2009 MERCEDES-BENZ GL SUV trailer

it is too low for the current operating condi-
tions.
Driving with tyre pressure that is too high or
too low can:
R shorten the service life of the tyres
R increase the likelihood of tyre damage
R have a negative effect on handling charac-
teristics (e.g. by causing aquaplaning)
i The tyre pressure values given for low
loads are minimum values which offer you
good ride comfort characteristics.
However, you can also use the values given
for higher loads. These are permissible and
will not adversely affect the running of the
vehicle.
Also check the tyre pressure of the spare
wheel* or "Minispare" emergency spare
wheel*. H
Environmental note
Check the tyre pressure regularly, at least
every 14 days. Tyre pressure loss warning
While the vehicle is in motion, the tyre pres-
sure loss warning system monitors the set
tyre pressure using the rotational speed of
the wheels. This enables the system to detect
significant pressure loss in a tyre. If the speed
of rotation of a wheel changes as a result of
a loss of pressure, a corresponding warning
message will appear in the multi-function dis-
play. G
Risk of accident
The tyre pressure loss warning system does
not warn you of an incorrectly set tyre pres-
sure. The table on the inside of the fuel filler
flap will help you decide whether the tyre
pressures should be corrected.
The tyre pressure loss warning system does
not replace the need to regularly check your
vehicle's tyre pressures, since an even loss of pressure on several tyres at the same time
cannot be detected by the tyre pressure loss
warning system.
The tyre pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the
tyre is penetrated by a foreign object.
In the event of a sudden loss of pressure, bring
the vehicle to a halt by braking carefully. Do
not make any sudden steering movements
when doing so.
The function of the tyre pressure loss warning
system is limited or delayed if:
R snow chains are fitted to your vehicle's
tyres.
R road conditions are wintry.
R you are driving on sand or gravel.
R you adopt a very sporty driving style (cor-
nering at high speeds or driving with high
rates of acceleration).
R you are towing a very heavy or large trailer.
R you are driving with a heavy load (in the
vehicle or on the roof).
Restarting the tyre pressure loss warn-
ing system Restart the tyre pressure loss warning system
if you have:
R
changed the tyre pressure
R changed the wheels or tyres
R fitted new wheels or tyres
X Before restarting, consult the table of tyre
pressures on the inside of the fuel filler flap
to ensure that the tyre pressure in all four
tyres is set correctly for the respective
operating conditions.
X Observe the notes in the section on tyre
pressures (Y page 180). 182
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You will require considerably more effort to
steer and brake and you could therefore lose
control of the vehicle and cause an accident.
Brakes
G
Risk of accident
Do not change down for additional engine
braking on a slippery road surface. This could
cause the drive wheels to lose their grip and
the vehicle could skid. G
Risk of accident
Make sure that other road users are not
endangered by your braking.
Downhill gradients On long and steep downhill gradients, espe-
cially if the vehicle is laden or towing a trailer,
you must select shift range 1,2or 3in good
time.
i This also applies if you have activated
cruise control, Speedtronic or Distronic*.
This will use the braking effect of the engine,
so less braking will be required to maintain
the speed. This relieves the load on the brake
system and prevents the brakes from over-
heating and wearing too quickly. If you need
additional braking, depress the brake pedal
repeatedly rather than continuously.
Heavy and light loads If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately, but
drive on for a short while. This allows the air-
flow to cool the brakes more quickly. G
Risk of accident
Never depress the brake pedal continuously
while the vehicle is in motion, e.g. never cause
the brakes to rub by applying constant slight
pedal pressure. This causes the brake system
to overheat, increases the braking distance
and can lead to the brakes failing completely. If the brakes have been used only moderately,
you should occasionally test their effective-
ness. To do this, brake more firmly from a
higher speed. This improves the grip of the
brakes.
Wet roads If driving in heavy rain for a prolonged period
of time without braking, there may be a
delayed reaction from the brakes when brak-
ing for the first time. You must brake harder.
You must therefore maintain a greater dis-
tance from the vehicle in front.
After driving on a wet surface, brake firmly
while paying attention to the traffic condi-
tions. This way the brake discs will become
warm, drying more quickly, which will protect
them against corrosion.
Limited braking performance on salted
roads
G
Risk of accident
The layer of salt on the brake discs and the
brake pads/linings may cause a delay in the
braking effect, resulting in a significantly lon-
ger braking distance, which could lead to an
accident.
To avoid this danger, you should:
R occasionally brake carefully, without put-
ting other road users at risk, when you are
driving on salted roads. This helps to
remove any salt that may have started to
build up on the brake discs and the brake
pads/linings.
R maintain a greater distance to the vehicle
ahead and drive with particular care.
R carefully apply the brakes at the end of a
trip and immediately after commencing a
new trip, so that salt residues are removed
from the brake disc. Driving tips
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R
Drive quickly to overcome the rolling resist-
ance. The vehicle could otherwise dig itself
into the sand.
R Drive in the tracks of other vehicles, if pos-
sible. Make sure that the ruts are not too
deep, that the sand is firm enough and that
your vehicle has sufficient ground clear-
ance. Ruts
Observe the following rules when driving
along ruts in off-road terrain or on roads with
loose gravel:
! Check that the ruts are not too deep and
that your vehicle has sufficient clearance.
Otherwise, your vehicle could be damaged
or bottom out and get stuck.
R Select the LOW RANGE off-road gear
(Y page 114).
R Select a higher vehicle level.
R Avoid high engine speeds.
R Select shift range 1.
R Drive slowly.
R Where ruts are too deep, drive with the
wheels on one side on the middle section
of turf if possible. Driving abroad
Points to remember
An extensive Mercedes-Benz Service network
is also available in other countries. The
Service Hotline's current telephone numbers
for use when you are abroad are to be found
in the "Service24h" chapter of the Service
Booklet.
Only low-octane fuel is available in certain
countries.
You can find further information about fuel
grades on (Y page 172). Symmetrical dipped beam
If your journey takes you to countries where
vehicles are driven on sides of the road oppo-
site to the country in which the vehicle is reg-
istered, your headlamps must be switched to
symmetrical dipped beam. Oncoming traffic
will be dazzled less.
X Have the headlamps switched over at a
qualified specialist workshop, e. g. a
Mercedes-Benz Service Centre. G
Risk of accident
Remember to set the headlamps back to
asymmetrical dipped beam when you return
to driving on the same side of the road as that
of the country in which your vehicle was reg-
istered. You may otherwise dazzle the oncom-
ing traffic and could cause an accident. Trailer towing*
Folding out the ball coupling
Before you can tow a trailer with your vehicle,
you must fit the ball coupling.
The telescopic lever is under the boot/lug-
gage compartment mat on the left-hand side. G
Risk of accident
Make sure that the ball coupling is fully
engaged both when it is folded in and when it
is folded out. The indicator lamp is not lit.
Do not pull the telescopic lever if a trailer is
attached. The trailer could otherwise come
loose. Trailer towing*
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X
Pull telescopic lever :out forwards.
X Pull telescopic lever :upwards.
The ball coupling disengages and folds out
from under the rear bumper.
Indicator lamp ;flashes. The trailer power
socket folds away automatically.
X Guide telescopic lever :back again. X
Press the ball coupling in the direction of
the arrow by hand until it engages in a ver-
tical position.
Indicator lamp ;goes out.
The Trailer tow hitch
Check locking mech. message is shown
in the multi-function display until the ball
coupling is engaged.
X Remove the protective cap from the ball
coupling. Installing the ball coupling (vehicles
with exterior spare wheel*)
Before you can tow a trailer with your vehicle,
you must fit the ball coupling.
There is a key for the ball coupling.
X Make a note of the key number.
You can use this number to obtain a
replacement key from a Mercedes-Benz
Service Centre. G
Risk of injury
If the ball coupling does not engage correctly
when it is mounted, the vehicle/trailer com-
bination is not secured and the trailer could come loose. This could cause an accident. Fit
the ball coupling carefully and make sure that
it engages in position correctly.
The detachable ball coupling is located in the
stowage well under the luggage compartment
floor.
X Take the ball coupling and the key from the
stowage well under the luggage compart-
ment floor (Y page 209). X
Pull protective cap :underneath the
bumper vertically downwards in the direc-
tion of the arrow and out of the ball coupling
recess.
X Place protective cap :in the stowage well
under the luggage compartment floor. X
Pull protective cap ;off the lock in the
handwheel.
X Insert key :into the lock in the hand-
wheel.
X Turn key :anti-clockwise. 194
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i
The key remains inserted when you
remove the ball coupling. X
Pull handwheel ?away from the ball cou-
pling in the direction of the arrow and turn
it clockwise until it engages.
The white dot on the ball coupling is aligned
with the red area on the handwheel.
X Insert the ball coupling vertically up into
ball coupling recess =in the direction of
the arrow until it engages. X
Handwheel ?turns automatically, aligning
green area Aon handwheel ?with white
dot Bon the ball coupling.
X Turn key :to the stop in the direction of
the arrow (lock).
X Remove key :.
X Press protective cap ;onto the lock. G
Risk of accident
The ball coupling is only securely mounted
when the green area on the handwheel is
aligned with the white dot on the ball coupling and the key can be removed. If the ball cou-
pling is not securely mounted, it may come
loose.
The ball coupling must be locked and the key
must be removed when towing a trailer. This
is the only way to guarantee that the ball cou-
pling is secured and cannot come loose while
the vehicle is in motion. If the ball coupling
cannot be locked and the key cannot be
removed, remove the ball coupling and clean
it.
If the ball coupling can still not be fitted
(locked) after it has been cleaned, remove the
ball coupling. The trailer tow hitch must then
not be used to tow a trailer, as safe operation
is not guaranteed.
Have the entire trailer coupling checked at a
qualified specialist workshop. Mercedes-
Benz recommends that you use a Mercedes-
Benz Service Centre for this purpose. In par-
ticular, work relevant to safety or on safety-
related systems must be carried out at a quali-
fied specialist workshop. :
Socket Coupling up and uncoupling a trailer
Coupling up a trailer G
Risk of injury
Never lock, unlock, open or close a vehicle
door or tailgate when coupling up or decou-
pling a trailer. The vehicle level could change
and you could endanger yourself or others. Trailer towing*
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Never press the ADS button* or operate the
level control* while you are coupling up or
decoupling a trailer.
X Make sure the DIRECT SELECT selector
lever is set to P.
X Depress the parking brake.
X Start the engine.
X Set the vehicle to highway level
(Y page 132).
X Set the adaptive damping system (ADS)
setting to AUTOorCOMF (Ypage 129).
X Switch off the engine.
X Close the doors and tailgate.
X Position the trailer level behind the vehicle.
X Couple up the trailer.
X Establish the electrical connection
between the vehicle and the trailer.
i If you have coupled a trailer, the vehicle
will remain at highway level.
The vehicle automatically lowers to high-
way level if you drive faster than 8 km/h
with a trailer. The vehicle is not lowered to
the high-speed level even if you are travel-
ling at higher speeds.
This also applies when using accessories
that are plugged into the socket of the
trailer coupling (e.g. a bicycle rack).
Decoupling a trailer G
Risk of injury
Do not disconnect a trailer with an engaged
overrun brake. Otherwise, your hand could
become trapped between the bumper and
drawbar.
! Do not uncouple a trailer with overrun
brake between the bumper and drawbar,
otherwise your vehicle could be damaged
by the spring action of the overrun brake. X
Make sure the DIRECT SELECT selector
lever is set to P.
X Depress the parking brake.
X Start the engine.
X Close the doors and tailgate.
X Secure the trailer against rolling away. G
Risk of injury
The vehicle is lowered as soon as you discon-
nect the trailer cable. Make sure that nobody
is in the vicinity of the wheel arch or the
underbody. You could otherwise trap yourself
or others.
As soon as you decouple the trailer, the unla-
den vehicle rises slightly. Make sure that you
or others are not injured in the process.
X Remove the trailer cable and decouple the
trailer.
X Switch off the engine. Notes on towing a trailer
G
Risk of accident
When reversing the vehicle towards the
trailer, make sure there is nobody between
the trailer and the vehicle.
Couple and uncouple the trailer carefully. If
you do not couple the trailer to the towing
vehicle correctly, the trailer could become
detached.
Make sure that the following values are not
exceeded:
R the permissible trailer drawbar noseweight
R the permissible trailer load
R the permissible rear axle load of the towing
vehicle
R the maximum permissible gross vehicle
weight of both the towing vehicle and the
trailer
You will find the applicable permissible val-
ues, which must not be exceeded, in the vehi-
cle documents. 196
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You will find the values approved by the man-
ufacturer on the vehicle identification plates
and those for the towing vehicle in the "Tech-
nical data" section.
You will find installation dimensions and loads
in the "Technical data" section
(Y page 297).
The maximum drawbar load of the trailer
drawbar on the ball coupling is 140 kg. How-
ever, the actual noseweight must not exceed
the value given on the trailer coupling or
trailer identification plates. The lowest weight
applies.
! Use a noseweight as close as possible to
the maximum permissible noseweight. Do
not use a noseweight of less than 50 kg,
otherwise the trailer may come loose.
Bear in mind that the payload and the rear
axle load are reduced by the actual nose-
weight.
When towing a trailer, where possible set the
tyre pressures for the permissible gross
weight which you find in the table on the
inside of your vehicle's fuel filler flap (higher
values).
Driving tips i
Observe the notes on ESP ®
trailer stabi-
lisation (Y page 51).
In Germany, the maximum permissible speed
for vehicle/trailer combinations depends on
the type of trailer and is either 80 km/h or
100 km/h. Before beginning the journey,
check the trailer's documents to see what the
maximum permitted speed is. G
Risk of accident
Always observe the maximum speed permit-
ted in Germany for vehicle/trailer combina-
tions, even in countries where higher speeds
are permitted. This lowers the risk of an acci-
dent. When towing a trailer, your vehicle's handling
characteristics will be different in comparison
to when driving without a trailer.
The vehicle/trailer combination:
R is heavier
R is restricted in its acceleration and gradi-
ent-climbing capability
R has an increased braking distance
R is affected more by strong crosswinds
R demands more sensitive steering
R consumes more fuel
On long and steep downhill gradients, you
must select shift range 1,2or 3in good time.
i This also applies if you have activated
cruise control, Distronic* or Speedtronic.
This will use the braking effect of the engine,
so less braking will be required to maintain
the speed. This relieves the load on the brake
system and prevents the brakes from over-
heating and wearing too quickly. If you need
additional braking, depress the brake pedal
repeatedly rather than continuously. G
Risk of accident
Never depress the brake pedal continuously
while the vehicle is in motion, e.g. never cause
the brakes to rub by applying constant slight
pedal pressure. This causes the brake system
to overheat, increases the braking distance
and can lead to the brakes failing completely.
Driving tips
R Maintain a greater distance from the vehi-
cle in front than when driving without a
trailer.
R Avoid braking abruptly. If possible, brake
gently at first to allow the trailer to run on.
Then, increase the braking force rapidly.
R The values given for gradient-climbing
capabilities from a standstill refer to sea
level. When driving in mountainous areas,
note that the power output of the engine,
and consequently the vehicle's gradient- Trailer towing*
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climbing capability, decrease with increas-
ing altitude.
If the trailer swings from side to side:
X Do not accelerate.
X Do not counter-steer.
X Brake if necessary. G
Risk of accident
On no account should you attempt to draw the
vehicle/trailer combination out by increasing
speed. Folding in the ball coupling
i Fold the ball coupling back in if you are
not using the trailer tow hitch. X
Place the protective cap on the ball cou-
pling. G
Risk of injury
Make sure that no persons or animals are in
the pivoting range of the ball coupling. Other-
wise, they could be injured.
X Pull telescopic lever :out forwards.
X Pull telescopic lever :upwards.
The ball coupling disengages and folds out
from under the rear bumper. Indicator
lamp ;flashes.
X Guide telescopic lever :back again. X
Press the ball coupling in the direction of
the arrow until it engages behind the
bumper.
Indicator lamp ;goes out and the mes-
sage in the multi-function display disap-
pears. Removing the ball coupling (vehicles
with exterior spare wheel*)
X Pull the protective cap off the lock in the
handwheel.
X Use the key to unlock the lock in the hand-
wheel.
X Hold the ball coupling. Pull the handwheel
away from the ball coupling and turn it
clockwise until it engages.
The red area on the handwheel is aligned
with the white dot on the ball coupling.
X Pull out the ball coupling downwards.
X Clean the ball coupling if it is dirty.
X Press the protective cap into the ball cou-
pling recess until it engages.
X Make sure that the protective cap is firmly
in place.
Storing the ball coupling X
Place the ball coupling with the key inser-
ted in the ball coupling stowage compart-
ment in the stowage well under the luggage
compartment floor. 198
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