2008 MERCEDES-BENZ R320 coolant temperature

350 Operation
Driving instructions
Emission control
Certain engine systems serve to keep the
toxic components of the exhaust gases
within permissible legal limits.
These systems, of course, will function
properly only when maintained strictly
according to factory specifications.
Any adjustments on the engine should
therefore be carried out only by qualified
Mercedes-Benz Light Truck Center
authorized technicians.
Engine adjustments should not be altered
in any way. Moreover, the specified service
jobs must be carried out regularly accord-
ing to Mercedes-Benz servicing require-
ments. For details refer to the
Maintenance Booklet.Coolant temperature
During severe operating conditions and
stop-and-go city traffic, the coolant
temperature may rise to approximately
248°F (120°C).
The engine should not be operated
with the coolant temperature above
248°F (120°C). Doing so may cause seri-
ous engine damage which is not covered
by the Mercedes-Benz Limited Warranty.
Warning!G
Inhalation of exhaust gas is hazardous to
your health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause un-
consciousness and possible death.
Do not run the engine in confined areas
(such as a garage) which are not properly
ventilated. If you think that exhaust gas
fumes are entering the vehicle while driving,
have the cause determined and corrected
immediately. If you must drive under these
conditions, drive only with at least one win-
dow fully open at all times.

354 Operation
At the gas station
Low outside temperatures
(diesel engine)
To prevent malfunctions, diesel fuel with
improved cold flow characteristics is of-
fered in the winter months. Check with
your fuel retailer.Check regularly and before a long trip
Open the hood (page 356).
Example illustration R 350 4MATIC
1Coolant level
2Brake fluid
3Windshield washer system and
headlamp cleaning system*
iDiesel engine:
If you have driven the vehicle until the tank was
empty, the fuel system needs to be bled
(
page 502).
!Diesel engine:
The engine is more susceptible to wear and
damage if you use

marine diesel fuel

heating oil

additives
The exhaust aftertreatment device will be
seriously damaged if you use

LOW SULFUR HIGHWAY DIESEL FUEL
(500 ppm SULFUR MAXIMUM)

any other diesel fuel with a sulfur content of
above 15 ppm
The use of such non-approved fuels and/or
special additives is not covered by the
Mercedes-Benz Limited Warranty.
!Do not fill the tank with gasoline. Do not
blend diesel fuel with gasoline or kerosine. The
fuel system and engine will otherwise be dam-
aged, which is not covered by the
Mercedes-Benz Limited Warranty.


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


449 Practical hints
What to do if …
During severe operation conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 248°F (120°C).
Display symbolDisplay messagePossible cause/consequencePossible solution
Observe the coolant temperature in the
multifunction display (
page 164).
If the temperature rises again:
Contact an authorized
Mercedes-Benz Light Truck Center
immediately.
Warning!G

Driving when your engine is overheated
can cause some fluids which may have
leaked into the engine compartment to
catch fire. You could be seriously
burned.

Steam from an overheated engine can
cause serious burns and can occur just
by opening the engine hood. Stay away
from the engine if you see or hear steam
coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.
!The engine should not be operated with the
coolant temperature above 248°F (120°C).
Doing so may cause serious damage which is
not covered by the Mercedes-Benz Limited
Warranty.

537 Technical data
Fuels, coolants, lubricants, etc.
ModelCapacityFuels, coolants, lubricants, etc.
Power steeringapprox. 1.3 US qt (1.2 l)MB Power Steering Fluid or approved
Dexron III ATF
Front wheel hubsapprox. 1.5 oz (43 g) eachHigh temperature roller bearing grease
Brake systemMB Brake Fluid (DOT 4+)
Cooling systemR 320 CDI 4MATIC10.0 US qt (9.5 l)MB Anticorrosion/Antifreeze
R 3501, R 350 4MATIC
1USA only.
10.0 US qt (9.5 l)
R 550 4MATIC2
2Canada only.
12.7 US qt (12 l)
Fuel tank
including a reserve of21.1 US gal (80.0 l)
approx. 3.4 US gal (13.0 l)Gasoline engine:
Premium unleaded gasoline:
Minimum Posted Octane 91
(Avg.of96RON/86MON)
Diesel engine:
ULTRA-LOW SULFUR HIGHWAY DIESEL
FUEL (15 ppm SULFUR MAXIMUM)

538 Technical data
Fuels, coolants, lubricants, etc.
Engine oils
Engine oils are specifically tested for their
suitability in our engines and durability for
our service intervals. Therefore, only use
approved engine oils and oil filters
required for vehicles with Maintenance
System. For a listing of approved engine
oils and oil filters, refer to the Factory
Approved Service Products pamphlet (USA
only), or contact an authorized
Mercedes-Benz Light Truck Center.Engine oil additives
Air conditioning refrigerant
R-134a (HFC) refrigerant and special PAG
lubricating oil are used in the air condition-
ing system.
ModelCapacityFuels, coolants, lubricants, etc.
Air conditioning systemR-134a refrigerant and special PAG lubricant
oil (never R-12)
Windshield washer
system and headlamp
cleaning system*8.0 US qt (7.6 l)MB Windshield Washer Concentrate1
1Use MB Windshield Washer Concentrate “MB SummerFit” and water for temperatures above freezing point or MB Windshield Washer Concentrate “MB SummerFit”
and commercially available premixed windshield washer solvent/antifreeze for temperatures below freezing point. Follow suggested mixing ratios (page 544).
!Using engine oils and oil filters of
specification other than those expressly
required for the Maintenance System, or chang-
ing of oil and oil filter at change intervals longer
than those called for by the Maintenance System
will result in engine or emission control system
damage not covered by the Mercedes-Benz
Limited Warranty.
Please follow Maintenance System recommen-
dations for scheduled oil changes. Failure to do
so will result in engine or emission control
system damage not covered by the
Mercedes-Benz Limited Warranty.
!Do not blend oil additives with engine oil.
They may damage the engine.
Damage or malfunctions resulting from blending
oil additives are not covered by the
Mercedes-Benz Limited Warranty.
!Never use R-12 (CFC) or mineral-based
lubricating oil. Otherwise damage to the system
will occur.

542 Technical data
Fuels, coolants, lubricants, etc.
Coolant system design and coolant used
determine the replacement interval. The
replacement interval published in the
Maintenance Booklet is only applicable if
MB 325.0 Anticorrosion/Antifreeze solu-
tion or other Mercedes-Benz approved
products of equal specification are used to
renew the coolant concentration or bring it
back up to the proper level.
For information on other Mercedes-Benz
approved products of equal specification,
refer to the Factory Approved Service
Products pamphlet (USA only) or contact
an authorized Mercedes-Benz Light Truck
Center.To provide important corrosion protection,
the solution must be at least
50% anticorrosion/antifreeze (equivalent
to freeze protection to approximately
-35°F [-37°C]). If you use a solution that is
more than 55% anticorrosion/antifreeze
(freeze protection to approximately
-49°F [-45°C]), the engine temperature
will increase due to the lower heat transfer
capability of the solution.
Therefore, do not use more than this
amount of anticorrosion/antifreeze.
If the coolant level is low, water and
MB 325.0 Anticorrosion/Antifreeze
should be used to bring it up to the proper
level (have cooling system checked for
signs of leakage). Please make sure the
mixture is in accordance with label
instructions.The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water. If you
are not sure about the water quality,
consult an authorized Mercedes-Benz
Light Truck Center.

544 Technical data
Fuels, coolants, lubricants, etc.
Windshield washer system and
headlamp cleaning system*
Both the windshield washer system and
headlamp cleaning system* are supplied
from the windshield washer reservoir.
The windshield washer reservoir has a ca-
pacity of approximately 8.0 US qt (7.6 l).
Refill the reservoir with MB Windshield
Washer Concentrate “MB SummerFit”
and water (or concentrate and com-
mercially available premixed wind-
shield washer solvent/antifreeze,
depending on ambient temperatures).Windshield and headlamp washer fluid
mixing ratio
For temperatures above freezing point, use
MB Windshield Washer Concentrate
“MB SummerFit” and water:

1 part “MB SummerFit” to 100 parts
water
(1.34 fl oz [40 ml] “MB SummerFit” to
1gal [4.0l] water)
For temperatures below freezing point,
use MB Windshield Washer Concentrate
“MB SummerFit” and commercially
available premixed windshield washer
solvent/antifreeze:

1 part “MB SummerFit” to 100 parts
solvent
(1.34 fl oz [40 ml] “MB SummerFit” to
1 gal [4.0 l] solvent)Warning!G
Washer solvent/antifreeze is highly flamma-
ble. Do not spill washer solvent/antifreeze
on hot engine parts, because it may ignite
and burn. You could be seriously burned.