ABS MERCEDES-BENZ G55AMG 2006 W463 User Guide

160 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 157) also en-
hances off-road driving capabilities
(
page 227).
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 161). 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.

161 Controls in detail
Differential locks
Switching 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.
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The 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.


162 Controls in detail
Differential locks
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
lock2 and front differential
lock3.
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 sys-
tems, drive again for three seconds using a
constant 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.
i
If 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 160).


181 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*, which assists
your parking maneuvers.
For information on the BAS, ABS, ESP,
4-ETS, and EBB driving systems, see “Driv-
ing and safety systems” (
page 80).
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).
i
The 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.

225 Operation
Driving instructions
Tire speed rating
Regardless of the tire speed rating, local
speed limits should be obeyed. Use pru-
dent driving speeds appropriate to prevail-
ing conditions.Your vehicle is factory equipped with
“V”-rated tires, which have a speed rating
of 149 mph (240 km/h).
An electronic speed limiter prevents your
vehicle from exceeding a speed of
130 mph (210 km / h).Winter 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.
Warning!G
Even when permitted by law, never operate
a vehicle at speeds greater than the maxi-
mum speed rating of the tires.
Exceeding the maximum speed for which
tires are rated can lead to sudden tire fail-
ure, causing loss of vehicle control and pos-
sibly resulting in an accident and/or serious
injury and possible death, for you and for
others.
i
For information on speed rating for
winter tires, see “Winter driving”
(
page 278).
For additional general information on
tire speed markings on tire sidewall,
see “Tire speed rating” (
page 275).
i
For information on driving with snow
chains, see “Snow chains”
(
page 279).
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.


226 Operation
Driving instructions
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 278).
Standing water
For more information, see “Driving through
water” (
page 231).
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 81).
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-
signed to serve as an ice-warning device and
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.
!
Do not drive through flooded areas or
water of unknown depth. Before driving
through water, determine its depth.
Never accelerate before driving into
water. The bow wave could force water
into the engine and auxiliary equip-
ment, thus damaging them.
If you must drive through standing wa-
ter, drive slowly to prevent water from
entering the passenger compartment
or the engine compartment. Water in
these areas could cause damage to
electrical components or wiring of the
engine or transmission, or could result
in water being ingested by the engine
through the air intake, causing severe
internal engine damage. Any such dam-
age is not covered by the
Mercedes-Benz Limited Warranty.


228 Operation
Driving 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 80)

ESP (page 84)

4-ETS (page 83)

Differential lock (page 159)

Transfer case (page 157)
Off-road driving rules
Engage the transfer case in position
LOW before driving under off-road con-
ditions (
page 157).
If necessary activate differential locks
(
page 161).
The ABS, BAS and ESP are switched off
automatically when the differential
locks are activated.
Fasten items being carried as securely
as possible (
page 192).
Never let the vehicle roll backwards in idle.
You may lose control of the vehicle if you
use only the 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.i
Whenever driving in off-road mode, we
recommend:

Keeping doors, tailgate, windows
and tilt/sliding sunroof 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.


231 Operation
Driving instructions
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:

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 154).

Drive downhill observing the same
rules as driving uphill (
page 230).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).
Make sure you check the water bed.
The ground surface may not be firm
which may result in deeper waters than
expected when driving the vehicle
through it.
!
Only apply the service brake if the vehi-
cle is traveling straight downhill, i.e. in
the line of gravity.
i
The 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.

268 Operation
Tires and wheels
In addition to tire load rating, special load
information may be molded into the tire
sidewall following the letter designating
the tire speed rating6 (
page 266).
No specification given: absence of any text
(like in above example) indicates a
standard load (SL) tire.
XL (Extra Load): designates an extra load
(or reinforced) tire.
Light Load: designates a light load tire.
C, D, E: designates load range associated
with the maximum load a tire can carry at
a specified pressure.
DOT, Tire Identification Number (TIN)
U.S. tire regulations require each new tire
manufacturer or tire retreader to mold a
TIN into or onto a sidewall of each tire
produced.
The TIN is a unique identifier which facili-
tates efforts by tire manufactures to notify
purchasers in recall situations or other
safety matters concerning tires and gives
purchasers the means to easily identify
such tires.
The TIN is comprised of “Manufacturer’s
identification mark”, “Tire size”, “Tire type
code” and “Date of manufacture”.1DOT
2Manufacturer’s identification mark
3Tire size
4Tire type code (at the option of the tire
manufacturer)
5Date of manufacture
i
For illustration purposes only. Actual
data on tires are specific to each vehi-
cle and may vary from data shown in
above illustration.

278 Operation
Winter driving
Before the onset of winter, have your
vehicle winterized at an authorized
Mercedes-Benz Light Truck Center. This
service includes:

Check of anticorrosion and antifreeze
concentration.

Addition of cleaning concentrate to the
water of the windshield and headlamp
cleaning system. Add MB Concentrate
“S” to a premixed windshield washer
solvent/antifreeze which is formulated
for below freezing temperatures
(
page 382).

Battery test. Battery capacity drops
with decreasing ambient temperature.
A well charged battery helps to make
sure that the engine can be started,
even at low ambient temperatures.

Tire change. Mercedes-Benz recom-
mends M+S rated radial-ply tires with a
minimum tread depth of approximately
1/6in (4 mm) on all four wheels for the
winter season.
Winter tires
Always use winter tires at temperatures
below 45°F (7°C) and whenever wintry
road conditions prevail. Not all M+S rated
tires provide special winter performance.
Make sure the tires you use show M+S and
the mountain/snowflake.marking on
the tire sidewall. These tires meet specific
snow traction performance requirements
of the Rubber Manufacturers Association
(RMA) and the Rubber Association of Can-
ada (RAC) and have been designed specif-
ically for use in snow conditions. Using
winter tires is the only way to achieve the
maximum effectiveness of the ABS and
ESP in winter operation.For safe handling, make sure that all
mounted winter tires are of the same make
and have the same tread design.
Always observe the speed rating of the
winter tires installed on your vehicle. If the
maximum speed for which your tires are
rated is below the speed rating of your
vehicle, you must place a notice to this
effect where it will be seen by the driver.
Such notices are available from your tire
dealer or from any authorized
Mercedes-Benz Light Truck Center.
Warning!G
Winter tires with a tread depth under 1/6in
(4 mm) must be replaced. They are no
longer suitable for winter operation.