2003 MERCEDES-BENZ G55AMG coolant temperature

220 OperationEngine compartmentAdding engine oil
Unscrew cap2 from the filler neck.

Add oil. Be careful not to overfill with
oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
coming into contact with the ground or wa-
ter.

Screw cap2 back on the filler neck.
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.
!Excessive 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.
The oil dipstick1 tube allows for drain-
ing of oil by using a suction device.
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 engine temperature is above
194°F (90°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.

251 Practical hints
What to do if …
Display
Possible cause
Suggested solution
Category
B
COOLANT
CHECK LEVEL!
The coolant level is too low.

Add coolant (
page 220).

If you have to add coolant fre-
quently, have the cooling sys-
tem checked by an authorized
Mercedes-Benz Light Truck
Center.
2
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 can 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 108).

252 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
Possible cause
Suggested solution
Category
B
COOLANT
STOP, ENGINE OFF!
The coolant is too hot.

Stop the vehicle and turn off
the engine.

Only start the engine again af-
ter the message disappears.
You could otherwise damage
the engine.
1
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 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 it
cools 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.

267 Practical hints
What to do if …
G
VISIT WORKSHOP!
DISPLAY FAULTY
The instrument cluster display is
malfunctioning.
Some systems themselves may also
have failed.

Continue driving with added
caution.

Visit an authorized Mer-
cedes-Benz Light Truck Center
as soon as possible.
2
±
VISIT WORKSHOP!
DISPLAY FAULTY
Certain electronic systems are un-
able to relay information to the con-
trol 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.
2
W
WASHER FLUID
CHECK LEVEL!
The fluid level has dropped to about 1/3 of total reservoir capacity.

Add washer fluid
(page 321).
3
Display
Possible cause
Suggested solution
Category

316 Technical dataFuels, coolants, lubricants etc.
Fuels, coolants, lubricants etc.Capacities
Vehicle components and their respective
lubricants must match.Therefore use only brands tested and rec-
ommended by Mercedes-Benz.Please refer to the Factory Approved Ser-
vice Products pamphlet, or inquire at your
Mercedes-Benz Light Truck Center.
Model
Capacity
Fuels, coolants, lubricants etc.
Engine with oil filter
G500
G55AMG
8.5 US qt (8.0 l)
8.0 US qt (7.5 l)
Recommended engine oils
Automatic transmission
9.0 US qt (8.5 l)
MB Automatic Transmission Fluid
1
1MB part no. 001 989 21 03 10Transfer 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
1.5 US qt (1.4 l)
Hypoid gear oil SAE 90, 85 W 90
Rear axle
1.9 US qt (1.8 l)
Hypoid gear oil SAE 90, 85 W 90
Power steering
approx. 1.06 US qt (1.0 l)
MB Power Steering Fluid, or
approved Dextron III ATF
Front wheel hubs
approx. 1.5 oz (43 g) each
High temperature roller bearing grease
Brake system
approx. 0.53 US qt (0.5 l)
MB Brake Fluid (DOT 4+)
Fuel tank
including a reserve of
25.4 US gal (96.0 l)
5.3 US gal (20.0 l)
Premium unleaded gasoline:
Posted Octane 91
(average of 96 RON / 86 MON)

317 Technical data
Fuels, coolants, lubricants etc.
Engine oils
Engine oils are specifically tested for their
suitability in our engines. Therefore, use
only engine oils recommended by
Mercedes-Benz. Information on recom-
mended brands is available in the Factory
Approved Service Products pamphlet, or at
your authorized Mercedes-Benz Light
Truck Center.
Please follow FSS and Service Booklet rec-
ommendations for scheduled oil changes.
F ai lu re to d o s o could res ul t in engi ne da m -
age not covered by the Mercedes-Benz
Limited Warranty.
Engine oil additives
Do not blend oil additives with engine oil.
They may be harmful to the engine opera-
tion.
Damage or malfunctions resulting from
blending oil additives are not covered by
the Mercedes-Benz Limited Warranty.
Air conditioning refrigerant
R-134a (HFC) refrigerant and special PAG
lubricating oil is used in the air condition-
ing system.
Never use R-12 (CFC) or mineral-based lu-
bricating oil, otherwise damage to the
system will occur.
Model
Capacity
Fuels, coolants, lubricants etc.
Cooling system
approx. 12.7 US qt (12.0 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 or MB Windshield Washer Concentrate “S” and commercially available pre-
mixed windshield washer solvent / antifreeze for temperatures below freezing. Follow suggested mixing ratios (
page 321).

319 Technical data
Fuels, coolants, lubricants etc.
Gasoline additives
A major concern among engine manufac-
turers is carbon build-up caused by gaso-
line. Mercedes-Benz recommends only the
use of quality gasoline containing additives
that prevent the build up of carbon depos-
its.
After an extended period of using fuels
without such additives, carbon deposits
can build up especially on the intake valves
and in the combustion area, leading to en-
gine performance problems such as:

Warm-up hesitation


Unstable idle


Knocking/pinging


Misfire


Power loss
Do not blend other specific fuel additives
with fuel. This only results in unnecessary
cost and may be harmful to the engine op-
eration.Damage or malfunctions resulting from
poor fuel quality or from blending specific
fuel additives are not covered by the
Mercedes-Benz Limited Warranty.
Coolants
The engine coolant is a mixture of water
and anticorrosion / antifreeze, which pro-
vides:

Corrosion protection


Freeze protection


Boiling protection (by increasing the
boiling point)
The cooling system was filled at the factory
with a coolant providing freeze protection
to approximately -35°F (-37°C) and corro-
sion protection.
If the antifreeze mixture is effective to
-22°F (-30°C), the boiling point of the cool-
ant in the pressurized cooling system is
reached at approximately 266°F (130°C).The coolant solution must be used year
round to provide the necessary corrosion
protection and increase in the boil-over
protection. You should have it replaced
every 3 years.
To provide important corrosion protection,
the solution must be at least 45% anticor-
rosion/antifreeze (equivalent to freeze
protection to approx. - 22°F [-30°C]).
If you use a solution that is more than 55%
anticorrosion/antifreeze (freeze protec-
tion to approx. - 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
anticorrosion /antifreeze should be used
to bring it up to the proper level (have cool-
ing system checked for signs of leakage).
Please make sure that the mixture is in ac-
cordance with label instructions.
The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water. If you

321 Technical data
Fuels, coolants, lubricants etc.
Windshield/rear window washer sys-tem and headlamp cleaning system
The windshield washer reservoir is located
in the engine compartment on the front
passenger side. It holds approximately 5.3
US qt (5.0 l). The headlamp cleaning sys-
tem is also supplied from the windshield
washer reservoir. 
Refill the reservoir with MB Windshield
Washer Concentrate “S” to and water
(or concentrate and commercially
available premixed windshield washer
solvent / antifreeze, depending on am-
bient temperatures) (
page 321).Washer fluid mixing ratio
For temperatures above freezing use
MB Windshield Washer Concentrate “S”
and water:


1 part “S” to 100 parts water
[40 ml “S” to 1 gallon (4 liters) water]
For temperatures below freezing use
MB Windshield Washer Concentrate “S”
and commercially available premixed
windshield washer solvent / antifreeze:


1 part “S” to 100 parts solvent
[40 ml “S” to 1 gallon (4 liters) solvent]
Warning!
G
Washer solvent/antifreeze is highly flamma-
ble. Do not spill washer solvent/antifreeze
on hot engine parts, because it may burn.
You can be seriously burned.