2007 MERCEDES-BENZ GL450 Oil engine

379 Operation
Engine compartment
Engine compartment
Hood
Opening
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.
This could cause the hood to come loose
and injure you and/or others.
Warning!G
If you see flames or smoke coming from the
engine compartment, or if the coolant tem-
perature gauge 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. If necessary,
call the fire department.
Warning!G
You could be injured when the hood is open
– even when the engine is turned off.
Parts of the engine can become very hot. To
prevent burns, let the engine cool off com-
pletely before touching any components on
the vehicle. Comply with all relevant safety
precautions.
Warning!G
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.
Warning!G
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, diagnos-
tic 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
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)


381 Operation
Engine compartment
Engine oil
The amount of oil your engine needs will
depend on a number of factors, including
driving style. Increased 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.Checking engine oil level with the oil
dipstick
When checking the oil level

the vehicle must be parked on level
ground

the vehicle must have been stationary
for at least 5 minutes with the engine
turned off
Example GL 450 (GL 320 CDI similar)
1Oil dipstick
2Upper mark
3Lower mark
Open the hood (page 379).
Pull out oil dipstick1.
Wipe oil dipstick1 clean.
Fully insert oil dipstick1 into the
dipstick guide tube.
Pull out oil dipstick1 again after
approximately 3 seconds to obtain
accurate reading.
The oil level is correct when it is be-
tween lower mark3 (min.) and upper
mark2 (max.) of the oil dipstick.
If necessary, add engine oil
(
page 382).
For more information on engine oil, see
“Technical data” section (
page 560) and
(
page 562).
iDo 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.
More information on this subject is available at
any Mercedes-Benz Light Truck Center.
iThe filling quantity between the upper and
lower marks on the oil dipstick is approximately
2.1 US qt. (2.0 l).

382 Operation
Engine compartment
Adding engine oil
Example GL 450 (GL 320 CDI similar)
1Filler cap
Unscrew filler cap1 from filler neck.
Add engine oil as required. Never over-
fill 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
“Technical data” section (
page 560) and
(
page 562).
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.
!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) in your vehicle
literature portfolio, or contact an authorized
Mercedes-Benz Light Truck Center.
Using engine oils and oil filters of specification
other than those expressly required for the
Maintenance 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 could cause damage to the engine and/or
catalytic converter (gasoline engine) or the oxi-
dation catalyst (diesel engine) not covered by
the Mercedes-Benz Limited Warranty.

424 Operation
Maintenance
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 (page 42).
Press buttonè orÿ on the mul-
tifunction steering wheel repeatedly
until the standard display appears in
the multifunction display (
page 164).
Press buttonk orj until the
maintenance service indicator display
with the service symbol9 and the
service deadline appears in the multi-
function display.Resetting the maintenance service
indicator
In the event that the maintenance service
on your vehicle is not carried out by an
authorized Mercedes-Benz Light Truck
Center, you can have the maintenance
service indicator reset. The automotive
maintenance facility carrying out the
maintenance service will find the informa-
tion for resetting the maintenance service
indicator in the maintenance-relevant
information for your vehicle. Such informa-
tion is available from either your
authorized Mercedes-Benz Light Truck
Center or directly from Mercedes-Benz.
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 dead-
line, you will need to subtract these days from
the days shown in the maintenance service indi-
cator message or maintenance service indicator
display.
Do not confuse the maintenance service indica-
tor with the engine oil level indicatorN.
!If the maintenance service indicator was
inadvertently reset, have an authorized
Mercedes-Benz Light Truck 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.

476 Practical hints
What to do if …
When the message Add 1 qt. engine oil
at next refueling
(Canada: 1 liter)
appears while the engine is running and at
operating temperature, the engine oil level
has dropped to approximately the mini-
mum level.
When this occurs, the warning will first
come on intermittently and then stay on if
the oil level drops further.Visually check for oil leaks. If no obvious oil
leaks are noted, drive to the nearest
service station where the engine oil should
be topped to the required level with an
approved oil.
For information on approved engine oils,
refer to the Factory Approved Service
Products pamphlet (USA only) or contact
an authorized Mercedes-Benz Light Truck
Center.
Display symbolDisplay messagesPossible cause/consequencePossible solution
NCheck eng. oil level
at next refuelingThe engine oil level is too low.Check the engine oil level (page 381).
USA only:
Add 1 qt. engine oil
at next refueling
Canada only:
Add 1 liter engine oil
at next refueling
The engine oil level is too low.Add engine oil (page 382) and check
the engine oil level (
page 381).
Engine oil level
cannot be measuredThe measuring system is
malfunctioning.Have the measuring system checked by
an authorized Mercedes-Benz Light Truck
Center.

477 Practical hints
What to do if …
Display symbolDisplay messagesPossible cause/conse-
quencePossible solution
NEngine oil level
Stop car, turn engine offThere is no oil in the engine.
There is a danger of engine
damage.Carefully bring the vehicle to a halt as soon as it
is safe to do so in a safe location.
Turn off the engine.
Add engine oil (page 382) and check the en-
gine oil level (
page 381).
Engine oil level
Reduce oil levelYou have added too much
engine oil. There is a risk of
damaging the engine and/or
the catalytic converter (gaso-
line engine) or the oxidation
catalyst (diesel engine).Have oil siphoned or drained off.
Observe all legal requirements with respect to
its disposal.
Engine oil level
Visit workshopThe engine oil has dropped to
a critical level.Check the engine oil level (page 381) and add
oil as required (
page 382).
If you must add engine oil frequently, have the
engine checked for possible leaks.
!The engine oil level warnings should not be
ignored. Extended driving with the symbol dis-
played could result in serious engine damagethat is not covered by the Mercedes-Benz
Limited Warranty.

560 Technical data
Fuels, coolants, lubricants
Capacities
Vehicle components and their respective
lubricants must match. Therefore only use
products tested and approved by
Mercerdes-Benz.
Please refer to the Factory Approved
Service Products pamphlet (USA only), or
inquire at an authorized Mercedes-Benz
Light Truck Center.
Warning!G
Comply with all valid regulations with re-
spect to handling, storing and disposing of
service fluids. Otherwise you could
endanger persons or the environment.
Keep service fluids out of the reach of
children.
For health reasons, you should prevent
service fluids from coming into direct
contact with your skin or clothing.
If a service fluid is swallowed, contact a
physician immediately.
ModelCapacityFuels, coolants, lubricants, etc.
Engine with oil filterAll models9.0 US qt (8.5 l)Approved engine oils
Automatic transmissionAll models9.5 US qt (9.0 l)MB Automatic Transmission Fluid
Transfer case single speedAll models0.5 US qt (0.5 l)MB Automatic Transmission Fluid
Transfer case double speed*All models1.6 US qt (1.5 l)MB Automatic Transmission Fluid
Front axleAll models1.2 US qt (1.1 l)Hypoid gear oil
Rear axleAll models1.2 US qt (1.1 l)Hypoid gear oil
Rear axle with differential lock*All models1.7 US qt (1.6 l)Hypoid gear oil

561 Technical data
Fuels, coolants, lubricants
ModelCapacityFuels, coolants, lubricants, etc.
Power steeringAll modelsapprox. 1.3 US qt (1.2 l)MB Power Steering Fluid or approved
Dexron III ATF
Front wheel hubsAll modelsapprox. 1.5 oz (43 g) eachHigh temperature roller bearing grease
Brake systemAll models-MB Brake Fluid (DOT 4+)
Cooling systemGL 320 CDIapprox. 10.0 US qt (9.5 l)MB Anticorrosion/Antifreeze
GL 450approx. 10.6 US qt (10.0 l)MB Anticorrosion/Antifreeze
Fuel Tank
including a reserve ofAll models26.4 US gal (100.0 l)
approx. 3.4 US gal (13.0 l)Gasoline engine:
Premium unleaded gasoline:
Minimum Posted Octane 91
(Avg. of 96 RON/86 MON)
Diesel engine:
ULTRA-LOW SULFUR DIESEL FUEL
(15 ppm SULFUR MAXIMUM)
Air conditioning systemAll models-R-134a refrigerant and special PAG lubricant oil
(never R-12)
Windshield washer system
and headlamp cleaning
system*All models8.1 US qt (7.7 l)MB Windshield Washer Concentrate1
1Use MB Windshield Washer Concentrate “MB SummerFit” and water for temperatures above freezing or MB Windshield Washer Concentrate “MB SummerFit” and
commercially available premixed windshield washer solvent/antifreeze for temperatures below freezing. Follow suggested mixing ratios (page 567).