towing MERCEDES-BENZ GL450 2010 X164 User Guide

Basic settings
The following vehicle chassis ride heights can
be selected using vehicle level control
switch : in the center console:
LevelDriving situationRaised levelFor off-road driving or
driving in rough terrain.
Indicator lamp ; is on.
Highway
level
For driving on paved roads
in fair or better condition.
Indicator lamp ; is off.
iThe third available level is the highspeed
level that is set automatically.
The following is the approximate change in
ride height for each of the level settings:
LevelRide heightRaised level+2.3 in (60 mm)Highway
level13+/-0 in (0 mm)Highspeed
level
-0.6 in (-15 mm)
iVehicles with ADS:
Depending on the ADS setting
(Y page 159), the vehicle will be lowered to
the highspeed 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 highspeed level is not available when
towing a trailer. For more information on
towing a trailer, see “Trailer towing”
(Y page 269).
Raised level
Only select the raised level if appropriate for
the driving situation encountered. Otherwise
the fuel consumption may increase and/or
the handling characteristics of the vehicle
may be unfavorable.
iYou can select the raised level at speeds
up to 40 mph (64 km/h). At higher speeds,
the message Á Level Selection
Not Permitted appears in the
multifunction display.
XStart the engine.
When indicator lamp ; is off:
XPress vehicle level control switch :.
Indicator lamp ; flashes. The vehicle
adjusts to the raised level.
The following message appears in the
multifunction display while the level is
being set:
iThe message can be cleared by pressing
the V, U, & or * button on
the multifunction steering wheel.
When the raised level is reached, indicator
lamp ; comes on continuously and the
following message appears in the
multifunction display for 5 seconds:
Highway level
! Keep in mind that on rough or uneven
roads, adjusting the vehicle to a lower level
may cause the vehicle underbody to come
in contact with the road and result in
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LevelRide heightOff-road
level 3+3.5 in (90 mm)Off-road
level 2+2.3 in (60 mm)Off-road
level 1+1.2 in (30 mm)Highway
level 13+/-0 in (0 mm)Highspeed
level-0.6 in (-15 mm)
i Vehicles with ADS:
Depending on the ADS setting
( Y page 159), the vehicle will be lowered to
the highspeed 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.
i The highspeed level is not available when
towing a trailer. For more information on
towing a trailer, see “Trailer towing”
( Y page 269).
You can only select the off-road levels below
a certain speed. At higher speeds, the
message Level Selection Not
Permitted appears in the multifunction
display.
You can select
R Off-road level 1: selectable below 60 mph
(96 km/h)
R Off-road level 2: selectable below 40 mph
(64 km/h)
R Off-road level 3: selectable below 12 mph
(20 km/h)
Off-road levelsGWarning!
Vehicle off-road level 3 is not intended for use
on paved roads. This vehicle level is intended
for clearing impracticable situations at low
speed exclusively. The vehicle has a very high
center of gravity in off-road level 3. This
increases the overturning hazard.
R Select off-road level 3 exclusively for
clearing impracticable situations at low
speed.
R Adapt your driving style to the modified
conditions.
R Do not exceed a speed of 12 mph
(20 km/h).
R Avoid extreme, quick steering movements.
R Keep in mind 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.
If you are driving too fast while using off-road
level 3, you will see the following message in
the multifunction display:
Reduce speed to under 12 MPH
( 20 km/h )
In addition, an acoustic signal sounds.
i This message cannot be deactivated.
For more information, see “Display
messages” ( Y page 302).
Only use off-road levels when necessary.
Otherwise the fuel consumption may
increase and/or the handling characteristics
of the vehicle may be unfavorable.
XStart the engine.XTurn outer adjustment ring : repeatedly
to position 2 until indicator lamps = of
the desired level flashes.13 Ground clearance: 8.5 in (217 mm)Driving systems163Controls in detailX164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 163Z

iThe message can be cleared by pressing
the V, U, & or * button on
the multifunction steering wheel.
When the highway level is reached, indicator
lamps = go out and the following message
appears in the multifunction display for
5 seconds:
iThe vehicle is lowered to the highway level
automatically if the vehicle speed is above
60 mph (96 km/h).
All-wheel drive (4MATIC)
In vehicles with all-wheel drive (4MATIC),
both axles are powered at all times when the
vehicle is being operated. The 4MATIC
improves traction in conjunction with the
ESP® (Y page 63) and the Electronic Traction
System (4-ETS) (Y page 64).
GWarning!
If a drive wheel is spinning due to insufficient
traction:
RWhile driving off, apply as little throttle as
possible.
RWhile driving, ease up on the accelerator
pedal.
RAdapt your speed and driving style to the
prevailing road conditions.
Failure to observe these guidelines could
cause the vehicle to skid.
The 4MATIC cannot prevent accidents
resulting from excessive speed.
! Do not tow with one axle raised. Doing so
could damage the transfer case, which is
not covered by the Mercedes-Benz Limited
Warranty. All wheels must be on or off the
ground. Observe instructions for towing the
vehicle with all wheels on the ground.
! Only conduct operational or performance
tests on a two-axle dynamometer. If such
tests are necessary, contact an authorized
Mercedes-Benz Center. You could
otherwise seriously damage the brake
system and/or the transfer case which is
not covered by the Mercedes-Benz Limited
Warranty.
iIn winter operation, the maximum
effectiveness of the 4MATIC is only
achieved with winter tires (Y page 257) or
snow chains as required.
Parktronic system
The Parktronic system is an electronic
parking aid with ultrasonic sensors designed
to assist the driver during parking maneuvers.
The Parktronic system indicates the relative
distance between the vehicle and an obstacle
visually and audibly.
The Parktronic system is activated
automatically when
Ryou switch on the ignition
and
Ryou release the parking brake
and
Rthe automatic transmission is in drive
position D, reverse gear R, or neutral
position N
The Parktronic system deactivates at speeds
above approximately 11 mph (18 km/h). At
lower speeds, the Parktronic system
activates again.
The Parktronic system also deactivates when
you shift the automatic transmission into
park position P or engage the parking brake.
The Parktronic system monitors the
surroundings of your vehicle with six sensors
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Vehicle without enhanced off-road package
Vehicle with enhanced off-road package
XSwitching off: Press Parktronic
switch :.
Indicator lamp ; comes on.
XSwitching on: Press Parktronic switch :
again.
Trailer towing
The rear Parktronic sensors will be
deactivated when you have established the
electrical connection between your vehicle
and the trailer you are about to tow.
! The distance between the sensors in the
bumpers and an obstacle is referred to as
the minimum range of the Parktronic. A
trailer hitch will reduce the distance to an
obstacle. Keep this in mind to avoid any
damage.
Parktronic system malfunction
There is a malfunction in the Parktronic
system, if only the red distance segments
illuminate and an acoustic warning sounds.
The Parktronic system will switch off
automatically after 20 seconds and indicator
lamp ; in Parktronic switch : comes on.
XHave the Parktronic system checked at an
authorized Mercedes-Benz Center as soon
as possible.
If only the red distance segments illuminate
and no acoustic warning sounds, the
Parktronic system sensors are dirty (e.g. dirt,
ice, snow and slush). Another cause could be
interference from other radio or ultrasonic
signals (e.g. truck air brakes, car wash, or
jackhammers). The Parktronic system will
switch off automatically after 20 seconds and
indicator lamp ; in Parktronic switch :
comes on.
XSwitch off the ignition.XClean the Parktronic system sensors
(Y page 278).
XSwitch on the ignition.
or
XCheck the Parktronic system operation at
another location to rule out interference
from outside radio or ultrasonic signals.
Rear view camera
The rear view camera is an optical parking aid.
The area behind the vehicle appears in the
COMAND system display as a mirror image,
like in the rear view mirror.
In addition, the rear view camera contains
guidelines to help you with driving in reverse.
GWarning!
Make sure no persons or animals are in or
near the area in which you are parking/
maneuvering. Otherwise, they could be
injured.
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XPress and hold Roadside Assistance
button : for longer than 2 seconds.
A call to a Mercedes-Benz Roadside
Assistance dispatcher will be initiated. The
indicator lamp in Roadside Assistance
button : will flash while the call is in
progress. The message Connecting
Call will appear in the multifunction
display and the COMAND system is muted.
When the connection is established, the
message Call Connected appears in the
multifunction display. The Tele Aid system will
transmit data generating the vehicle
identification number, model, color and
location (subject to availability of cellular and
GPS signals).
i The COMAND system display indicates
that a Tele Aid call is in progress. While the
call is connected you can change to the
navigation menu by pressing the NAVI
button on the COMAND system. Spoken
commands are not available.
A voice connection between the Roadside
Assistance dispatcher and the occupants of
the vehicle will be established.
XDescribe the nature of the need for
assistance.
The Mercedes-Benz Roadside Assistance
dispatcher will either dispatch a qualified
Mercedes-Benz technician or arrange to tow
your vehicle to the nearest authorized
Mercedes-Benz Center. For services such as
labor and/or towing, charges may apply.
Refer to the Roadside Assistance manual for
more information.
Sign and Drive services (USA only):
Services such as a jump start, a few gallons
of fuel or the replacement of a flat tire with
the vehicle spare wheel are obtainable at no
charge.
iIf the indicator lamp in Roadside
Assistance button : is flashing
continuously and there was no voice
connection to the Customer Assistance
Center established, then the Tele Aid
system could not initiate a Roadside
Assistance call (e.g. the relevant cellular
phone network is not available). The
message Call Failed appears in the
multifunction display.
XTerminating calls: Press button ~ on
the multifunction steering wheel.
or
XPress the respective button for ending a
telephone call on the COMAND system.
Information button
XOpen the front armrest storage
compartment (Y page 208).
XPress and hold Information button : for
longer than 2 seconds.
A call to the Customer Assistance Center
will be initiated. The indicator lamp in
Information button : will flash while the
call is in progress. The message
Connecting Call will appear in the
multifunction display and the COMAND
system is muted.
When the connection is established, the
message Call Connected appears in the
multifunction display. The Tele Aid system will
transmit data generating the vehicle
identification number, model, color and
location (subject to availability of cellular and
GPS signals).
i The COMAND system display indicates
that a Tele Aid call is in progress. While the
call is connected you can change to the
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Example illustration: Tire inflation pressures for allapproved, factory equipped tires
When a tire size is specified, the tire inflation
pressure that follows applies to that
particular tire size only.
Example illustration: Tire inflation pressures forparticular tire sizes
Some tire inflation pressure labels may only
show the rim diameter instead of the entire
tire size, e.g. R 18 or 18".
The rim diameter is part of the tire size as
specified on the tire sidewall (Y page 251).
Example illustration: Tire inflation pressuresspecific to rim diameter
iWhen towing a trailer, inflate the tires to
the tire inflation pressure as specified for a
fully loaded vehicle.
Potential problems associated with
underinflated and overinflated tires
Underinflated tires
GWarning!
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated.
Underinflated tires can
Rcause excessive and uneven tire wear
Radversely affect fuel economy
Rlead to tire failure from being overheated
Radversely affect handling characteristics
Overinflated tires
GWarning!
Follow recommended tire inflation pressures.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
Overinflated tires can
Radversely affect handling characteristics
Rcause uneven tire wear
Rbe more prone to damage from road
hazards
Radversely affect ride comfort
Rincrease stopping distance
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XStep 3: Subtract the combined weight of
the driver and passengers from
XXX kilograms or XXX lbs.XStep 4: The resulting figure equals the
available amount of cargo and luggage load
capacity. For example, if the “XXX” amount
equals 1 400 lbs and there will be five
150 lbs passengers in your vehicle, the
amount of available cargo and luggage load
capacity is 650 lbs
(1 400 - 750 (5 x 150) = 650 lbs).XStep 5: Determine the combined weight of
luggage and cargo being loaded on the
vehicle. That weight may not safely exceed
the available cargo and luggage load
capacity calculated in step 4.XStep 6 (if applicable): If your vehicle will
be towing a trailer, load from your trailer
will be transferred to your vehicle. Consult
this manual to determine how this reduces
the available cargo and luggage load
capacity of your vehicle ( Y page 246).
The following table shows examples on how
to calculate total and cargo load capacities
with varying seating configurations and
number and size of occupants. The following
examples use a load limit of 1 500 lbs. This
is for illustration purposes only. Make sure
you are using the actual load limit for your
vehicle stated on the vehicle’s Tire and
Loading Information placard ( Y page 243).
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Trailer towingGWarning!
Failure to use proper equipment and driving
technique can result in a loss of vehicle
control when towing a trailer.
Improper towing or failure to follow the
instructions in this manual can result in
vehicle damage and/or serious personal
injury. Follow the guidelines below carefully
to assure safe trailer operation.
Contact an authorized Mercedes-Benz Center
should you require an explanation of
information contained in this manual.
Trailer hitch
R Only install a trailer hitch receiver approved
for your vehicle.
For information on availability and
installation, contact an authorized
Mercedes-Benz Center.
R The bumpers on your vehicle are not
designed for use with clamp-type hitches.
Do not attach rental hitches or other
bumper-type hitches to them.
R To reduce the possibility of damage,
remove the hitch ball adapter from the
receiver when not in use.
Electrical connections
The vehicle is prewired to accept the seven-
wire harness included in the Mercedes-Benz
approved trailer hitch receiver kit.
i A four-pole conversion plug is available
from your authorized Mercedes-Benz
Center as a spare part.
For further information, contact an
authorized Mercedes-Benz Center.
Vehicle and trailer weights and ratings
The Gross Trailer Weight (GTW) is the weight
of the trailer plus the weight of all cargo,
equipment, luggage, etc. loaded on the
trailer. The maximum permissible GTW to be
towed: 7 500 lb (3 402 kg).
Trailer Tongue Weight Rating (TWR) is the
maximum permissible weight on the trailer
tongue: 600 lb (272 kg) limit for Mercedes-
Benz approved hitch receiver.
Loading a trailer
R When loading a trailer, you should observe
that neither the permissible GTW, nor the
Gross Vehicle Weight Rating (GVWR) are
exceeded. The GVWR is indicated on the
certification label located on the driver’s
door B-pillar ( Y page 242).
Maximum permissible values are listed on
the safety compliance certification labels
for the vehicle and for the trailer to be
towed.
The lowest value listed must be selected
when determining how the vehicle and
trailer are loaded.
R The tongue weight at the hitch ball must be
added to the rear axle weight to prevent
exceeding the rear Gross Axle Weight
Rating (GAWR). The GAWR is indicated on
the certification label located on the
driver’s door B-pillar ( Y page 242).
i Mercedes-Benz recommends loading the
trailer in such a manner that it has a tongue
weight between 8 % and 15 % of the GTW.
i The weight of other accessories,
passengers and cargo will reduce the
maximum trailer weight and tongue weight
your vehicle can tow.
Checking weights of vehicle and trailer
R To assure that the towing vehicle and trailer
are in compliance with the maximum
permissible weight limits, have the loaded
rig (towing vehicle including driver,
passengers and cargo, trailer fully loaded)
weighed on a commercial scale.
R Check the vehicle’s front and rear gross
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The values as measured must not exceed
the weight limits listed under “Vehicle and
trailer weights and ratings” ( Y page 269).
Coupling a trailer GWarning!
While you are coupling or decoupling a trailer,
make sure nobody locks or unlocks the
vehicle and/or opens or closes doors or the
tailgate.
The vehicle’s level could change and you
could endanger yourself and/or others as a
result.
Make sure that you do not operate the ADS
button or the vehicle level control system
when coupling/decoupling the trailer.
Observe maximum permitted trailer
dimensions (width and length).
Most states and all Canadian provinces
require
R safety chains between the towing vehicle
and the trailer
The chains should be criss-crossed under
the trailer tongue. They must be attached
to the hitch receiver, and not to the
vehicle’s bumper or axle.
Make sure to leave enough slack in the
chains to permit turning corners.
R a separate brake system at various trailer
weights
R a break-away switch on trailers with a
separate brake system.
Check with your local state laws for specific
requirements.
The switch activates the trailer brakes in
the possible event that the trailer might
separate from the tow vehicle.
! Do not connect a trailer brake system (if
trailer is so equipped) directly to the
vehicle’s hydraulic brake system, as your
vehicle is equipped with antilock brakes. If
you do, neither the vehicle’s brakes nor the
trailer’s brakes will function properly.
i The provided vehicle electrical wiring
harness for trailer towing has a brake signal
wire for hook-up to a brake controller.XMake sure the automatic transmission is in
park position P (Y page 115).XEngage the parking brake for the vehicle
( Y page 112).XStart the engine ( Y page 108).XSelect the highway level ( Y page 159).XVehicles with Adaptive Damping System
(ADS):
Set the ADS to AUTO or COMF
( Y page 159).XTurn off the engine ( Y page 113).XClose all doors and the tailgate.XAttach the trailer.XPlug in all electrical connectors.
i
When you are towing a trailer, the vehicle
level always remains in the highway setting.
The following applies additionally when
towing a trailer:
R The vehicle is lowered to the highway
level when it reaches a speed of 5 mph
(8 km/h) if not set to highway level.
R The highspeed level is not available.
The restrictions that apply to towing also
apply when using accessories that are
connected to the trailer power socket, such
as a bicycle rack.
Towing a trailer
There are many different laws, including
speed limit restrictions, having to do with
trailer towing. Make sure your rig will be legal,
not only for where you reside, but also for
where you will be driving. A good source for
this information can be the police or local
authorities.
Note the following, when driving with a trailer:
R In order to gain skill and an understanding
of the vehicle’s behavior, you should
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practice turning, stopping and backing up
in an area which is free of traffic.
R Before you start driving check the
- trailer hitch
- break-away switch
- safety chains
- electrical connections
- lighting
- tires
R Adjust the mirrors ( Y page 94) to permit
unobstructed view beyond rear of trailer.
R If the trailer has electric brakes, start your
vehicle and trailer moving slowly, and then
apply only the trailer brake controller by
hand to make sure the brakes are working
properly.
R Always secure items in the trailer to
prevent load shifts while driving.
R When towing a trailer, check occasionally
to make sure the load is secure, and that
trailer lighting and brakes (if so equipped)
are functioning properly.
R Take into consideration that when towing a
trailer, the handling characteristics are
different and less stable from those when
operating the vehicle without a trailer.
It is important to avoid sudden maneuvers.
R The vehicle and trailer combination is
heavier, and therefore limited in
acceleration and climbing ability, and has a
larger braking distance.
It is more prone to reacting to cross wind
gusts, and requires more sensitive steering
input.
R If possible, do not brake abruptly, but
rather engage the brake slightly at first to
permit the trailer to activate its brake. Then
increase the braking force.
! If the trailer should begin to sway, reduce
the vehicle’s speed immediately.Do not attempt to straighten out the tow
vehicle and trailer by increasing the speed.
R If the transmission shifts between gears on
inclines repeatedly, shift to a lower gear
range manually ( Y page 118). Select 4, 3 ,
2 or 1.
A lower gear and reduction of speed
reduces the chance of engine overloading
and/or overheating.
R On very steep inclines, not manageable
with automatic transmission in gear range
1 , switch on off-road driving program
( Y page 158) or LOW RANGE mode
( Y page 120).
R When going down an incline, shift into a
lower gear and use the engine’s braking
effect.
Avoid riding the brakes, thus overheating
the vehicle and trailer brakes (if so
equipped).
R If the engine coolant rises to an extremely
high temperature when the air conditioning
is on, turn off the air conditioning system.
Engine coolant heat can be additionally
vented by opening the windows, switching
the climate control fan speed to high and
setting the temperature control to the
maximum.
R During a passing maneuver extreme care
must be exercised since your vehicle with
a trailer will require additional passing
distance ahead than when driving without
a trailer.
Because your vehicle and trailer is longer
than your vehicle alone, you will also need
to go much farther ahead of the passed
vehicle before you can return to your lane.
Decoupling a trailer GWarning!
While you are coupling or decoupling a trailer,
make sure nobody locks or unlocks the
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