2007 MERCEDES-BENZ G55AMG engine

165 Controls in detail
Automatic transmission
Effect
ëNeutral
No power is transmitted from the
engine to the drive axle. When
the brakes are released, the
vehicle can be moved freely
(pushed or towed).
To avoid damage to the trans-
mission, never engage neutral
positionN while driving except:

to coast when vehicle is in
danger of skidding (e.g. on
icy roads) when the ESP
® is
deactivated or malfunction-
ing

when you have to shift the
transfer case
êDrive
The transmission shifts
automatically. All forward gears
are available.
!Coasting the vehicle, or driving for any other
reason with gear selector lever in neutral
positionN can result in transmission damage
that is not covered by the Mercedes-Benz
Limited Warranty.
Warning!G
Getting out of your vehicle with the gear
selector lever not fully engaged in park
positionP is dangerous. Also, park
positionP alone is not intended to or capa-
ble of preventing your vehicle from moving,
possibly hitting people or objects.
Always set the parking brake in addition to
shifting to park positionP (
page 62).
When parked on an incline, turn the front
wheels towards the road curb.
Do not park this vehicle in areas where com-
bustible 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.
Warning!G
When leaving the vehicle, always remove the
SmartKey from the starter switch, take it
with you, and lock the vehicle. Do not leave
children unattended in the vehicle, or with
access to an unlocked vehicle. Children
could move the gear selector lever from
park positionP, which could result in an
accident and/or serious personal injury.

166 Controls in detail
Automatic transmission
Driving tips
Accelerator position
Your driving style influences the
transmission’s shifting behavior:
Less throttle Earlier upshifting
More throttle Later upshifting
Kickdown
Use kickdown when you want maximum
acceleration.
Press the accelerator past the point of
resistance.
Depending on the engine speed the
transmission shifts into a lower gear.
Ease on the accelerator when you have
reached the desired speed.
The transmission shifts up again.Stopping
When you stop briefly, e.g. at traffic lights:
Leave the transmission in gear.
Hold the vehicle with the brake.
When you stop for a longer period of time
with the engine idling and/or on a hill:
Set the parking brake.
Move the gear selector lever to park
positionP.Maneuvering
When you maneuver in tight areas,
e.g. when pulling into a parking space:
Control the vehicle speed by gradually
releasing the brakes.
Accelerate gently.
Never abruptly step on the accelerator.
Working on the vehicle
Warning!G
When working on the vehicle, set the
parking brake and move gear selector lever
to park positionP. Otherwise the vehicle
could roll away.

167 Controls in detail
Automatic transmission
Gear ranges
With the gear selector lever in drive
positionD, you can select a gear range for
the automatic transmission to operate
within.
You can limit the gear range by pressing
the gear selector lever to the left (D-), and
reverse the gear range limit by pressing
the gear selector lever to the right (D+)
(
page 168).
The current gear range appears in the
multifunction display.
1Current gear range
!If the transfer case is in off-road driving
position LOW, the automatic transmission will
not shift up automatically, even when the engine
has reached the speed limit for that gear. There
is a risk of damaging the engine.
It is very important to make sure the permissible
engine speed is not exceeded.
Effect
ïThe transmission shifts through
sixth gear only (applies to
vehicles with 7-speed automatic
transmission only).
îThe transmission shifts through
fifth gear only (applies to
vehicles with 7-speed automatic
transmission only).
éThe transmission shifts through
fourth gear only.
Effect
èThe transmission shifts through
third gear only.
With this selection you can use
the braking effect of the engine.
çThe transmission shifts through
second gear only.
Allows the use of engine’s brak-
ing power when driving

on steep downgrades

in mountainous regions

under extreme operating
conditions
æThe transmission operates in
first gear only.
For maximum use of engine’s
braking effect on very steep or
lengthy downgrades.

168 Controls in detail
Automatic transmission
One-touch gearshifting
With the gear selector lever in drive
positionD, you can limit or extend the gear
range.Limiting gear range
Briefly press the gear selector lever to
the left in the D–direction.
The transmission will shift to the next
lower gear as permitted by the shift
program. This action simultaneously
limits the gear range of the transmis-
sion (
page 167).Extending gear range
Briefly press the gear selector lever to
the right in the D+direction.
The transmission will shift to the next
higher gear as permitted by the shift
program. This action simultaneously
extends the gear range of the transmis-
sion.
!Allow engine to warm up under low load use.
Do not place full load on the engine until the
operating temperature has been reached.
Shift into reverse gearR or park positionP only
when the vehicle is stopped.
Warning!G
On slippery road surfaces, never downshift
in order to obtain braking action. This could
result in drive wheel slip and reduced
vehicle control. Your vehicle’s ABS will not
prevent this type of loss of control.
iTo avoid overrevving the engine when down-
shifting, the transmission will not shift to a lower
gear if the engine’s max. speed would be
exceeded.
iIf you press on the accelerator when the en-
gine has reached its rpm limit, the transmission
will upshift beyond any gear range limit selected.

169 Controls in detail
Automatic transmission
Canceling gear range limit
Press and hold the gear selector lever
in the D+direction until
Dreappears in
the multifunction display (
page 164).
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
acceleration and deceleration. This will
involve shifting down one or more
gears.Emergency operation
(Limp-Home Mode)
If vehicle acceleration becomes less
responsive or sluggish or the transmission
no longer shifts, the transmission is most
likely operating in limp-home (emergency
operation) mode. In this mode only second
gear and reverse gear can be selected.
Stop the vehicle in a safe location.
Move the gear selector lever to park
positionP.
Turn off the engine.
Wait at least 10 seconds before
restarting.
Restart the engine.
Move the gear selector lever to
positionD (for second gear) or
positionR.
Have the transmission checked at an
authorized Mercedes-Benz Light Truck
Center as soon as possible.

170 Controls in detail
Transfer case
For more information on off-road driving,
see “Off-road driving” (
page 253).
Transfer case position
Switching transfer case
The transfer case switch is located on the
lower part of the center console.
Transfer case switch
The current gear position of the transfer
case appears in the multifunction display.
1Transfer case indicator
HHIGH
Road position
LLOW
Off-road position
This position is intended for driv-
ing off-road and step gradients.
The transmission will not upshift
automatically to the next higher
gear range when driving at the
rpm limit.
The transfer case supports the
engine’s driving force
(approximately
1/2 speed).
Output is therefore increased.
NNeutral
No power is transmitted from the
engine to the drive axle.

171 Controls in detail
Transfer case
Switching from HIGH to LOW
Press upper half (“LOW”) of the
transfer case switch.
Once the shift is complete, gear
position
L appears in the transfer case
indicator1 (
page 170).
Move the gear selector lever to drive
positionD.Switching from LOW to HIGH
Press lower half (“HIGH”) of the
transfer case switch.
Once the shift is complete, gear
position
H appears in the transfer case
indicator1 (
page 170).
Move the gear selector lever to drive
positionD.
Warning!G
Always wait until the procedure of shifting
from HIGH to LOW – and from LOW to HIGH
– has been entirely completed. During this
procedure do not:

switch off the engine

shift the automatic transmission into
another gear
If you do not wait until the shifting proce-
dure has been entirely completed then it
might not be correctly performed. The
transfer case might be in neutral, thus inter-
rupting the transfer of power between the
engine and the drive axle.
The vehicle is then freely movable, even if a
gear has been selected, and could uninten-
tionally be set into motion – particularly on
up – or downhill grades. This could lead to
an accident and cause injury to yourself and
others.
Please observe related messages appearing
in the multifunction display (
page 172).
!The shift procedure can only be performed
when:

the engine is running

the gear selector lever for the automatic
transmission is in neutral positionN

the vehicle is not at standstill

the vehicle speed does not exceed 25 mph
(40 km/h)
iIf the shift procedure does not take place
press upper half (“LOW”) of the transfer case
switch once more.
!The shift procedure can only be performed
when:

the engine is running

the gear selector lever for the automatic
transmission is in neutral positionN

the vehicle is not at standstill

the vehicle speed does not exceed 40 mph
(70 km/h)
iIf the shift procedure does not take place
press lower half (“HIGH”) of the transfer case
switch once more.

174 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
farther 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
possible.
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
engine’s power will go to that wheel
because the power will take the path of
least resistance. Meanwhile, the opposite
wheel, sitting 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 (4-ETS)
addresses 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 4-ETS in this vehicle
feature such intelligent limited-slip
differential technology, ideally suited for
on-road and light off-road driving. Transfer
case position LOW (
page 170) also
enhances off-road driving capabilities
(
page 253).
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
switches in sequential order (center, rear,
front) (
page 175). When the transfer
case (center) differential is locked, half of
the engine’s power is automatically
distributed 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
important to understand that during
on-road/paved driving, differentials are
absolutely necessary for providing the
essential 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®,
manual switch position “LOW” of transfer
case) this vehicle comes equipped with.