2005 MERCEDES-BENZ G55AMG engine

237 Operation
At the gas station
G55AMG1Coolant
2Brake fluidCoolant
For normal replenishing, use water (pota-
ble water quality). For more information,
see “Coolant level” (
page 244) and see
“Fuels, coolants, lubricants, etc.”
(
page 374).
Brake fluidEngine oil level
For more information on engine oil, see
“Engine oil” (
page 239).
Tire inflation pressure
For more information, see “Checking tire
inflation pressure” (
page 259).
Vehicle lighting
Check function and cleanliness. For infor-
mation on replacing light bulbs, see “Re-
placing bulbs” (
page 333).
For more information, see “Exterior lamp
switch” (
page 110).
Windshield/rear window washer sys-
tem and headlamp cleaning system
For more information on refilling the reser-
voir, see “Windshield/rear window washer
system and headlamp cleaning system”
(
page 245).
iOpening the hood, see (
page 238).
!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. Noti-
fy an authorized Mercedes-Benz Light
Truck Center immediately. Do not add
brake fluid as this will not solve the
problem. For more information, see
“Practical hints” (
page 290).

238 OperationEngine compartmentHood
Opening
The pull release lever is under the driver’s
side of the instrument panel.
1Release lever

Pull release lever1 upward.
The hood is unlocked.
2Safety hook

Lift hood up slightly.

Pull safety hook2 in direction of ar-
row and open hood.
Warning!
G
Do not pull the release lever while the vehi-
cle is in motion. Otherwise the hood could
be forced open by passing air flow.
!To avoid damage to the windshield wip-
ers or hood, open the hood only with
wipers in parked position.
Warning!
G
To help prevent personal injury, stay clear of
moving parts when the hood is open and the
engine is running. Make sure the hood is
properly closed before driving. When closing
the hood, use extreme caution not to catch
hands or fingers.
The radiator fan may continue to run for ap-
proximately 30 seconds or even restart af-
ter the engine has been turned off. Stay
clear of fan blades.Warning!
G
If you see flames or smoke coming from the
engine compartment, or if the coolant tem-
perature display indicates that the engine is
overheated, do not open the hood. Move
away from vehicle and do not open the hood
until the engine has cooled down. If neces-
sary, call the fire department.

239 Operation
Engine compartment
Closing
Lower hood and let it drop into lock
from a height of approximately 0.7 ft
(20 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 turn signals to the left and
right of the hood, then it is not properly
closed. Open it again and let it drop
with somewhat greater force.
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.
Warning!
G
The engine is equipped with a transistorized
ignition system. Because of the high voltage,
it is dangerous to touch any components (ig-
nition coils, spark plug sockets, diagnostic
socket) of the ignition system

with the engine running


while starting the engine


if ignition is “on” and the engine is
turned manually
Warning!
G
Be careful that you do not close the hood on
anyone.!Do not push the hood closed manually,
as this could damage it.
iDo not use any special lubricant addi-
tives, 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.
More information on this subject is
available at any Mercedes-Benz Light
Truck Center.

240 OperationEngine compartmentChecking engine oil level with the
control system
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 sta-
tionary for at least five 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 off
To check the engine oil level via the
multifunction display, do the following:

Switch on the ignition (
page 35).
The standard display (
page 123) should
appear in the multifunction display.

Press buttonk orj on the
steering wheel until the following
message is seen in the multifunction
display:ENGINE OIL LEVEL
MEASURING NOW
MEASURE. CORRECT
ONLY IF VEH. LEVELOne of the following messages will
subsequently appear in the indicator:

ENGINE OIL LEVEL
OK


ADD 1.0 Qt. TO
REACH MAX. OIL LEVEL!(Canada:
1.0 LITER
)


ADD 1.5 Qts. TO
REACH MAX. OIL LEVEL!(Canada:
1.5 LITERS
)


ADD 2.0 Qts. TO
REACH MAX. OIL LEVEL!(Canada:
2.0 LITERS
)

If necessary, add engine oil.
For adding engine oil see (
page 243).
For more information on engine oil, see the
“Technical data” section (
page 374) and
(
page 375).iIf you want to interrupt the checking
procedure, press thek orj
button on the multifunction steering
wheel.

241 Operation
Engine compartment
Other display messages
If the SmartKey is not turned to position2
in the starter switch, the following
message will appear:FOR ENGINE OIL LEVEL
SWITCH ON IGNITION!
Switch on the ignition (
page 35).
If you see the message:
OBSERVE WAITING PERIOD
If engine is at operating temperature,
wait five minutes before repeating
check procedure.

If engine is not at operating tempera-
ture yet, wait 30 minutes before re-
peating check procedure.If you see the message:
ENGINE OIL LEVEL
NOT WHEN ENGINE ON!
Turn off the engine.

If the engine is at operating tempera-
ture, wait five minutes before checking
oil.

If the engine is not at operating temper-
ature yet, you must wait 30 minutes
before checking oil.
If there is excess engine oil with the engine
at normal operating temperature, the
following message will appear:
ENGINE OIL LEVEL
REDUCE OIL LEVEL
Have excess oil siphoned or drained
off. Contact an authorized
Mercedes-Benz Light Truck Center.For more information on messages in the
multifunction display concerning engine
oil, see the “Practical hints” section
(
page 296). !Excess oil must be siphoned or drained
off. It could cause damage to the
engine and catalytic converter not
covered by the Mercedes-Benz Limited
Warranty.iPerform the engine oil level check with
the dipstick if it cannot be completed
with the control system (
page 242).
In this case we recommend that you
have the system checked at a
Mercedes-Benz Light Truck Center.

242 OperationEngine compartmentChecking engine oil level with the oil
dipstick
When checking the oil level the vehicle
must

be parked on level ground


be at normal operating temperature


have been stationary for at least five
minutes with the engine turned offTo check the engine oil level with the oil
dipstick, do the following:

Open the hood (
page 238).

Pull out oil dipstick1 (
page 243).

Wipe oil dipstick1 clean.

Fully insert oil dipstick1 into the
dipstick guide tube.

Pull out oil dipstick1 again after
approximately three seconds to obtain
accurate reading.
Oil dipstickThe oil level is correct when it is between
the lower (min) and upper (max) mark of
the oil dipstick.

If necessary, add engine oil.
For adding engine oil see (
page 243).
For more information on engine oil, see the
“Technical data” section (
page 374) and
(
page 375).
For more information on messages in the
multifunction display concerning engine
oil, see the “Practical hints” section
(page 309).
iThe engine oil level can be checked by
either the oil dipstick or via the multi-
function display in the instrument
cluster (
page 240). The amount of
engine oil needed is shown more
precisely in the multifunction display.
iThe filling quantity between the upper
and lower marks on the oil dipstick is
approximately 2.1 US qt. (2.0 l).

243 Operation
Engine compartment
Adding engine oil
Only use approved engine oils and oil fil-
ters required for vehicles with
Maintenance System (U.S. vehicles) or
FSS (Canada vehicles). For a listing of ap-
proved engine oils and oil filters, refer to
the Factory Approved Service Products
pamphlet in your vehicle literature portfo-
lio, or contact an authorized
Mercedes-Benz Light Truck Center.
Using engine oils and oil filters of specifica-
tion other than those expressly required
for the Maintenance System (U.S. vehi-
cles) or FSS (Canada vehicles), or changing
of oil and oil filter at change intervals long-
er than those called for by the
Maintenance System (U.S. vehicles) or
FSS (Canada vehicles) will result in engine
damage not covered by the
Mercedes-Benz Limited Warranty.
G5001Oil dipstick
2Oil filler cap
G55AMG1Oil dipstick
2Oil filler cap
Unscrew oil filler cap2 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.


244 OperationEngine compartment
Screw oil filler cap2 back on filler
neck.
For more information on engine oil, see the
“Technical data” section (
page 374) and
(
page 375).
Transmission fluid level
The transmission fluid level does not need
to be checked. The transmission has a per-
manent supply of automatic transmission
fluid.
If you notice transmission fluid loss or gear
shifting malfunctions, have an authorized
Mercedes-Benz Light Truck Center check
the automatic 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.


the engine must be cool. The coolant
level should reach the COLD LEVEL
mark in the reservoir.
!Excess oil must be siphoned or drained
off. It could cause damage to the
engine and catalytic converter not
covered by the Mercedes-Benz Limited
Warranty.
Warning!
G
In order to avoid any possibly 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 in-
dicates 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
hot fluid and steam will be blown out un-
der 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.