2004 MERCEDES-BENZ G55AMG ABS

141 Controls in detail
Automatic transmission
One-touch gearshifting
Even with an automatic transmission, you
can change the gears manually when the
gear selector lever is in positionD.
Downshifting
Briefly press the gear selector lever to
the left in the D–direction.
The transmission will shift from the current
gear to the next lower gear. This action si-
multaneously limits the gear range of the
transmission (
page 142).Upshifting

Briefly press the gear selector lever to
the right in the D+direction.
The transmission will shift from the current
gear to the next higher gear as permitted
by the shift program. This action simulta-
neously extends the gear range of the
transmission.Canceling gear range limit

Press and hold the gear selector lever
in the D+direction until
Dreappears in
the multifunction display.
The transmission will shift from the current
gear range directly to gear rangeD.
Shifting into optimal gear range

Press and hold the gear selector lever
in the D-direction.
The transmission will automatically select
the gear range suited for optimal accelera-
tion and deceleration. This will involve
shifting down one or more gears.
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 loss of control.
iTo avoid overrevving the engine when
the gear selector lever is moved to the
D- direction, the transmission will not
shift to a lower gear if the engine’s
max. speed would be exceeded.

148 Controls in detailDifferential locks
Differential locksFor more information on off-road driving,
see “Off-road driving” (
page 213).
Differential locks improve the vehicle’s
tractive power off-road. Switch on differen-
tial locks:


for off-road driving


to turn the ABS off during off-road driv-
ing


for driving through water


when driving on deep snow and icy or
fouled surfaces!Do not engage the front axle differen-
tial lock when driving around tight cor-
ners. This restricts steering ability.
!When driving off-road, apply only mod-
erate pressure to the accelerator pedal
if the differential locks are switched on.
When running on a (single-axle) dyna-
mometer – no matter how briefly – you
must:

raise the non-driven axle
or


disconnect its drive shaft
and


engage the transfer differential lock
Otherwise the transfer case can be
damaged, which is not covered by the
Mercedes-Benz Limited Warranty.
Warning!
G
Never drive on pavement with differential
locks engaged.
Steering control will be strongly affected
with the differential locks activated.
The ABS, BAS and ESP are switched off au-
tomatically when the transfer case differen-
tial lock is activated.

149 Controls in detail
Differential locks
A few words about differentials and differential locks
When a vehicle negotiates a turn, wheels
on the outside of the curve must travel far-
ther and rotate faster than the inside
wheels. The differential, the operation of a
set of gears that allows the powered
wheels in a vehicle to turn at different
speeds, makes this essential function pos-
sible.
The drawback is that the differential also
sends most of the engine’s power to the
wheel with the least load or strain on it. For
example, if one of a vehicle’s powered
wheels sits on a patch of snow and spins
because there is no traction, all of the en-
gine’s power will go to that wheel because
the power will take the path of least resis-
tance. Meanwhile, the opposite wheel, sit-
ting on dry pavement where it could get
enough grip to start the vehicle moving,
sits idle because it receives no power.The Electronic Traction System (ETS) ad-
dresses this problem and provides for
good control and steering ability by auto-
matically slowing the slipping wheel and
thus increasing the power to the other
non-slipping drive wheels to get the vehicle
moving. The ESP and ETS in this vehicle
feature such intelligent limited-slip differ-
ential technology, ideally suited for
on-road and light off-road driving. Transfer
case position LOW (
page 145) also en-
hances off-road driving capabilities
(
page 213).
More extreme off-road conditions may call
for another solution, engaging a differen-
tial lock or preventing the differential from
operating altogether. As part of its stan-
dard equipment, this vehicle comes with
three differential locks: front, transfer case
(center) and rear. Each can be engaged
simply by pushing dashboard-mounted
buttons in sequential order (center, rear,
front) (
page 150). When the transfer
case (center) differential is locked, half of
the engine’s power is automatically distrib-
uted to the front wheels and half to the rear wheels. When the rear differential is
locked, power going to the rear wheels is
equally distributed, so that both rear
wheels turn at the same speed and torque.
When the front differential is locked, all
four wheels now turn with equal power and
torque. Please be aware that engaging the
differential locks will significantly reduce
the steering ability of the vehicle.
For your safety and the safety of others
and to prevent damage to the vehicle, the
differential locks must not be engaged
when driving on paved roads. It is impor-
tant to understand that during
on-road/paved driving, differentials are
absolutely necessary for providing the es-
sential control and steering ability of the
vehicle. The differential locks, therefore,
must not be engaged when driving on
paved roads and should only be used to
the extent necessary to negotiate off-road
conditions which cannot be handled by the
systems (automatic 4-ETS, the ESP, manu-
al switch position “LOW” of transfer case)
this vehicle comes equipped with.

150 Controls in detailDifferential locksSwitching differential locks on and off
The switch is located in the center console.
1Transfer case (center) differential lock
2Rear axle differential lock
3Front differential lock
4Engagement indicator lamps (yellow)
5Function indicator lamps (red)Switching differential locks on
Transfer case differential lock

Press switch1.
The yellow engagement indicator
lamp4 for the transfer case differen-
tial lock comes on.
The ESP warning lampv comes on.
When the differential lock engagement
operation has been completed, the red
function indicator lamp5 comes on.The message
ABS NOT AVAILABLE –
DIFFERENTIAL LOCKED
appears in the
multifunction display.
The ESP warning lampv and the
ABS- warning lamp in the instru-
ment cluster come on.
Once the transfer case differential lock
is switched on, you can now, if needed,


switch on rear axle differential
lock2
or


switch on rear axle differential lock
and front differential lock2
and3.
iThe differential locks can only be
switched on in the sequence 1,
2,3.
!To avoid damage to the transfer case
and differential locks:

Engage differential locks only at low
speed (walking speed, not more
than 5 mph).


Do not engage differential locks if
the driving wheels are spinning due
to lack of traction.


Do not engage on paved roads.

151 Controls in detail
Differential locks
Rear axle differential lock
Press switch2.
The yellow engagement indicator
lamp4 comes on first, followed by the
red function indicator lamp5.
The rear axle differential lock is
switched on.
Front differential lock

Press switch 3.
The yellow engagement indicator
lamp4 comes on first, followed by the
red function indicator lamp5.
The front differential lock is switched
on. Switching differential locks off
There are two different methods to disen-
gage differential locks:


You can switch the differential locks off
in reverse order (3, 2,1).


To switch off all differential locks at the
same time:
Press switch1.
The yellow engagement indicator
lamps4 go out first. The red func-
tion indicator lamps5 go out
when the switching process has
been carried out in the differential.To activate the ESP, BAS and ABS systems,
drive again for three seconds using a con-
stant driving style.
All messages in the multifunction display
disappear. The ESP warning lampv
and the ABS- warning lamp in the in-
strument cluster go out.
iIf the function lamps do not go out
when the differential locks are disen-
gaged, bring vehicle to a stop and then
continue driving. Changing the vehicle
load can help to disengage locks. Warning!
G
Always remember to disengage the differen-
tial locks when returning to drive on paved
roads, see “A few words about differentials
and differential locks” (
page 149).

169 Controls in detail
Driving systems
Driving systems
The driving systems of your vehicle are de-
scribed on the following pages:

Cruise control, with which the vehicle
can maintain a preset speed.


Rear Parking Assist*, with which you
can assist your parking maneuvers.
The BAS, ABS, ESP, 4-ETS and EBB driving
systems are described in the “Safety and
Security” section (
page 74).
Cruise control
Cruise control automatically maintains the
speed you set for your vehicle.
Use of cruise control is recommended for
driving at a constant speed for extended
periods of time. You can set or resume
cruise control at any speed over 20 mph
(30 km/h).
The cruise control function is operated by
means of the cruise control lever.
The cruise control lever is the uppermost
lever found on the left-hand side of the
steering column (
page 23).
iThe cruise control should not be acti-
vated during-off road driving.
Warning!
G
Cruise control is a convenience system de-
signed to assist the driver during vehicle op-
eration. The driver is and must always
remain responsible for the vehicle speed
and for safe brake operation.
Only use cruise control if the road, traffic
and weather conditions make it advisable to
travel at a steady speed.

The use of cruise control can be danger-
ous on winding roads or in heavy traffic
because conditions do not allow safe
driving at a steady speed.


The use of cruise control can be danger-
ous on slippery roads. Rapid changes in
tire traction can result in wheel spin and
loss of control.


Deactivate cruise control when driving
in fog.
The “Resume” function should only be oper-
ated if the driver is fully aware of the previ-
ously set speed and wishes to resume this
particular preset speed.

212 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 gear selector lever to positionN. Try
to keep the vehicle under control by cor-
rective steering action.Road salts and chemicals can adversely af-
fect braking efficiency. Increased pedal
force may become necessary to produce
the normal brake effect.
Depressing the brake pedal periodically
when traveling at length on salt-strewn
roads can bring road-salt-impaired braking
efficiency back to normal.
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.
For more information, see “Winter driving”
(
page 240).
iFor information on driving with snow
chains, see “Snow chains”
(page 241).
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 75).
Warning!
G
Make sure not to endanger any other road
users when carrying out these braking ma-
neuvers.
Warning!
G
If the vehicle becomes stuck in snow, make
sure snow is kept clear of the exhaust pipe
and from around the vehicle with the engine
running. Otherwise, deadly carbon monox-
ide (CO) gases may enter vehicle interior re-
sulting 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.

214 OperationDriving instructions
Read 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 74)


ESP (
page 78)


4-ETS (
page 77)


Differential lock (
page 148)


Transfer case (
page 145)
Off-road driving rules

Engage the transfer case in position
LOW before driving under off-road con-
ditions (
page 145).

If necessary activate differential locks
(page 150).
The ABS, BAS and ESP are switched off
automatically when the differential
locks are activated.

Fasten items being carried as securely
as possible (
page 180).
Warning!
G
Drive slowly in unknown terrain. This will
make it easier to recognize unexpected ob-
stacles and avoid damage to the vehicle.
To help avoid the vehicle rolling over, never
turn it around on steep inclines. If the vehi-
cle cannot complete the attempted climb,
back it down in reverse gear.
Do not drive along the side of a slope (dan-
ger of vehicle rollover). If in doing so the ve-
hicle begins to show a tendency to roll,
immediately steer into a line of gravity
(straight up or downhill).
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.