2005 MERCEDES-BENZ G55AMG coolant temperature

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.


305 Practical hints
What to do if …
Display symbol
Display message
Possible cause
Possible solution
B
COOLANT
CHECK LEVEL!
The coolant level is too low.

Add coolant (
page 244).

If you have to add coolant frequently,
have the cooling system checked by
an authorized Mercedes-Benz Light
Truck Center.
Warning!
G
Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. You could be seriously burned.
!Do not ignore the low engine coolant
level warning. Extended driving with
the message and symbol displayed
may cause serious engine damage not
covered by the Mercedes-Benz Limited
Warranty.
Do not drive without sufficient amount
of coolant in the cooling system. The
engine will overheat causing serious
engine damage.
Observe the coolant temperature dis-
play (
page 120).

306 Practical hintsWhat to do if …
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 248°F (120°C).
Display symbol
Display message
Possible cause
Possible solution
Ï
COOLANT
STOP, ENGINE OFF!
The coolant is too hot.

Stop the vehicle and turn off the en-
gine.

Only start the engine again after the
message disappears. You could other-
wise damage the engine.
Warning!
G
Driving when your engine is badly overheat-
ed 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 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
engine damage which is not covered by
the Mercedes-Benz Limited Warranty.

307 Practical hints
What to do if …
Display symbol
Display message
Possible cause
Possible solution
Ï
COOLANT
STOP, ENGINE OFF!
The poly-V-belt could be broken.

Stop immediately and check the
poly-V-belt.
If it is broken:

Do not continue to drive. Otherwise
the engine will overheat due to an
inoperative water pump which may re-
sult in damage to the engine. Notify an
authorized Mercedes-Benz Light Truck
Center.
If it is in order:

Do not continue to drive the vehicle
with this message displayed. Doing so
could result in serious engine damage
that is not covered by the
Mercedes-Benz Limited Warranty.

Observe the coolant temperature
display (
page 120).

Drive immediately to the nearest au-
thorized Mercedes-Benz Light Truck
Center.

308 Practical hintsWhat to do if …Ï
COOLANT
VISIT WORKSHOP!
The cooling fan for the coolant is
malfunctioning.

Observe the coolant temperature dis-
play (
page 120).

Have the fan replaced as soon as pos-
sible.
Ñ
CRUISE CONTROL
VISIT WORKSHOP!
Cruise control is malfunctioning.

Visit an authorized Mercedes-Benz
Light Truck Center.
J
DOOR OPEN!
You are attempting to drive with one ore
more doors open.

Close the doors.
e
ENGINE AIR FILTER
VISIT WORKSHOP!
The engine air filter is clogged and must
be replaced.

Visit an authorized Mercedes-Benz
Light Truck Center as soon as possi-
ble.
Display symbol
Display message
Possible cause
Possible solution

320 Practical hintsWhat to do if …Display
Possible cause
Possible solution
Ê
TRUNK OPEN!
This message will appear whenever the
tailgate is open.

Close the tailgate.
G
VISIT WORKSHOP!
DISPLAY MALFUNCTION:
The instrument cluster display is malfunc-
tioning.
Some systems themselves may also have
failed.

Continue driving with added caution.

Visit an authorized Mercedes-Benz
Light Truck Center as soon as
possible.
±
VISIT WORKSHOP!
DISPLAY MALFUNCTION:
Certain electronic systems are unable to
relay information to the control system.
The following systems may have failed:

Coolant temperature display


Tachometer


Cruise control display

Have the electronic systems checked
by an authorized Mercedes-Benz Light
Truck Center.
W
WASHER FLUID
CHECK LEVEL!
The fluid level has dropped to about
1/3
of total reservoir capacity.
Add washer fluid (
page 380).

374 Technical dataFuels, coolants, lubricants, etc.Capacities
Vehicle components and their respective
lubricants must match.Therefore use only products tested and ap-
proved by Mercedes-Benz.Please refer to the Factory Approved Ser-
vice Products pamphlet, or inquire at an
Mercedes-Benz Light Truck Center.
Model
Capacity
Fuels, coolants, lubricants, etc.
Engine with oil filter
G 500
G55AMG
8.5 US qt (8.0 l)
9.0 US qt (8.5 l)
Approved engine oils
Automatic transmission
9.0 US qt (8.5 l)
MB Automatic Transmission Fluid
Transfer case
2.96 US qt (2.8 l)
MB part no. A 001 989 28 03 10
Differential lock mechanism
0.47 - 0.63 US qt
(0.45 - 0.6 l)
Brake fluid DOT 3+4, SAE J1703
Front axle
G 500
G55AMG
1.5 US qt (1.4 l)
1.5 US qt (1.4 l)
Hypoid gear oil SAE 85W-90
Hypoid gear oil Castrol SAF-XJ
Rear axle
G 500
G55AMG
1.9 US qt (1.8 l)
1.9 US qt (1.8 l)
Hypoid gear oil SAE 85W-90
Hypoid gear oil Castrol SAF-XJ
Power steering
approx. 1.06 US qt (1.0 l)
MB Power Steering Fluid, or
approved Dexron III ATF
Front wheel hubs
approx. 1.5 oz (43 g) each
High temperature roller bearing grease
Fuel tank
including a reserve of
G 500
G55AMG
25.4 US gal (96.0 l)
23.8 US gal (90.0 l)
3.4 US gal (13.0 l)
Premium unleaded gasoline:
Minimum Posted Octane 91
(average of 96 RON / 86 MON)

375 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 re-
quired for vehicles with Maintenance
System (U.S. vehicles) or FSS (Canada
vehicles). For a listing of approved engine
oils and oil filters, refer to the Factory
Approved Service Products pamphlet, 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
longer 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.Please follow Maintenance System (U.S.
vehicles) or FSS (Canada vehicles) recom-
mendations for scheduled oil changes.
Failure to do so will result in engine dam-
age not covered by the Mercedes-Benz
Limited Warranty.
Model
Capacity
Fuels, coolants, lubricants, etc.
Cooling system
G 500
G55AMG
approx. 12.7 US qt (12.0 l)
approx. 13.4 US qt (12.7 l)
MB Anticorrosion/Antifreeze
Air conditioning system
R-134a refrigerant and
special PAG lubricant oil (never R-12)
Windshield/rear window washer system
and headlamp cleaning system
approx. 7.9 US qt (7.5 l)
MB Windshield Washer Concentrate
and water
1
1Use MB Windshield Washer Concentrate “S” and water for temperatures above freezing point or MB Windshield Washer Concentrate “S” and commercially available
premixed windshield washer solvent / antifreeze for temperatures below freezing point. Follow suggested mixing ratios (page 380).