2003 MERCEDES-BENZ G55AMG brake

202 OperationDriving instructionsWinter driving instructions
The most important rule for slippery or icy
roads is to drive sensibly and to avoid
abrupt acceleration, braking and steering
maneuvers. Do not use the cruise control
system under such conditions.
When the vehicle is in danger of skidding,
move selector lever to positionN. Try to
keep the vehicle under control by correc-
tive steering action.Road salts and chemicals can adversely af-
fect braking efficiency. Increased pedal
force may become necessary to produce
the normal brake effect.
We therefore recommend depressing the
brake pedal periodically when traveling at
length on salt-strewn roads.
This can bring road salt impaired braking
efficiency back to normal. Be very careful
that you carry out these braking maneu-
vers without endangering any other road
users.
If the vehicle is parked after being driven
on salt-treated roads, the braking efficien-
cy should be tested as soon as possible af-
ter driving is resumed while observing the
safety rules in the previous paragraph.
For more information on winter driving
(
page 228).
iInformation on driving with snow
chains (
page 229).
Warning!
G
On slippery road surfaces, never downshift
in order to obtain braking action. This could
result in drive wheel slip and reduced vehi-
cle control. Your vehicle’s ABS will not pre-
vent this type of control loss.
Do not engage the transfer case in position
LOW when driving on ice or packed snow. At
speeds below 18 mph (30 km / h) vehicle
steering is adversely affected by the LOW
RANGE – ABS (
page 72).
Warning!
G
If the vehicle becomes stuck in snow, make
sure that snow is kept clear of the exhaust
pipe and from around the vehicle with the
engine running. Otherwise, deadly carbon
monoxide (CO) gases may enter vehicle in-
terior resulting in unconsciousness and
death.
To assure sufficient fresh air ventilation,
open a window slightly on the side of the ve-
hicle not facing the wind.Warning!
G
The outside temperature indicator is not de-
s i g n e d t o s e r v e a s a n i c e - w a r n i n g d e v i c e a n d
is therefore unsuitable for that purpose. In-
dicated temperatures just above the freez-
ing point do not guarantee that the road
surface is free of ice.

204 OperationDriving instructionsRead this chapter carefully before you be-
gin off-road travel.
Familiarize yourself with the vehicle char-
acteristics and gear changing before you
attempt any difficult terrain off-road driv-
ing. We recommend that you start out with
easy off-road travel.Special driving features for off-road
driving
The following driving features are available
for specific kind of operation:


ABS (
page 71)


ESP (
page 75)


4-ETS (
page 74)


Differential lock (
page 145)


Transfer case (
page 141)
Off-road driving rules

Engage the transfer case in position
LOW before driving under off-road con-
ditions (
page 141).

If necessary activate differential locks
(page 145).
The ABS, BAS and ESP are switched off
automatically when the differential
locks are activated.

Fasten items being carried as securely
as possible (
page 173).
Never let the vehicle roll backwards in idle.
You may lose control of the vehicle if you
use only the service brake.
Sand, dirt, mud and other material having
friction property can cause exceptional wear
and tear as well as brake failure.
Have the brakes checked for dirt build-up
and cleaned. There is otherwise a risk that
full braking power may not be available in an
emergency.
iWhenever driving in off-road mode, we
recommend:

Keeping doors, tailgate, windows
and sliding/pop-up roof closed.


Switching cruise control off.
!Observe the following during off-road
driving:

Adjust vehicle speed to condition of
terrain. The more uneven, rutty and
steeper the terrain, the lower the
speed should be. Drive through wa-
ter slowly at an even speed, avoid-
ing a bow wave.


Be especially careful when driving
in unknown territory. It may be nec-
essary to get out of the vehicle and
scout the path you intend to take.


Watch out for obstacles, such as
rocks, holes, tree stumps and ruts.

206 OperationDriving instructionsDriving in steep terrainSlope angle127°
236°

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


Driving on embankments, slopes and
other steep inclines should only be
done straight up or downhill, i.e. in the
line of gravity. Maximum vehicle climb-
ing ability is a 80% grade.


Select gear range2 or1 on the auto-
matic transmission (
page 137).


Drive slowly.


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


Check the brakes after a lengthy down-
grade drive.
Traction in steep terrain
Be easy on the accelerator and watch for
continuous wheel traction when driving in
steep terrain.Driving across a hilltop
Decelerate just ahead of a hilltop (do not
select gear rangeN), to prevent the vehi-
cle from speeding up too much after climb-
ing 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:


jumping across the hilltop


loosing its forward momentum.


speeding up too much after climbing
the hill.
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 the
front axle.The 4-ETS recognizes the sit-
uation and limits the torque for the
front wheels by braking them. Simulta-
neously the torque for the rear wheels
is provided.

207 Operation
Driving instructions
Driving downhill

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


Drive downhill observing the same
rules as driving uphill (
page 206).Driving through water
119 in (48 cm)


Before driving through water, deter-
mine its depth.
It should not be deeper than approxi-
mately 19 in (48 cm).


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


Switch off the exterior lamps as well as
the climate control.


Select gear range2 or1 on the auto-
matic transmission (
page 137).


Enter the water only at a shallow spot,
driving at walking speed.


Do not stop vehicle immersed in water,
and do not shut off the engine.
There is a very high level of driving re-
sistance in water. The surface is slip-
pery and may not be firm, making
pulling away in water difficult and dan-
gerous.


Clean mud off the tire tread after driv-
ing through water.


To dry the brakes, apply pressure to the
brake pedal several times after leaving
the water.
!Only apply the service brake if the vehi-
cle travels 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 vehi-
cle.
!Never accelerate before driving into
the water. The bow wave could force
water into the engine and auxiliary
equipment, thus damaging them.

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.

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).

224 OperationTires and wheels
Tires and wheelsSee your authorized Mercedes-Benz Light
Truck Center for information on tested and
recommended rims and tires for summer
and winter operation. They can also offer
advice concerning tire service and pur-
chase.
Retread tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on
retreads. Mercedes-Benz can therefore
not assure the operating safety of the vehi-
cle when such tires are used.
Important guidelines

Use only 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 pressure loss and damage to
the tire beads.


If vehicle is heavily loaded, check tire
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 under
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 your authorized
Mercedes-Benz Light Truck Center for fur-
ther information. If incorrectly sized rims
and tires are mounted:

The wheel brakes or suspension compo-
nents can be damaged.


The correct operating clearance of the
wheels and the tires are no longer guar-
anteed.
Warning!
G
Do not mix different tire construction types
(i.e. radial, bias, bias-belted) on your vehicle
because handling may be adversely affected
and may result in loss of control.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, use only genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can re-
sult in the bolts loosening and possibly an
accident.

232 OperationVehicle care
Vehicle careCleaning and care of the vehicle
While in operation, even while parked, your
vehicle is subjected to varying external in-
fluences which, if gone unchecked, can at-
tack the paintwork as well as the
underbody and cause lasting damage.
Such damage is caused not only by ex-
treme and varying climatic conditions, but
also by:

Air pollution


Road salt


Tar, gravel and stone chippingTo avoid paint damage, you should imme-
diately remove:


Grease and oil


Fuel


Coolant


Brake fluid


Bird droppings


Insects


Tree resins, etc.
Frequent washing reduces and/or elimi-
nates the aggressiveness and potency of
the above adverse influences.
More frequent washings are necessary to
deal with unfavorable conditions:


Near the ocean


In industrial areas (smoke, exhaust
emissions)


During winter operationYou should check your vehicle from time to
time for stone chipping or other damage.
Any damage should be repaired as soon as
possible to prevent corrosion.
In doing so, do not neglect the underbody
of the vehicle. A prerequisite for a thor-
ough check is a washing of the underbody
followed by a thorough inspection. Dam-
aged areas need to be re-undercoated.
Your vehicle has been treated at the facto-
ry with a wax-base rustproofing in the body
cavities which will last for the lifetime of
the vehicle. Post-production treatment is
neither necessary nor recommended by
Mercedes-Benz because of the possibility
of incompatibility between materials used
in the production process and others ap-
plied later.
We have selected car-care products and
compiled recommendations which are
specially matched to our vehicles and
which always reflect the latest technology.
You can obtain Mercedes-Benz approved
car-care products at your authorized
Mercedes-Benz Light Truck Center.
Warning!
G
Many cleaning products can be hazardous.
Some are poisonous, others are flammable.
Always follow the instructions on the partic-
ular container. Always open your vehicle’s
doors or windows when cleaning the inside.
Never use fluids or solvents that are not de-
signed for cleaning your vehicle.