2010 MERCEDES-BENZ R320 Owner's Manual

vehicle. Comply with all relevant safety
precautions.
G
Warning!
To help prevent personal injury, stay clear of
moving parts when the hood is open and the
engine is running.
The radiator fan may continue to run for
approximately 30 seconds or may even
restart after the engine has been turned off.
Stay clear of fan blades. G
Warning!
Vehicles with gasoline engine:
The engine is equipped with a transistorized
ignition system. Because of the high voltage
it is dangerous to touch any components
(ignition coils, spark plug sockets, diagnostic
socket) of the ignition system
R with the engine running
R while starting the engine
R when the ignition is switched on and the
engine is turned manually G
Warning!
Vehicles with diesel engine:
The engine is equipped with a high-voltage
electronic control unit for the injection
system. Because of the high voltage it is
dangerous to touch any components of the
injection system (injectors, electrical wires)
R with the engine running
R while starting the engine
R when the ignition is switched on X
Pull hood lock release lever :.
The hood is unlocked.
! Never open the hood if the wiper arms are
folded forward away from the windshield.
Otherwise the windshield wipers or the
hood could be damaged. X
Press and hold handle ;.
The hood is unlocked.
X Pull up on the hood in direction of arrow
and then release it.
The hood will be held open at shoulder
height by gas-filled struts automatically.
Closing G
Warning!
When closing the hood, use extreme caution
not to catch hands or fingers. Be careful that
you do not close the hood on anyone.
Make sure the hood is securely engaged
before driving off. Do not continue driving if
the hood can no longer engage after an Engine compartment
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accident, for example. The hood could
otherwise come loose while the vehicle is in
motion and injure you and/or others.
X Let the hood drop from a height of
approximately 8 in (20 cm).
X Check to make sure the hood is fully
closed.
If you can raise the hood at a point above
the headlamps, then it is not properly
closed. Open it again and let it drop with
somewhat greater force. Radiator
i Vehicles with diesel engine:
Do not cover the radiator, for example with
a winter front or bug cover. Otherwise the
readings of the on-board diagnostic system
may be inaccurate. Some of theses
readings are required by law and must be
accurate at all times. Engine oil
The amount of oil your engine consumes will
depend on a number of factors, including
driving style. Increased oil consumption can
occur when the vehicle is new or the vehicle
is driven frequently at higher engine speeds.
Engine oil consumption checks should only
be made after the vehicle break-in period.
! Do not use any special lubricant additives,
as these may damage the drive assemblies.
Using special additives not approved by
Mercedes-Benz may cause damage not
covered by the Mercedes-Benz Limited
Warranty.
For further information contact an
authorized Mercedes-Benz Center.
Notes on checking engine oil level When checking the oil level the vehicle must
be parked on level ground and the vehicle must have been stationary for at least
5 minutes with the engine turned off.
Checking engine oil level X
Open the hood (Y page 222). Example illustration: Gasoline engine
Example illustration: Diesel engine
X
Pull out oil dipstick :.
X Wipe oil dipstick : clean.
X Fully insert oil dipstick : into the dipstick
guide tube.
X Pull out oil dipstick : again after
approximately 3 seconds to obtain
accurate reading.
The oil level is correct when it is between
lower (min) mark = and upper (max)
mark ; of oil dipstick :.
i The filling quantity between the upper and
lower marks on the oil dipstick is
approximately 2.1 US qt. (2.0 l).
X If necessary, add engine oil. 224
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For more information on engine oil, see
“Fuels, coolants, lubricants etc.”
(Y page 350).
For information on messages in the
multifunction display concerning engine oil,
see the “Practical hints” section
(Y page 293).
Adding engine oil
!
Only use approved engine oils and oil
filters required for vehicles with
Maintenance System. For a listing of
approved engine oils and oil filters, contact
an authorized Mercedes-Benz Center or
visit www.mbusa.com (USA only).
The following will result in engine or
emission control system damage not
covered by the Mercedes-Benz Limited
Warranty:
R Using engine oils and oil filters of
specification other than those expressly
required for the Maintenance System.
R Changing of oil and oil filter at change
intervals longer than those called for by
the Maintenance System.
R Using any oil additives. Example illustration: R 350
X
Unscrew filler cap : from filler neck.
X Add engine oil as required. Be careful not
to overfill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water. !
Excess oil must be siphoned or drained
off. It could cause damage to the engine
and emission control system not covered
by the Mercedes-Benz Limited Warranty.
X Screw filler cap : back on filler neck.
For more information on engine oil, see the
“Technical data” section ( Y page 350) and
(Y page 352). Transmission fluid level
The transmission fluid level does not need to
be checked. If you notice transmission fluid
loss or gearshifting malfunctions, have an
authorized Mercedes-Benz Center check the
transmission. Coolant level
The engine coolant is a mixture of water and
anticorrosion/antifreeze.
When checking the coolant level, the vehicle
must be parked on level ground, and the
coolant temperature must be below 158‡
(70†). G
Warning!
In order to avoid any potentially serious burns:
R 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.
R Do not remove the cap on the coolant
expansion tank if the coolant temperature
is above 158‡ (70†). Allow the engine to
cool down before removing the cap. The
coolant expansion tank contains hot fluid
and is under pressure.
R Using a rag, slowly open the cap
approximately 1
/ 2 turn to relieve excess
pressure. If opened immediately, scalding Engine compartment
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hot fluid and steam will be blown out under
pressure.
R Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. X
Using a rag, slowly open cap ;
approximately 1
/ 2 turn to relieve excess
pressure.
X Continue turning cap ; counterclockwise
and remove it.
The coolant level is correct if the level
R for cold coolant: reaches marking
bar : in coolant expansion tank =
R for warm coolant: is approximately 0.6 in
(1.5 cm) higher
X Add coolant as required.
X Screw cap ; back on and tighten it.
For more information on coolant, see the
“Technical data” section ( Y page 351) and
(Y page 355). Washer system and headlamp
cleaning system
G
Warning!
Washer solvent/antifreeze is highly
flammable. Do not spill washer solvent/
antifreeze on hot engine parts, because it may
ignite and burn. You could be seriously
burned. !
Always use washer solvent/antifreeze
where temperatures may fall below
freezing point. Failure to do so could result
in damage to the washer system/fluid
reservoir.
! Only use washer fluid which is suitable for
plastic lenses. Improper washer fluid can
damage the plastic lenses of the
headlamps.
! Do not use distilled or deionized water in
the washer fluid reservoir. Otherwise, the
washer fluid level sensor could be
damaged. Fluid for the washer system, rear window
washer system, and the headlamp cleaning
system is supplied from washer fluid
reservoir ;.
During all seasons, use MB Windshield
Washer Concentrate “MB SummerFit”. Mix it
with water or premixed washer solvent/
antifreeze depending on the ambient
temperature (
Y page 357).
X Opening washer fluid reservoir: Pull tab
of cap : upwards.
X Refill the washer fluid reservoir.
X Closing washer fluid reservoir: Press
cap : onto filler hole until it engages.
For more information, see “Washer system
and headlamp cleaning system”
(Y page 351). 226
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Brake fluid level
! 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
immediately. Contact an authorized
Mercedes-Benz Center immediately. Do
not add brake fluid as this will not solve the
problem. For more information, see
“Practical hints”.
When checking the brake fluid level, the
vehicle must be parked on level ground. The brake fluid level is correct when it is
between lower mark (MIN)
; and upper
mark (MAX) : of the brake fluid reservoir. Tires and wheels
Safety notes
Contact an authorized Mercedes-Benz 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. G
Warning!
Replace rims or tires with the same
designation, manufacturer and type as shown
on the original part. For further information
contact an authorized Mercedes-Benz Center.
If incorrectly sized rims and tires are
mounted, the wheel brakes or suspension
components can be damaged. Also, the operating clearance of the wheels and the
tires may no longer be correct.
G
Warning!
Worn, old tires can cause accidents. If the tire
tread is worn to minimum tread depth, 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
recommended 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. G
Warning!
If you feel a sudden significant vibration or
ride disturbance, or you suspect that possible
damage to your vehicle has occurred, you
should turn on the hazard warning flashers,
carefully slow down, and drive with caution to
an area which is a safe distance from the road.
Inspect the tires and the vehicle underbody
for possible damage. If the vehicle or tires
appear unsafe, have the vehicle towed to the
nearest authorized Mercedes-Benz Center or
tire dealer for repairs. G
Warning!
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
could lose control of the vehicle. Continued
driving with a flat tire or driving at high speed
with a flat tire will cause excessive heat build-
up and possibly a fire. Important guidelines
R Only use sets of tires and rims of the same
type and make.
R Tires must be of the correct size for the rim. Tires and wheels
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R
Break in new tires for approximately
60 miles (100 km) at moderate speeds.
R Regularly check the tires and rims for
damage.
Dented or bent rims can cause tire
inflation pressure loss and damage to the
tire beads.
R If the vehicle is heavily loaded, check tire
inflation pressure and correct as required.
R 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
/ 8 in (3 mm).
R When replacing individual tires, you should
mount new tires on the front wheels first
(on vehicles with same-sized wheels all
around). Recommended tire inflation pressure
G
Warning!
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 overheated.
Do

not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver’s door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
Your vehicle is equipped with the Tire and
Loading Information placard located on the
driver’s door B-pillar ( Y page 236). The tire inflation pressure should be checked
regularly. Only adjust the tire inflation
pressure on cold tires. The tires can be
considered cold if the vehicle has been
parked

for at least 3 hours or driven less than
1 mile (1.6 km). Depending on the ambient
temperature, the driving speed and the tire
load, the tire temperature changes. When the
tire temperature changes by 18‡ (10†), the
tire inflation pressure will change by
approximately 1.5 psi (0.1 bar). Keep this in
mind when checking tire inflation pressure on
warm tires and adjust the tire pressure only
if the tire inflation pressure is too low for the
current operating conditions. If you check the
tire inflation pressure when the tires are
warm, the reading will be higher than the cold
reading. This is normal. Do not let air out to
match the specified cold tire inflation
pressure. Otherwise, the tire will be
underinflated.
Follow recommended cold tire inflation
pressures listed on Tire and Loading
Information placard on the driver’s door
B-pillar.
Keeping the tires properly inflated provides
the best handling, tread life and riding
comfort.
In addition to the Tire and Loading
Information placard on the driver’s door
B-pillar, also consult the tire inflation
pressure label on the inside of the filler flap
for any additional information pertaining to
special driving situations. For more
information, see “Important notes on tire
inflation pressure” ( Y page 229).
i Data shown on Tire and Loading
Information placard example are for
illustration purposes only. Tire data are
specific to each vehicle and may vary from
data shown in the following illustration.
Refer to Tire and Loading Information
placard on vehicle for actual data specific
to your vehicle. 228
Tires and wheels
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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 G
Warning!
If the tire inflation pressure drops repeatedly,
check the tires for punctures from foreign
objects and/or whether air is leaking from the
valves or from around the rim.
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 on how to adjust the cold
tire inflation pressure. If you do not adjust the
tire inflation pressure, excessive heat can
build up and result in sudden tire failure.
If you are not sure about the proper tire
inflation, contact an authorized Mercedes-
Benz Center.
i Driving 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. Make sure to readjust the tire inflation
pressure for normal driving speeds.
Supplemental tire inflation pressure
information for different loading conditions of
the vehicle can be found on the tire inflation
pressure label. The tire inflation pressure
label is located on the inside of the fuel filler
flap.
For the tire inflation pressure for spare
wheels such as Minispare wheels or spare
wheels with collapsible tire refer to
R
the yellow label on the spare wheel rim
R the “Technical data” section of this
Operator’s Manual ( Y page 350)
R the Tire and Loading Information placard on
the driver’s door B-pillar
For the tire inflation pressure for full-size
spare wheels refer to
R the Tire and Loading Information placard on
the driver’s door B-pillar
R the tire inflation pressure label on the
inside of the fuel filler flap
Unless specified otherwise, the tire inflation
pressures on the tire inflation pressure label
are valid for all approved, factory-equipped
tires. When a tire size is specified, the tire
inflation pressure that follows applies to that
particular tire size only.
i Data shown on tire inflation pressure
label examples are for illustration purposes
only. Tire inflation pressure data are
specific to each vehicle and may vary from
data shown in the following illustrations.
Refer to the tire inflation pressure label on
vehicle for actual data specific to your
vehicle. Tires and wheels
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Example illustration: Tire inflation pressures for all
approved, factory equipped tires
Some tire inflation pressure labels may only
show the rim diameter instead of the entire
tire size, e.g. R 18 or 18".
The rim diameter is part of the tire size as
specified on the tire sidewall (Y page 245).
Example illustration: Tire inflation pressures
specific to rim diameter
i
When towing a trailer, inflate the tires to
the tire inflation pressure as specified for a
fully loaded vehicle.
Potential problems associated with
underinflated and overinflated tires Underinflated tires
G
Warning!
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 overheated. Underinflated tires can
R
cause excessive and uneven tire wear
R adversely affect fuel economy
R lead to tire failure from being overheated
R adversely affect handling characteristics
Overinflated tires G
Warning!
Follow recommended tire inflation pressures.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
Overinflated tires can
R adversely affect handling characteristics
R cause uneven tire wear
R be more prone to damage from road
hazards
R adversely affect ride comfort
R increase stopping distance Checking tire inflation pressure
Safety notes G
Warning!
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 overheated.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc. 230
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