2008 MERCEDES-BENZ GL450 trailer

Contents
Power tilt/sliding sunroof* ................ 251
Opening and closing ..................... 251
Synchronizing ............................... 253
Driving systems ................................. 255
Cruise control............................... 255
Distronic* (Canada only) .............. 260
Distance warning function*
(Canada only) ............................... 272
Downhill Speed Regulation
(DSR) ............................................ 273
Off-road driving program
(Vehicles without
enhanced off-road package*) ....... 277
Air suspension program ............... 278
Adaptive Damping System
(ADS)* .......................................... 278
Vehicle level control ..................... 279
Parktronic system* ...................... 288
Rear view camera* ....................... 293Loading .............................................. 295
Carriers* ...................................... 295
Loading instructions..................... 301
Cargo tie-down rings .................... 302
Hooks........................................... 304
Expanding cargo compartment .... 304
Cargo compartment cover blind... 310
Cargo net* ................................... 312
Useful features .................................. 315
Storage compartments ................ 315
Parcel nets ................................... 319
Cup holders.................................. 320
Ashtrays ....................................... 321
Cigarette lighter ........................... 323
Power outlets ............................... 324
Floormats ..................................... 325
Seat cover under third-row seats . 326
Heated steering wheel* ............... 327
Telephone* .................................. 328
Tele Aid ........................................ 331
Garage door opener ..................... 338
Compass ...................................... 344
Infrared reflecting windshield* ..... 344
Operation......................................... 345
The first 1000 miles (1500 km) ......... 346
Driving instructions ........................... 347
Drive sensibly – save fuel............. 347
Drinking and driving ..................... 347
Pedals .......................................... 347
Power assistance ......................... 348
Brakes.......................................... 348
Driving off .................................... 350
Parking......................................... 350
Tires ............................................. 351
Hydroplaning................................ 352
Tire traction ................................. 352
Tire speed rating .......................... 353
Winter driving instructions ........... 353
Standing water............................. 355
Off-road driving ............................ 355
Trailer towing ............................... 364
Passenger compartment .............. 370
Driving abroad ............................. 370
Control and operation of radio
transmitters ................................. 370
Catalytic converter
(gasoline engine).......................... 371
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106 Safety and Security
Driving safety systems
Switching on the ESP®
Press ESP® switch1.
The ESP
® warning lampv in the
instrument cluster goes out.
You are now again in normal driving
mode.For more information, see “Practical hints”
(
page 435).
Off-road – ESP
®
With the off-road driving program switched
on (
page 277), or with the transmission
in LOW RANGE* mode (
page 201), the
ESP® designed for off-road use is automat-
ically activated. At speeds below 27 mph
(45 km/h), the ESP
® assists in over-/un-
dersteering, thus improving vehicle trac-
tion.
ESP
® Trailer Stabilization
If the trailer you are towing should begin to
sway, the rig can only be stabilized by
immediately applying the brakes hard.
Steering during this maneuver will not help
to stabilize the rig.
ESP
® will assist you in such situations.
ESP® recognizes when the trailer starts
swaying and will apply the brakes to re-
duce the vehicle speed to a non-critical
speed that allows the vehicle-trailer combi-
nation to stabilize.The ESP
® Trailer Stabilization is functional
at vehicle speeds above approximately
40 mph (65 km/h) when the ESP
® is
switched on.
Warning!G
When the ESP® warning lampv is
illuminated continuously, the ESP® is
switched off or is not operational due to a
malfunction.
Adapt your speed and driving to the prevail-
ing road conditions and to the non-operating
status of the ESP
®.
!Avoid spinning of a drive wheel for an ex-
tended period of time with the ESP® switched
off. This may cause serious damage to the
drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
WarningG
The system will not be able to assist when
the trailer jackknifes

on wet or icy roads

on roads with slippery surface

in sand or gravel
Trailers with a high center of gravity may tip
over before the system recognizes swaying
of the trailer.
iIf the ESP® has switched off due to a mal-
function, ESP® cannot stabilize the rig.
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197 Controls in detail
Automatic transmission
On uphill grades with a gradient angle of
more than 5°, the hill start assist system
maintains the pressure in the brake sys-
tem for approximately 1 second after you
have released the brake pedal. Therefore,
you can start off smoothly without the
vehicle moving immediately after releasing
the brake pedal.
The hill start assist system is inactive

when starting off on a level road or
downhill grades

with the transmission in neutral
positionN

with the parking brake set

if the ESP® has switched off due to a
malfunctionTowing a trailer
If you tow a trailer, note the following
points:

Manually shift to a lower gear range
(
page 197) if the transmission hunts
between gears on inclines.
A lower gear range and reduction of
speed reduces the chance to overload
or overheat the engine.
For more information on trailer towing, see
the “Operation” section (
page 364).
Gear ranges
With the automatic transmission 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 left gearshift button on the steering
wheel gearshift control, and reverse the
gear range limit by pressing the right gear-
shift button on the steering wheel gearshift
control (
page 198).The selected gear range appears in the
multifunction display.
1Current gear range
Effect
ïThe transmission shifts through
sixth gear only.
îThe transmission shifts through
fifth gear only.
éThe transmission shifts through
fourth gear only.
èThe transmission shifts through
third gear only.
With this selection you can use
the braking effect of the engine.
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201 Controls in detail
Transfer case
Transfer case
LOW RANGE mode*
The LOW RANGE mode is available on vehi-
cles with enhanced off-road package*.
In the following situations you should
switch to LOW RANGE mode:

during off-road driving (page 355)

when crossing water (page 360)

when towing up or down on steep
gradients
With the LOW RANGE selected, the
engine’s power delivery and the shifting
behavior of the automatic transmission are
adjusted. Furthermore, the ABS, ESP
® and
4-ETS functions especially adapted to
off-road travel are activated.
For information on driving safety systems
during LOW RANGE mode, see “Driving
safety systems” (
page 101).
For more information on Off-road driving,
see “Off-road driving” (
page 355).Gear Ranges
There are two possible settings.
!Operational or performance test must only
be conducted on a two-axle dynamometer. If
such tests are necessary, contact an authorized
Mercedes-Benz Light Truck Center. You could
otherwise seriously damage the brake system or
the transfer case which is not covered by the
Mercedes-Benz Limited Warranty.
!Because the ESP® operates automatically,
the engine and ignition must be shut off
(SmartKey in starter switch position0 or1 or
KEYLESS-GO* start/stop button in
position0or1) when testing the parking brake
on a brake test dynamometer and such testing
should be no longer than 10 seconds.
Active braking action through the ESP
® may
otherwise seriously damage the brake system
which is not covered by the Mercedes-Benz
Limited Warranty.
iThe vehicle is equipped with permanent
four-wheel drive. Both the front and rear axles
are powered at all times when the vehicle is
being operated.
HIGH
RANGERoad position for all normal
driving situations.
(LOW RANGE mode off)
LOW
RANGEOff-road position for traveling
on rough terrain.
(LOW RANGE mode on)
Also use the off-road position
when driving on-road on steep
gradients, especially when
towing a trailer.
LOW RANGE acts by raising
the engine’s gear ratio. The ve-
hicle travels at roughly third
the speed compared to when
in the HIGH RANGE position,
leading to an increase in the
engine’s drive power.
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281 Controls in detail
Driving systems
Vehicles without enhanced Off-road
Package*
The switch is located on the upper part of
the center console.
1Vehicle level switch
2Indicator lampBasic settings
The following vehicle chassis ride heights
can be selected using the vehicle level
switch in the center console:The following is the approximate change in
ride height for each of the level settings:
LevelDriving situation
RaisedFor off-road driving or driv-
ing in rough terrain. The in-
dicator lamp is on.
HighwayFor driving on paved roads
in fair or better condition.
The indicator lamp is off.
iThe third available level is the high-speed
level that is set automatically.
LevelRide height
Raised+ 3.1 in (80 mm)
Highway+/- 0 in (0 mm)
High-speed- 0.6 in (-15 mm)
iVehicles with ADS*:
Depending on the ADS setting (
page 278), the
vehicle will be lowered to the high-speed level
when traveling at higher speeds. At speeds
below 40 mph (64 km/h) at the latest, it will be
returned to the highway level.
iThe high-speed level is not available if tow-
ing a trailer. For more information on towing a
trailer, see “Trailer towing” (
page 364).
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284 Controls in detail
Driving systems
The following is the approximate change in
ride height for each of the level settings:You can only select the off-road levels be-
low a certain speed. At higher speeds, the
message
Level Selection Not Permitted
appears in the multifunction display.
You can select

Off-road level 1: selectable below
60 mph (96 km/h)

Off-road level 2: selectable below
40 mph (64 km/h)

Off-road level 3: selectable below
20 mph (30 km/h)Off-road levels
LevelRide height
Off-road 3+ 4.3 in (110 mm)
Off-road 2+ 3.1 in (80 mm)
Off-road 1+ 1.2 in (30 mm)
Highway+/- 0 in (0 mm)
High-speed- 0.6 in (-15 mm)
iVehicles with ADS*:
Depending on the ADS setting (
page 278), the
vehicle will be lowered to the high-speed level
when traveling at higher speeds. At speeds be-
low 40 mph (64 km/h) at the latest, it will be re-
turned to the highway level.
iThe high-speed level is not available if tow-
ing a trailer. For more information on towing a
trailer, see “Trailer towing” (
page 364).
Warning!G
Vehicle off-road level 3 is not intended for
use on paved roads. This vehicle level is only
intended for driving on rough terrain under
special requirements.

Only select off-road level 3 if you are
driving on rough terrain under especially
difficult conditions.

Adapt your driving style to the modified
conditions.

Do not exceed a speed of 20 mph
(30 km/h).

Avoid extreme, quick steering move-
ments.

Keep in mind that the vehicle’s driving
characteristics are modified.
You should therefore drive in off-road level 3
with particular caution as it could otherwise
lead to an accident and/or serious injury to
you or others.
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288 Controls in detail
Driving systems
When the highway level is reached, the in-
dicator lamps3 (
page 281) goes out.
The following message appears in the mul-
tifunction display for 5 seconds:
Parktronic system*
The Parktronic system is an electronic
parking aid and designed to assist the
driver during parking maneuvers. It visually
and audibly indicates the relative distance
between the vehicle and an obstacle.
The Parktronic system is automatically
activated when you

switch on the ignition or start the
engine
and

release the parking brake
and

set the automatic transmission to
positionD,R, orN
iThe vehicle is lowered automatically to the
highway level if the vehicle speed is above
60 mph (96 km/h).
Warning!G
Parktronic is a supplemental system. It is
not intended to, nor does it replace, the
need for extreme care. The responsibility
during parking and other critical maneuvers
always remains with the driver.
Special attention must be paid to objects
with smooth surfaces or low silhouettes
(e.g. trailer couplings, painted posts, or road
curbs). Such objects may not be detected by
the system and can damage the vehicle.
The operational function of the Parktronic
system can be affected by dirty sensors,
especially at times of snow and ice. See
“Cleaning the Parktronic system sensors”
(
page 430).
Interference caused by other ultrasonic
signals (e.g. working jackhammers, car
wash, or the air brakes of trucks) can cause
the system to send erratic indications, and
should be taken into consideration.
Warning!G
Make sure no persons or animals are in the
area in which you are maneuvering. You
could otherwise injure them.
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289 Controls in detail
Driving systems
The Parktronic system deactivates at
vehicle speeds exceeding approximately
11 mph (18 km/h). At lower vehicle
speeds the Parktronic system turns on
again.
The Parktronic system also deactivates
when you set the automatic transmission
to positionP or depress the parking brake
pedal.
The Parktronic system monitors the sur-
roundings of your vehicle with six sensors
in the front bumper and four sensors in the
rear bumper.
1Sensors in the front bumperRange of the sensors
To function properly, the sensors must be
free of dirt, ice, snow and slush. Clean the
sensors regularly, being careful not to
scratch or damaging the sensors, see
“Cleaning the Parktronic* system sensors”
(
page 430).
!During parking maneuvers, pay special
attention to objects located above or below the
height of the sensors (e.g. planters or trailer
hitches). The Parktronic system will not detect
such objects at close range and damage to your
vehicle or the object may result.
Ultrasonic signals from outside sources (e.g.
working jackhammers, car wash or the air brakes
of trucks) may impair the operation of the
Parktronic system.
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