2003 MERCEDES-BENZ G55AMG Owner's Manual

137 Controls in detail
Automatic transmission
Canceling gear range limit
Press and hold the selector lever in the
D+direction until D reappears in the
tachometer display field.
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.
Gear ranges
With the selector lever in positionD, you
can limit the transmission’s gear range by
pressing the lever to the left (D-), and re-
verse the gear range limit by pressing the
lever to the right (D+).
The selected gear range will appear in the
tachometer display field. If you press on
the accelerator when the engine has
reached its rpm limit, the transmission will
upshift beyond any gear range limit
selected.
!If the transfer case is in off-road driving
position LOW, the automatic transmis-
sion 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 that
the permissible engine speed is not ex-
ceeded.
Gear
range
Effect
é
The transmission shifts
through fourth gear only.
è
The transmission shifts
through third gear only.
With this selection you can
use the braking effect of the
engine.

138 Controls in detailAutomatic transmission
Gear selector lever position
Gear
range
Effect
ç
The transmission shifts
through second gear only.
Allows the use of engine’s
braking power when driving

on steep downgrades


in mountainous regions


under extreme operating
conditions
æ
The transmission operates
only in first gear
For maximum use of engine’s
braking effect on very steep
or lengthy downgrades.
Effect
P
Park position
Selector position when the vehicle is
parked. Only place selector lever in
positionP when vehicle is stopped.
The park position is not intended to
serve as a brake when the vehicle is
parked. Rather, the driver should al-
ways set the parking brake in addi-
tion to placing the selector lever in
positionP to secure the vehicle.
The key can only be removed from
the starter switch with the selector
lever in positionP. With the key re-
moved, the selector lever is locked in
positionP.
R
Reverse gear
Place selector lever in positionR only
when vehicle is stopped.
Effect
N
Neutral
No power is transmitted from the en-
gine to the drive axle. When the
brakes are released, the vehicle can
be moved freely (pushed or towed).
Do not engage N while driving ex-
cept:

to coast when the vehicle is in
danger of skidding (e.g. on icy
roads) when the ESP is deactivat-
ed or malfunctioning


when you have to shift the trans-
fer case
D
Drive
The transmission shifts automatical-
ly. All five forward gears are avail-
able.

139 Controls in detail
Automatic transmission
Accelerator position
Your driving style influences the transmis-
sion’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.
The transmission shifts into a lower
gear.

Ease on the accelerator when you have
reached the desired speed.
The transmission shifts up again.
!Coasting the vehicle, or driving for any
other reason with selector lever inN
can result in transmission damage that
is not covered by the Mercedes-Benz
Limited Warranty.Warning!
G
Getting out of your vehicle with the selector
lever not fully engaged in positionP is dan-
gerous. Also, positionP alone is not intend-
ed to or capable of preventing your vehicle
from moving, possibly hitting people or ob-
jects.
Always set the parking brake in addition to
shifting to positionP (
page 50).
When parked on an incline, turn the front
wheels towards the road curb.
Warning!
G
When leaving the vehicle, always remove the
key from the starter switch, and lock the ve-
hicle. Do not leave children unattended in
the vehicle, or with access to an unlocked
vehicle. Children could move the selector le-
ver from positionP, which could result in an
accident and/or serious personal injury.

140 Controls in detailAutomatic transmissionEmergency operation (Limp Home Mode)
If vehicle acceleration worsens or the
transmission no longer shifts, the trans-
mission is most likely operating in limp
home (emergency operation) mode. In this
mode, only 2nd gear and reverse gear can
be activated.
Stop the vehicle.

Move selector lever toP.

Turn off the engine.

Wait at least ten seconds before re-
starting.

Restart the engine.

Move selector lever to positionD (for
2nd gear) orR.

Have the transmission checked at an
authorized Mercedes-Benz Light Truck
Center as soon as possible.

141 Controls in detail
Transfer case
Transfer case
More information on off-road driving can
be found in the “Operation” section
(page 203).
Gear range
Switching transfer case
The switch is located in the center console.1Transfer case indicator
2Gear range indicator
Transfer case indicator1 in the multifunc-
tion display shows the gear position of the
transfer case.
Switching from HIGH to LOW
H
HIGHRoad position
L
LOWOff-road position
This position is intended for
driving off-road and step gradi-
ents.
The transmission will not up-
shift automatically to the next
higher gear range when driving
at the rpm limit.The transfer case supports the
engine’s driving force (approx.
½ speed). Output is therefore
increased.
N
NeutralNo power is transmitted from
the engine to the drive axle.
!The shift procedure can only be per-
formed when:

The engine is running.


The selector lever for the automatic
transmission is in positionN.


The vehicle speed does not exceed
25 mph (40 km/h).

142 Controls in detailTransfer case
Press upper half1 (“LOW”) of the
transfer case switch.
Once the shift is complete, gear
positionL is displayed in the transfer
case indicator.

Put gear selector in D.
Switching from LOW to HIGH

Press lower half2 (“HIGH”) of the
transfer case switch.
Once the shift is complete, gear
positionH is displayed in the transfer
case indicator.

Put gear selector in D.
Messages in the multifunction display
If a shift was not completed and the multi-
function display shows one of the following
messages:


TC SHIFT CONDITIONS NOT FULFILLEDThe shift does not occur. At least one
shift condition was not met.

Repeat the shift procedure.


TC IN NEUTRAL The shift does not occur. The transfer
case is in neutral. The gear positionN
is displayed in the transfer case
indicator1.

Repeat the shift procedure.


TC SHIFT – CANCELLEDThe shift did not take place.

Repeat the shift procedure.


TRANSFER CASE – VISIT WORKSHOP!There is a malfunction in the system.

Have the vehicle checked at your au-
thorized Mercedes-Benz Light Truck
Center as soon as possible.
More information can be found in the
“Practical hints” section (
page 266).
!The shift procedure can only be per-
formed when:

The engine is running.


The selector lever for the automatic
transmission is in positionN.


The vehicle speed does not exceed
40 mph (70 km/h).
Warning!
G
If TC is in neutral, transmission positionP
will not hold vehicle. The parking brake must
be applied to hold vehicle in place.
iIf the SmartKey is in starter switch
position0 or1, an alarm will sound if
the transfer case is in positionN and
the driver’s door is opened.
Engage transfer case to gear position
HIGH or LOW.

143 Controls in detail
Differential locks
Differential locks
Information on off-road driving is found in
the “Operation” section (
page 203).
Differential locks improve the vehicle’s
tractive power off-road. Switch differential
locks on:


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.

144 Controls in detailDifferential locksA few words about differentials and dif-ferential 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, make this essential function possi-
ble.
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 141) also en-
hances off-road driving capabilities
(
page 203).
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 145). 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 can not be handled by
the systems (automatic 4-ETS, the ESP,
manual switch position “LOW” of transfer
case) this vehicle comes equipped with.