2003 MERCEDES-BENZ G55AMG Owner's Manual

209 Operation
Driving instructions
Ruts


Check the vehicle clearance before
driving in ruts.


Comply with the warnings
(page 203) and rules for off-road
driving (
page 204).


Select gear range1 on the automatic
transmission (
page 137).


Drive slowly next to the ruts rather than
through them if at all possible.Returning from off-road driving
!A number of off-road tracks or other by-
roads have deep ruts. If the vehicle
does not have enough ground clear-
ance:

it could be damaged


the underside of the vehicle may
come down on a surface and re-
main stuck
After off-road driving or crossing obsta-
cles, inspect vehicle for any damage,
especially vehicle undercarriage and
suspension components. Failure to do
so can adversely affect the vehicle's fu-
ture performance, including increased
chance of an accident.
Warning!
G
Never drive on pavement with activated dif-
ferential locks. Engaged front axle differen-
tial locks limits ability to move around
curves.
If you feel a sudden significant vibration or
ride disturbance, or you suspect that possi-
ble damage to your vehicle has occurred,
you should turn on the hazard warning flash-
ers, carefully slow down, and drive with cau-
ti o n to a n a r ea wh ic h i s a s a fe dis t an c e f ro m
the roadway.
Inspect the tires and under the vehicle for
possible damage. If the vehicle or tires ap-
pear unsafe, have it towed to the nearest
Mercedes-Benz Light Truck Center or tire
dealer for repairs.
Damage to the vehicle negatively influences
driving comfort and poses the risk of acci-
dent to you and other drivers.

210 OperationDriving instructionsOff-road driving increases strain on the ve-
hicle.
We recommend that you inspect the vehi-
cle for possible damage after each off-road
trip. Recognizing any damage and a subse-
quent timely repair reduces the chance of
a possible breakdown or accident later on.
Proceed as follows:

Switch the transfer case in position
HIGH (
page 141).


Disengage differential locks
(page 146).


Remove excessive dirt from tires,
wheels, wheel housings, and under-
body.
For instance, after driving in mud, clean
the radiator, chassis, engine, brakes,
and wheels from extreme dirt using a
strong jet of water.


Inspect frame, oil pan, brake hoses,
etc., as well as vehicle underbody for
possible damage.


Check tires for possible damage and
remove foreign objects. Clean all exte-
rior lamps and conduct a brake test.


Clean all exterior lamps and check
them for possible damage.


Check for brush or branches caught in
the undercarriage.
They could increase the possibility of a
fire, as well as cut fuel and/or brake
lines, puncture rubber bellows of the
axles or drive shafts.


After continued operation in mud,
sand, water or other dirty conditions,
clean the brake discs, wheels, brake
pads and check and clean axle joints.


Conduct a brake test.Control and operation of radio trans-
mitters
COMAND, radio and telephone*Warning!
G
Do not forget that your primary responsibili-
ty is to drive the vehicle safely. Only operate
the COMAND, radio or telephone
1 if road,
traffic and weather conditions permit.
Bear in mind that at a speed of just 30 mph
(approximately 50 km / h), your vehicle is
covering a distance of approximately
50 feet (approximately 14 m) every second.
1Observe all legal requirements.

211 Operation
Driving instructions
Telephones and two-way radios
Radio transmitters, such as a portable tele-
phone or a citizens band unit should only
be used inside the vehicle if they are con-
nected to an antenna that is installed on
the outside of the vehicle.
Refer to the radio transmitter operation in-
structions regarding use of an external an-
tenna.
Driving abroad
Abroad, there is a widely-spread
Mercedes-Benz service network at your
disposal. If you plan to drive into areas
which are not listed in the index of your
Mercedes-Benz Light Truck Center directo-
ry, you should request pertinent informa-
tion from your authorized Mercedes-Benz
Light Truck Center.Catalytic converter
Your Mercedes-Benz is equipped with
monolithic type catalytic converters, an
important element in conjunction with the
oxygen sensors to achieve substantial con-
trol of the pollutants in the exhaust emis-
sions. Keep your vehicle in proper
operating condition by following our rec-
ommended maintenance instructions as
outlined in your Service Booklet.
Warning!
G
Never operate radio transmitters equipped
with a built-in or attached antenna (i.e. with-
out being connected to an external antenna)
from inside the vehicle while the engine is
running. Doing so could lead to a malfunc-
tion of the vehicle’s electronic system, pos-
sibly resulting in an accident and/or
personal injury.
!To prevent damage to the catalytic con-
verters, use only premium unleaded
gasoline in this vehicle.
Any noticeable irregularities in engine
operation should be repaired promptly.
Otherwise, excessive unburned fuel
may reach the catalytic converter,
causing it to overheat and start a fire.Warning!
G
As with any vehicle, do not idle, park or op-
erate this vehicle in areas where combusti-
ble materials such as grass, hay or leaves
can come into contact with the hot exhaust
system, as these materials could be ignited
and cause a vehicle fire.

212 OperationDriving instructionsEmission control
Certain engine systems serve to keep the
toxic components of the exhaust gases
within permissible legal limits.
These systems, of course, will function
properly only when maintained strictly ac-
cording to factory specifications. Any ad-
justments on the engine should, therefore,
be carried out only by qualified
Mercedes-Benz Light Truck Center autho-
rized technicians. Engine adjustments
should not be altered in any way. More-
over, the specified service jobs must be
carried out regularly according to
Mercedes-Benz servicing requirements.
For details refer to the Service Booklet.
Coolant temperature
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise to approx. 248°F
(120°C).
The engine should not be operated with
the coolant temperature above 248°F
(120°C). Doing so may cause serious en-
gine damage which is not covered by the
Mercedes-Benz Limited Warranty.
Warning!
G
Inhalation of exhaust gas is hazardous to
your health. All exhaust gas contains carbon
monoxide, and inhaling it can cause uncon-
sciousness and lead to death.
Do not run the engine in confined areas
(such as a garage) which are not properly
ventilated. If you think that exhaust gas
fumes are entering the vehicle while driving,
have the cause determined and corrected
immediately. If you must drive under these
conditions, drive only with at least one win-
dow fully open at all times.
iExcessive coolant temperatures trigger
a warning message in the multifunction
display (
page 252).

213 Operation
Driving instructions
Warning!
G


Driving when your engine is badly over-
heated can cause some fluids which
may have leaked into the engine com-
partment to catch fire. You could be se-
riously burned


Steam from an overheated engine can
cause serious burns and can occur just
by opening the engine hood. Stay away
f r o m t h e e n g i n e i f y o u s e e o r h e a r s t e a m
coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until it
cools down.

214 OperationAt the gas station
At the gas stationThe fuel filler flap is located on the
right-hand side of the vehicle towards the
rear. Locking/unlocking the vehicle with
the remote control automatically
locks/unlocks the fuel filler flap.

Turn off the engine.

Remove the key from the starter
switch.

Open the fuel filler flap by pushing at
the point indicated by the arrow.

Turn the fuel cap to the left and hold on
to it until possible pressure is released.

Take off the cap and set it in the recess
on the fuel filler flap.

To prevent fuel vapors from escaping
into open air, fully insert filler nozzle
unit.

Only fill your tank until the filler nozzle
unit cuts out – do not top up or overfill.

Replace the fuel cap by turning it to the
right.
You should hear the fuel filler cap en-
gage.

Close the fuel filler flap.
Warning!
G
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious inju-
ry. Whenever you are around gasoline, avoid
inhaling fumes and skin contact, extinguish
all smoking materials. Never allow sparks,
flame or smoking materials near gasoline!
Failure to remove the fuel cap slowly could
result in personal injury.
Warning!
G
Overfilling of the fuel tank may create pres-
sure in the system which could cause a gas
discharge. This could cause the gas to spray
back out when removing the fuel pump noz-
zle, which could cause personal injury.!The fuel filler cap is tethered to the fuel
f i l l e r n e c k . D o n o t d r o p t h e c a p . I t c o u l d
damage the vehicle paint finish.
When refueling the vehicle, make cer-
tain that no gasoline comes into con-
tact with plastic tail lamp to prevent
damaging the lens.

215 Operation
At the gas station
Check regularly and before a long trip
1Coolant
2Brake fluid
Coolant
For normal replenishing, use water (pota-
ble water quality). For more information on
coolant level see (
page 220) and the
“Technical data” section (
page 316).
Brake fluid
More information on brake fluid can be
found in the “Technical data” section
(
page 316).Windshield/rear window washer sys-
tem and headlamp cleaning system
For more information on refilling the reser-
voir, see (
page 222).
Engine oil level
For more information on engine oil, see
(
page 218).
Vehicle lighting
Check function and cleanliness. More in-
formation on replacing light bulbs can be
found in the “Practical hints” section
(page 279).
Exterior lamp switch (
page 100).
Tire inflation pressure
For more information on tire inflation pres-
sure, see (
page 225).
iUse only premium unleaded gasoline
with a minimum Posted Octane Rating
of 91 (average of 96 RON / 86 MON).
Information on gasoline quality can
normally be found on the fuel pump.
More information on gasoline can be
found in the Factory Approved Service
Products pamphlet. iLeaving the engine running and the fuel
cap open can cause the
?
lamp to
illuminate.
See also “Practical hints” section
(
page 243).
iOpening the hood, see (
page 216).

216 OperationEngine compartment
Engine 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 arrow
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. If necessary,
call the fire department.