2008 MERCEDES-BENZ C300 4MATIC engine

326 Operation
Engine compartment
The hood lock release lever is located to
the left of the steering wheel under the
dashboard.
1Release lever
Pull release lever 1 downwards.
The hood is unlocked.2Lever for opening the hood
Push lever2 under the hood upwards.
Pull up on the hood and then release it.
The hood will be automatically held
open at shoulder height by gas-filled
struts. Closing
Let the hood drop from a height of ap-
proximately 1 ft (30 cm).
The hood will lock audibly.
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.
!To avoid damage to the windshield wipers or
hood, never open the hood if the wiper arms are
folded forward away from the windshield.
Warning!G
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 be-
fore driving off. Do not continue driving if the
hood can no longer engage after an acci-
dent, for example. The hood could otherwise
come loose while the vehicle is in motion
and endanger you and/or others.

327 Operation
Engine compartment
Engine oil
The amount of oil your engine needs will
depend on a number of factors, including
driving style. Higher oil consumption can
occur when

the vehicle is new

the vehicle is driven frequently at
higher engine speeds
Engine oil consumption checks should only
be made after the vehicle break-in period.Notes about checking engine oil level
When checking the oil level

the vehicle must be parked on level
ground

with the engine at operating tempera-
ture, the vehicle must have been
stationary for at least 5 minutes with
the engine turned off

with the engine not at operating tem-
perature yet, the vehicle must have
been stationary for at least 30 minutes
with the engine turned offChecking engine oil level with the oil
dipstick
To check the engine oil level with the oil
dipstick, do the following:
Open the hood (page 325).
1Oil dipstick
2Upper mark
3Lower mark
Pull out oil dipstick1.
Wipe oil dipstick1 clean.
Fully insert oil dipstick1 into the dip-
stick guide tube.
!Do not use any special lubricant additives,
as these may damage the drive assemblies. Us-
ing special additives not approved by
Mercedes-Benz may cause damage not covered
by the Mercedes-Benz Limited Warranty.
More information on this subject is available at
any Mercedes-Benz Center.


328 Operation
Engine compartment
Pull out oil dipstick1 again after ap-
proximately 5 seconds to obtain accu-
rate reading.
The oil level is correct when it is between
lower mark3 (min.) and upper mark2
(max.) of the oil dipstick.
If necessary, add engine oil.
For adding engine oil (
page 328).
For more information on engine oil, see the
“Technical data” section (
page 476) and
(
page 480).
For more information on messages in the
multifunction display concerning engine
oil, see the “Practical hints” section
(
page 387).Adding engine oil
1Filler cap
Unscrew filler cap1 from filler neck.
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.
Screw filler cap1 back on filler neck.
For more information on engine oil, see the
“Technical data” section (
page 476) and
(
page 480).
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 Center
check the transmission.
iThe filling quantity between the upper and
lower marks on the oil dipstick is approximately
2.1 US qt. (2.0 l).
!Only use approved engine oils and oil filters
required for vehicles with Maintenance System.
For a listing of approved engine oils and oil fil-
ters, refer to the Factory Approved Service Prod-
ucts pamphlet (USA only) in your vehicle
literature portfolio, or contact an authorized
Mercedes-Benz Center.
Using engine oils and oil filters of specification
other than those expressly required for the Main-
tenance System, or changing 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.
!Excess oil must be siphoned or drained off.
It will cause damage to the engine and emission
control system not covered by the
Mercedes-Benz Limited Warranty.


329 Operation
Engine compartment
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 and the engine
must be cool.
The coolant expansion tank is located on
the passenger side of the engine compart-
ment.
1Cap
2Coolant expansion tank
3Fluid level bridgeUsing a rag, turn cap1 slowly approx-
imately a half-turn counterclockwise to
release any excess pressure.
Continue turning the cap1 counter-
clockwise and remove it.
The coolant level is correct if the level

for cold coolant: reaches the white
marking (plastic bridge)3 inside the
coolant expansion tank2

for warm coolant: is approximately
0.6 in (1.5 cm) higher
Add coolant as required.
Replace and tighten cap1.
For more information on coolant, see the
“Technical data” section (
page 484).
Warning!G
In order to avoid 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 gauge indi-
cates 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 a half-turn to relieve excess
pressure. If opened immediately, scald-
ing hot fluid and steam will be blown out
under pressure.

Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene gly-
col which may burn if it comes into con-
tact with hot engine parts.

330 Operation
Engine compartment
Windshield washer system and
headlamp cleaning system*
The washer fluid reservoir is located on the
left-hand side of the engine compartment
when looking in the direction of travel. It
supplies the windshield washer system
and headlamp cleaning system with wash-
er fluid.
1Cap
Fluid for the windshield washer system and
the headlamp cleaning system is supplied
from the windshield washer reservoir. It
has a capacity of approximately 6.34 US qt
(6.0 l).During all seasons, add MB Windshield
Washer Concentrate “MB SummerFit” to
water. Premix the windshield washer fluid
in a suitable container.
To open washer fluid reservoir: Pull
tab of cap1 upward.
Refill the reservoir with MB Windshield
Washer Concentrate and water (or
commercially available premixed wind-
shield washer solvent/antifreeze, de-
pending on ambient temperatures).
To close washer fluid reservoir:
Press cap1 onto filler hole until it en-
gages.
For more information, see “Windshield
washer system and headlamp cleaning
system*” (
page 486).
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.
!Always use washer solvent/antifreeze
where temperatures may fall below freezing
point. Failure to do so could result in damage to
the washer system/reservoir.
!Only use washer fluid which is suitable for
plastic lenses. Improper washer fluid can dam-
age the plastic lenses of the headlamps.

360 Operation
Winter driving
Before the onset of winter, have your
vehicle winterized at an authorized
Mercedes-Benz 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 Windshield
Washer Concentrate “MB Summerfit”
to a premixed windshield washer sol-
vent/antifreeze which is formulated for
below freezing temperatures
(
page 485).

Battery test. Battery capacity drops
with decreasing ambient temperature.
A well charged battery helps to make
sure 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 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, EBP,
ESP
® and 4MATIC in winter operation.
For safe handling, make sure all mounted
winter tires 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
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.

363 Operation
Maintenance
Maintenance service term exceeded
If you have exceeded the suggested main-
tenance service term, you will see the fol-
lowing message in the multifunction
display:
Service A Exceeded by XXXX miles (km)
Service A Exceeded by XXX days
In addition, a signal sounds when the mes-
sage appears.
Any authorized Mercedes-Benz Center will
reset the maintenance service indicator
following a completed maintenance
service.
Calling up the maintenance service
indicator display
You can call up the maintenance service in-
dicator display at any time to check when
the next maintenance service is due.
Switch on the ignition.
The standard display of the control sys-
tem appears (
page 156).
Press ( or & on multifunction
steering wheel to select
Service menu.
Press % or $ to select the main-
tenance service indicator display.
Press #.
The service deadline appears in the
multifunction display.Resetting the maintenance service
indicator
In the event that the maintenance service
on your vehicle is not carried out at an
authorized Mercedes-Benz Center, you can
have the maintenance service indicator
reset. The automotive maintenance facility
carrying out the maintenance service will
find the information for resetting the
maintenance service indicator in the
maintenance-relevant information for your
vehicle. Such information is available from
either your authorized Mercedes-Benz
Center or directly from Mercedes-Benz.
iThe menu overview can be found on
(
page 154).
iIf the battery is disconnected, the days of
disconnection will not be included in the count
shown by the maintenance service indicator.
To arrive at the true maintenance service
deadline, you will need to subtract these days
from the days shown in the maintenance service
indicator message or maintenance service
indicator display.
iIf the maintenance service indicator was
inadvertently reset, have an authorized
Mercedes-Benz Center correct it.
Only reset if the proper maintenance service has
been performed. Resetting the system without
performing the proper service as called for by
the maintenance service indicator will result in
engine damage and/or other vehicle damage not
covered by the Mercedes-Benz Limited
Warranty.

366 Operation
Vehicle care
Engine cleaning
Prior to cleaning the engine compartment,
make sure to protect electrical compo-
nents and connectors from contact with
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
control linkage bushings and joints should
be lubricated. The poly-V-belt and all pul-
leys 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.
iVehicles with KEYLESS-GO* (Canada only):
If a door handle is hit by a strong jet of water, and
a SmartKey with KEYLESS-GO* is in close prox-
imity, i.e. within approximately 3 ft (approxi-
mately 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.