorized Mercedes-Benz Light
Truck Center for availability.