2007 MERCEDES-BENZ G55AMG service

247 Operation
Driving instructions
Refer to the description of the Brake Assist
System (BAS) (
page 90).
Brake pad wear or a leak in the system may
be the reason for low brake fluid in the
reservoir.
The brake fluid level in the reservoir may
be too low if the brake warning lamp in the
instrument cluster comes on although the
parking brake is released (
page 326).
Observe additional messages in the
multifunction display that may appear
(
page 338).
Have the brake system inspected
immediately. Contact an authorized
Mercedes-Benz Light Truck Center.
All checks and service work on the brake
system should be carried out by qualified
technicians only. Contact an authorized
Mercedes-Benz Light Truck Center.
Only install brake pads and brake fluid
recommended by Mercedes-Benz.After hard braking, it is advisable to drive
on for some time, rather than immediately
park, so the air stream will cool down the
brakes faster.
Driving off
Apply the brakes to test them briefly after
driving off. Perform this procedure only
when the road is clear of other traffic.
Warm up the engine smoothly. Do not
place full load on the engine until the
operating temperature has been reached.
To ensure sufficient traction during
off-road driving, activate differential locks
as needed (
page 175).
Warning!G
If other than recommended brake pads are
installed, or other than recommended brake
fluid is used, the braking properties of the
vehicle can be degraded to an extent that
safe braking is substantially impaired. This
could result in an accident.
!When driving down long and steep grades,
relieve the load on the brakes by shifting into a
lower gear to use the engine’s braking power.
This helps prevent overheating of the brakes and
reduces brake pad wear.
!When driving off on a slippery surface, do
not allow a drive wheel to spin for an extended
period with the ESP
® switched off. Doing so may
cause serious damage to the drivetrain which is
not covered by the Mercedes-Benz Limited
Warranty.
!Simultaneously depressing the accelerator
pedal and applying the brake reduces engine
performance and causes premature brake and
drivetrain wear.

256 Operation
Driving instructions

Driving on embankments, slopes and
other steep inclines should only be
done straight uphill or downhill, i.e. in
the line of gravity. Maximum vehicle
climbing ability is a 80% grade which is
equivalent to a slope angle of approxi-
mately 38 degrees. Keep in mind that
the climbing ability of the vehicle
depends on terrain conditions.

Select gear range2 or1 on the auto-
matic transmission (
page 167).

Drive slowly.

Utilize the engine’s braking power
when descending a slope, observe the
engine speed (do not overrev the
engine). Apply the service brake as
needed.

Check the brakes after a lengthy
downgrade drive.Traction in steep terrain
Be easy on the accelerator and watch for
continuous wheel traction when driving
uphill.
iFor maximum engine speed, see “Instru-
ment cluster” (
page 26) and see “Engine”
(
page 415).
Warning!G
Never turn the vehicle around on steep
inclines. The vehicle might roll over. If the
vehicle cannot complete the attempted
climb, back it down in reverse gear.
iThe 4-ETS helps greatly when starting out on
a steep incline when the front wheels have then
the tendency to slip due to the weight shifting
away from the front axle.
The 4-ETS recognizes the situation and limits the
torque for the front wheels by braking them.
Simultaneously the torque for the rear wheels is
provided.

257 Operation
Driving instructions
Driving across a hilltop
Decelerate just ahead of a hilltop (do not
select gear rangeN), to prevent the
vehicle from speeding up too much after
climbing a hill.
Use the momentum of the vehicle to drive
across the hilltop.
After climbing a hill, driving in this manner
prevents the vehicle from:

loosing ground contact when cresting
hills

loosing its forward momentum

speeding up too much after climbing
the hillDriving downhill

Select gear range1 on the automatic
transmission (
page 167).

Drive downhill observing the same
rules as driving uphill (
page 255).Driving through water
1Fording depth, 19.6 in (50 cm)

Before driving through water,
determine its depth.
!Only apply the service brake if the vehicle is
travelling straight downhill, i.e. in the line of
gravity.
iThe special LOW RANGE – ABS setting
allows for precise and brief (cyclical) blocking of
the front wheels, permitting them to dig into
loose ground.
Remember that, when stopped, the front wheels
slide across a surface and thus lose their ability
to steer the vehicle.
!The water depth must not exceed 19.6 in
(50 cm). The ground under the water might not
be firm which could result the water being
deeper than expected when driving the vehicle
through it. Please note that the water level is
correspondingly lower for flowing water.

261 Operation
Driving instructions

Check tires for possible damage.

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

Check for brush or branches caught in
the underbody.

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.
Driving abroad
Abroad, there is an extensive
Mercedes-Benz service network at your
disposal. If you plan to drive into areas
which are not listed in the index of a
Mercedes-Benz Light Truck Center
directory, you should request pertinent
information from an authorized
Mercedes-Benz Light Truck Center.Control and operation of radio
transmitters
COMAND, radio and telephone*
!Brush or branches could increase the possi-
bility of a fire, as well as cut fuel and/or brake
lines, puncture rubber bellows of the axles or
drive shafts.
Warning!G
Do not forget that your primary responsi-
bility is to drive the vehicle safely. Only
operate the COMAND system, radio or
telephone
1 if road, weather and traffic
conditions permit.
Bear in mind that at a speed of just 30 mph
(approximately 50 km/h), your vehicle is
covering a distance of 44 feet
(approximately 14 m) every second.
1Observe all legal requirements.

263 Operation
Driving instructions
Emission control
Certain engine systems serve to keep the
toxic components of the exhaust gases
within permissible limits required by law.
These systems, of course, will function
properly only when maintained strictly
according to factory specifications. Any
adjustments 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. Moreover, the specified service
jobs must be carried out regularly
according to Mercedes-Benz servicing
requirements. For details refer to the
Maintenance Booklet.
Coolant temperature
During severe operating conditions,
e.g. stop-and-go traffic, the coolant tem-
perature may rise close to approximately
248°F (120°C).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.
Warning!G
Inhalation of exhaust gas is hazardous to
your health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause
unconsciousness and possible 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
window fully open at all times.
iExcessive coolant temperatures trigger a
warning message in the multifunction display
(
page 348).
Warning!G

Driving when your engine is overheated
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 which 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.

265 Operation
At the gas station
Only fill your tank until the filler nozzle
unit cuts out – do not top off or
overfill.
Replace fuel filler cap2 by turning it
clockwise until it audibly engages.
Close fuel filler flap1.
You should hear the latch close shut.
Check regularly and before a long trip
For information on quantities and require-
ments of operating agents, see “Fuels,
coolants, lubricants, etc.” (
page 422).
Open the hood (page 267).
G500
1Coolant
2Brake fluid
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.
!When refueling the vehicle, make certain
that no gasoline comes into contact with the rear
side marker to prevent damaging the lens.
iMake sure to close the fuel filler flap before
locking your vehicle as the flap locking pin
prevents closing after you have locked the
vehicle.
iLeaving the engine running and the fuel cap
open can cause the? malfunction indicator
lamp (USA only) or the± malfunction indica-
tor lamp (Canada only) comes on.
For more information, see “Practical hints”
(
page 328).
iOnly use 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.
Please contact gas station personnel in case la-
bels on the pump cannot be found.
For more information on gasoline, see “Premium
unleaded gasoline” (
page 426), refer to the
Factory Approved Service Products pamphlet
(USA only), or contact an authorized
Mercedes-Benz Light Truck Center.

273 Operation
Engine compartment
Adding engine oil
G500
1Filler cap
G55AMG
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 the
“Technical data” section (
page 423) and
(
page 425).
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.
!Only use approved engine oils and oil filters
required 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 (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 (U.S. vehicles) 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 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 not covered by the
Mercedes-Benz Limited Warranty.

277 Operation
Tires and wheels
Tires and wheels
Contact an authorized Mercedes-Benz
Light Truck Center for information on test-
ed and recommended rims and tires for
summer and winter operation. They can
also offer advice concerning tire service
and purchase.Important guidelines

Only use sets of tires and rims of the
same type and make.

Tires must be of the correct size for the
rim.

Break in new tires for approximately
60 miles (100 km) at moderate
speeds.

Regularly check the tires and rims for
damage. Dented or bent rims can
cause tire inflation pressure loss and
damage to the tire beads.

If vehicle is heavily loaded, check tire
inflation pressure and correct as
required.

Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths of less than
1/8in (3 mm).

When replacing individual tires, you
should mount new tires on the front
wheels first (on vehicles with
same-sized wheels all around).
Warning!G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. See an authorized
Mercedes-Benz Light Truck Center for fur-
ther information. If incorrectly sized rims
and tires are mounted:

The wheel brakes or suspension
components can be damaged.

The operating clearance of the wheels
and the tires may no longer be correct.
Warning!G
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can
result in the bolts loosening and possibly an
accident.
Retreaded tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on
retreads. The operating safety of the vehicle
cannot be assured when such tires are used.