MERCEDES-BENZ GL550 2010 X164 Owner's Manual

maneuvers. Do not use the cruise control
system under such conditions.
When the vehicle is in danger of skidding, shift
the automatic transmission to neutral
position N. Try to keep the vehicle under
control by corrective steering action.
i For information on driving with snow
chains, see “Snow chains” ( Y page 258).
Road salts and chemicals can adversely
affect braking efficiency. Increased pedal
force may become necessary to produce the
normal brake effect.
Depressing the brake pedal periodically when
traveling at length on salt-strewn roads can
bring road-salt-impaired braking efficiency
back to normal.
If the vehicle is parked after being driven on
salt-treated roads, the braking efficiency
should be tested as soon as possible after
driving is resumed.GWarning!
Make sure not to endanger any other road
users when carrying out these braking
maneuvers.
Driving instructions
Drive sensibly – save fuel
To save fuel you should:
R Keep tires at the recommended inflation
pressures.
R Remove unnecessary loads.
R Remove carriers when not in use.
R Remove the crossbars when not in use.
R Allow engine to warm up under low load
use.
R Avoid frequent acceleration and
deceleration.
R Have all maintenance work performed at
the intervals specified in the Maintenance
Booklet and as required by the
Maintenance system. Contact an
authorized Mercedes-Benz Center.
Fuel consumption is also increased by driving
in cold weather, in stop-and-go traffic, on
short trips and in mountainous areas.
Drinking and driving
GWarning!
Drinking and driving and/or taking drugs and
driving are very dangerous combinations.
Even a small amount of alcohol or drugs can
affect your reflexes, perceptions and
judgment.
The possibility of a serious or even fatal
accident are greatly increased when you drink
or take drugs and drive.
Do not drink or take drugs and drive or allow
anyone to drive who has been drinking or
taking drugs.
Pedals
GWarning!
Make sure absolutely no objects are
obstructing the pedals’ range of movement.
Keep the driver’s footwell clear of all
obstacles. If there are any floormats or
carpets in the footwell, make sure that the
pedals still have sufficient clearance.
During sudden driving or braking maneuvers,
the objects could get caught between the
pedals. You could then no longer brake or
accelerate. This could lead to accidents and
injury.
Power assistance
GWarning!
There is no power assistance for the steering
and the brake when the engine is not running.
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Steering and braking requires significantly
more effort and you could lose control of the
vehicle and cause an accident as a result.
Do not turn off the engine while the vehicle is
in motion.
Brakes
Downhill grades
! When driving down long and steep
grades, relieve the load on the brakes by
shifting into a lower gear to use the
engine’s braking power. This helps prevent
overheating of the brakes and reduces
wear.
When using the engine’s braking power, a
drive wheel may not spin for an extended
period of time, e.g. on slippery road
surfaces. This may cause serious damage
to the drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
Continuous or hard braking
GWarning!
Resting your foot on the brake pedal will
cause excessive and premature wear of the
brake pads.
It can also result in the brakes overheating,
thereby significantly reducing their
effectiveness. It may not be possible to stop
the vehicle in sufficient time to avoid an
accident.
After hard braking, it is advisable to drive on
for some time, rather than immediately park,
so that the air stream will cool down the
brakes faster.
Wet roads
GWarning!
After driving in heavy rain for some time
without applying the brakes or through water
deep enough to wet brake components, the
first braking action may be somewhat
reduced and increased pedal pressure may be
necessary to obtain expected brake effect.
Maintain a safe distance from vehicles in
front.
To help prevent brake disk corrosion after
driving on wet or salt-covered roads, it is
advisable to brake the vehicle with
considerable force prior to parking. The heat
generated serves to dry the brakes.
Salt-covered roadsGWarning!
A layer of salt on the brake discs and the brake
linings may cause a delay in the braking
effect, resulting in a significantly increased
braking distance, which could lead to an
accident.
To avoid this danger, you should:
R occasionally brake carefully when you are
driving on salt-covered roads, so that any
layer of salt that may have built up on the
brake discs and the brake linings is
removed without putting other road users
at risk
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
Brake service
! The brake fluid level in the reservoir may
be too low if the brake warning lamp in the
instrument cluster comes on and an
acoustic warning sounds although the
parking brake is released. Observe
additional messages in the multifunction
display that may appear.
Brake pad wear or a leak in the system may
be the reason for low brake fluid in the
reservoir.
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Have the brake system inspected
immediately. Contact an authorized
Mercedes-Benz Center.
All checks and service work on the brake
system should be carried out by qualified
technicians only. Contact an authorized
Mercedes-Benz Center.
Only install brake pads and use brake fluid
recommended by Mercedes-Benz.GWarning!
If other than recommended brake pads are
installed, or other than recommended brake
fluid is used, the braking properties of the
vehicle can be degraded to an extent that safe
braking is substantially impaired. This could
result in an accident.
! 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 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
position 0 or 1 or KEYLESS-GO start/stop
button in position 0 or 1) when the parking
brake is being tested on a brake test
dynamometer. 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.
If your brake system is only subjected to
moderate loads, you should occasionally test
the effectiveness of the brakes by applying
above-normal braking pressure at higher
speeds. This will also enhance the grip of the
brake pads.
GWarning!
Make sure not to endanger any other road
users when carrying out these braking
maneuvers.
Refer to the description of the Brake Assist
System (BAS) ( Y page 63).
Parking brake
When driving on wet roads or dirt covered
surfaces, road salt and/or dirt can get into
the parking brake.
To prevent corrosion and a reduction in the
braking power of the parking brake, observe
the following:
XFrom time to time, lightly engage the
parking brake before driving off.XDrive a distance of approximately 110 yds
(100 m) at a maximum speed of 12 mph
(20 km/h).GWarning!
While performing this procedure please
assure that the vehicle is stopped before
applying the parking brake. Otherwise the
rear wheels could lock up. You could lose
control of the vehicle and cause an accident.
In addition, the vehicle’s brake lights do not
light up when the parking brake is engaged.
Make sure not to endanger any other road
users when you engage the parking brake.
Driving off
Warm up the engine smoothly. Do not place
full load on the engine until the operating
temperature has been reached.
! When driving off on a slippery surface, do
not allow a drive wheel to spin for an
extended period with the ESP ®
switched
off. Doing so may cause serious damage to
the drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
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! Simultaneously depressing the
accelerator pedal and applying the brakes
reduces engine performance and causes
premature brake and drivetrain wear which
is not covered by the Mercedes-Benz
Limited Warranty.
Hydroplaning
Depending on the depth of the water layer on
the road, hydroplaning may occur, even at low
speeds and with new tires. In heavy rain or
when conditions indicate possible
hydroplaning:
XReduce vehicle speed.XAvoid track grooves in the road.XApply brakes cautiously.
Standing water
! Do not drive through flooded areas.
Before driving through water, determine its
depth.
If you must drive through standing water,
drive slowly to prevent water from entering
the passenger compartment or the engine
compartment. Water in these areas could
cause damage to electrical components or
wiring of the engine or transmission, or
could result in water being ingested by the
engine through the air intake causing
severe internal engine damage. Any such
damage is not covered by the Mercedes-
Benz Limited Warranty.
i Select the raised level ( Y page 159)
before driving through standing water.
For more information, see “Driving through
water” ( Y page 266).
Off-road drivingGWarning!
Do not load items on the crossbars. It may
cause instability during some maneuvers
which could result in an accident.
Drive slowly in unknown terrain. This will
make it easier to recognize unexpected
obstacles and avoid damage to the vehicle.
To help avoid the vehicle rolling over, never
turn it around on steep inclines. If the vehicle
cannot complete the attempted climb, back it
down in reverse gear.
Do not drive along the side of a slope. The
vehicle might otherwise rollover. If in doing so
the vehicle begins to show a tendency to roll,
immediately steer into a line of gravity
(straight up or downhill).
Never let the vehicle roll backwards in idle.
You may lose control of the vehicle if you use
only the service brake. For information on
driving downhill, see “Driving downhill”.
GWarning!
Sand, dirt, mud and other material having
friction property can cause exceptional wear
and tear as well as brake failure.
Have the brakes checked for dirt build-up and
cleaned. There is otherwise a risk that full
braking power may not be available in an
emergency.
GWarning!
Please be aware that by raising the vehicle
level, the center of gravity also rises.
Therefore, always ensure that the vehicle
level is as low as possible. With higher ride
height the ESP ®
may activate earlier in certain
situations.
Read this chapter carefully before you begin
off-road travel.
Familiarize yourself with the vehicle
characteristics and gear changing before you
attempt any difficult terrain off-road driving.
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We recommend that you start out with easy
off-road travel.
Special driving features for off-road
driving
The following driving features are available for
specific kind of operation:
R Off-road ABS ( Y page 63)
R Off-road ESP ®
(Y page 65)
R Off-road 4-ETS ( Y page 64)
R Hill-start assist system ( Y page 117)
R LOW RANGE mode ( Y page 120)
R Differential locks ( Y page 121)
R Downhill Speed Regulation (DSR)
( Y page 155)
R Off-road driving program (Vehicles without
enhanced off-road package) ( Y page 158)
R Air suspension program ( Y page 159)
Off-road driving rules
R Engage the off-road driving program
( Y page 158) or LOW RANGE mode
( Y page 120) before driving under off-road
conditions.
R If necessary, activate differential locks
( Y page 121).
R Make sure you select a vehicle level
( Y page 159) appropriate to the
topographical conditions. Always make
sure the vehicle has enough ground
clearance.
R Fasten items being carried as securely as
possible ( Y page 194).
R Always navigate gradients with the engine
on and with the transmission engaged in a
gear. Switch on the DSR ( Y page 155) to
help maintain a preset speed.
! Observe the following during off-road
driving:
R Keep doors, tailgate, windows, and tilt/
sliding sunroof closed whenever driving
off-road.
R Adjust vehicle speed to condition of
terrain. The more uneven, rutty and
steeper the terrain, the lower the speed
should be. Drive through water slowly at
an even speed, avoiding a bow wave.
R Be especially careful when driving in
unknown territory. It may be necessary
to get out of the vehicle and scout the
path you intend to take.
R Watch out for obstacles, such as rocks,
holes, tree stumps and ruts.
R Before driving through water, determine
its depth.
R Do not stop vehicle while immersed in
water, and do not shut off the engine.
R In sandy soil, drive at a steady speed as
allowed by conditions. This helps
overcome the vehicle rolling resistance
and reduces the likelihood of the vehicle
sinking into the ground.
R Do not initiate jumps with the vehicle. It
interrupts the forward momentum of the
vehicle.
R Always drive onto slopes with the engine
running and the vehicle in gear.
R Do not shift automatic transmission into
neutral position N.GWarning!
Do not reduce the tire inflation pressure
before driving through sand. However, if you
do so, remember to correct the tire inflation
pressure before continuing your trip. Driving
with reduced tire inflation pressure increases
the risk of losing control of the vehicle and
rolling over.
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Checklist before off-road driving
Engine oil level
RCheck the engine oil level (Y page 230).
Only with a proper oil level can the vehicle
obtain a trouble-free oil supply, even on
steep gradients.
! If the engine oil level warning lamp comes
on while driving, stop the vehicle in a safe
location or as soon at is safe to do so.
Check the engine oil level.
The engine oil level warnings should not be
ignored. Extended driving with the symbol
displayed could result in serious engine
damage that is not covered by the
Mercedes-Benz Limited Warranty.
Tires
RCheck the tread depth and maintain
specified tire inflation pressure. A placard
with the recommended tire inflation
pressures is located on the driver’s door B-
pillar (Y page 243).
RCheck tires for possible damage and
remove foreign objects.
RReplace missing valve caps.
Rims
RDented or bent rims can cause tire inflation
pressure loss and damage the tire beads.
For this reason, check and, if necessary,
change rims before driving off-road.
Vehicle tool kit
RCheck if the jack (Y page 286) is
functional.
RAlways take the vehicle tool kit, a strong
tow rope, a shovel and a small plank (to put
under the jack on sandy soil) with you.
Driving in steep terrain
Slope angle
:Overhang angle, front;Overhang angle, rearVehicles
with air
suspension
program
:
GL 450,
GL 350
BlueTEC
:
GL
550
;
all
models
Raised level31°32°26°Highway26°27°21°Vehicles
with
enhanced
off-road
package
:
GL 450,
GL 350
BlueTEC
:
GL
550
;
all
models
Off-road
level 3
32°33°27°Off-road
level 2
31°32°26°Off-road
level 1
28°28°23°Highway26°27°21°
RComply with the warnings (Y page 262) and
rules for off-road driving (Y page 263).
RDriving on embankments, slopes and other
steep inclines should only be done straight
up or downhill, i.e. in the line of gravity.
Maximum vehicle climbing ability is a
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100% grade which is equivalent to a slope
angle of 45°. Keep in mind that the
climbing ability of the vehicle depends on
terrain conditions.
R Shift automatic transmission into gear
range 1 (Y page 118).
R Drive slowly.
R Avoid excessive engine speeds – drive with
moderate engine speeds (max. 3 000 rpm).
R Utilize the engine’s braking power when
descending a slope, observe the engine
speed (do not overrev the engine). Apply
the service brake as needed.
i For maximum engine speed, see
“Tachometer” (Y page 125) and see vehicle
specification for your vehicle
( Y page 362).
R Check the brakes after a lengthy
downgrade drive.GWarning!
Never turn the vehicle around on steep
inclines. The vehicle might roll over. If the
vehicle cannot complete the attempted climb,
back it down in reverse gear.
i The hill-start assist system supports you
when driving uphill.
For more information, see “Hill-start assist
system” ( Y page 155).
Traction in steep terrain
The maximum vehicle climbing ability is a
100% grade which is equivalent to a slope
angle of 45°. Keep in mind that the climbing
ability of the vehicle depends on terrain
conditions.
Be easy on the accelerator and watch for
continuous wheel traction when driving in
steep terrain.
i The 4-ETS helps greatly when starting out
on a steep incline when the front wheels
have then the tendency to slip due to the
weight shifting towards the rear axle.
The 4-ETS recognizes the situation and
limits the torque for the front wheels by
braking them.
Simultaneously the torque for the rear
wheels is increased.
i Vehicles with enhanced off-road package
are equipped with automatic locks for the
center and rear axle differential to improve
vehicle traction.
Driving across a hilltop
Decelerate just ahead of a hilltop (do not shift
automatic transmission into neutral position
N ), to prevent the vehicle from speeding up
too much after climbing a hill.
Use the momentum of the vehicle to drive
across the hilltop.
After climbing a hill, driving in this manner
prevents the vehicle from:
R losing ground contact when cresting hills
R losing its forward momentum
R speeding up too much after climbing the hill
Driving downhill
R Drive slowly.
R Do not drive at an angle to the incline. Steer
into the line of gravity and drive with the
front wheels pointing straight downhill.
Otherwise, the vehicle may slide sideways
off the path and roll over.
R Shift automatic transmission into gear
range 1 (Y page 118).
R On steep inclines, use the Downhill Speed
Regulation ( Y page 155).
R Utilize the engine’s braking power to
reduce vehicle speed.
If this is insufficient, apply the brakes
gently. Make sure the vehicle is moving in
the line of gravity.
R Check the brakes after a lengthy
downgrade drive.
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iThe special Off-road ABS (Y page 63)
setting allows for precise and brief
(cyclical) blocking of the front wheels,
permitting them to dig into loose ground.
Remember that, when stopped, the front
wheels slide across a surface and thus lose
their ability to steer the vehicle.
Driving through water
:Fording depthVehicles with air
suspension
program (raised
level)
:20 in (50 cm)Vehicles with
enhanced off-road
package
:Off-road level 120 in (50 cm)Off-road level 220 in (50 cm)Off-road level 323.6 in (60 cm)
RBefore driving through water, determine its
depth.
! The water depth must not exceed the
respective value listed in the table. The
ground under the water might not be firm
which could result the water being deeper
than expected when driving the vehicle
through it. Please note that the water level
is correspondingly lower for flowing water.
RSelect the highest vehicle level possible
(Y page 159).
RSwitch to off-road driving program
(Y page 158) or LOW RANGE mode
(Y page 120) before driving through water.
RShift automatic transmission into gear
range 1 or 2 (Y page 118).
RAvoid high engine speeds.
REnter and leave the water only at a shallow
spot, driving at walking speed.
! Never accelerate before driving into the
water. The bow wave could force water into
the engine and auxiliary equipment, thus
damaging them.
RDrive through the water slowly and at a
constant speed.
RDo not stop vehicle while immersed in
water, and do not shut off the engine.
! Do not open any of the vehicle’s doors
while driving through water. Water could
otherwise enter the vehicle interior and
damage the vehicle’s electronics, as well as
the interior equipment.
RThere is a very high level of driving
resistance in water. The surface is slippery
and may not be firm, making pulling away
in water difficult and dangerous.
RMake sure that only small bow waves are
formed when driving the vehicle through
water.
RClean mud off the tire tread after driving
through water.
RTo dry the brakes, apply pressure to the
brake pedal several times while driving
after leaving the water.
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Crossing obstacles
! Obstacles can damage the vehicle
underbody or suspension components. If
possible use the assistance of a second
person outside the vehicle to scout the
path you intend to take and check for
adequate ground clearance when you cross
obstacles with your vehicle. The person
assisting you outside the vehicle should
always be a safe distance away from the
vehicle and positioned so that he or she
cannot get hurt in case of any unexpected
vehicle movement.
After off-road driving or crossing obstacles,
inspect vehicle for any damage, especially
vehicle underbody and suspension
components. Failure to do so can adversely
affect the vehicle’s future performance,
including increased chance of an accident.
When driving over tree stumps, big rocks and
other obstacles, observe the following rules:
RMake sure the off-road driving program
(Y page 158) or if equipped the
LOW RANGE mode (Y page 120) is
switched on.
RAvoid high engine speeds.
RShift automatic transmission into gear
range 1 (Y page 118).
RCheck the vehicle clearance before
crossing obstacles.
RCross obstacles (e.g. tree stumps or big
rocks) very slowly by aiming one of the front
wheels at the center of the obstacle, and
repeat same with the rear wheel.
! Special attention is needed when you
cross obstacles on a steep incline.
The vehicle could slide sideways as a result
of its possible slanted position which in turn
may result in the vehicle tipping or rolling
over.
Driving on sand
GWarning!
Do not reduce the tire inflation pressure
before driving through sand. However, if you
do so, remember to correct the tire inflation
pressure before continuing your trip. Driving
with reduced tire inflation pressure increases
the risk of losing control of the vehicle and
rolling over.
When driving on sand, observe the following
rules:RSet the raised level (Y page 159).
RAvoid high engine speeds.
RShift automatic transmission into a gear
range that is appropriate for the terrain.
RIn sandy soil, drive at a steady speed as
conditions permit. This helps overcome the
vehicle rolling resistance and reduce the
likelihood of the vehicle sinking into the
ground.
RDrive in tracks of other vehicles if they are
not too deep and you have sufficient
clearance.
Ruts
A number of off-road tracks or other byways
have deep ruts which can cause the
underbody to come in contact with the
ground.
RMake sure the off-road driving program
(Y page 158) or, if equipped, the
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LOW RANGE mode (Y page 120) is
switched on.
R Set the raised level ( Y page 159).
! Check that the ruts are not too deep and
your vehicle’s clearance is sufficient.
Otherwise:
R your vehicle may be damaged
R the underbody of the vehicle may come
in contact with the ground and you may
get stuck
R Avoid high engine speeds.
R Shift automatic transmission into gear
range 1 (Y page 118).
R Drive next to the ruts rather than through
them if at all possible.
R If the ruts are too deep to drive in, drive with
one side of the vehicle on the grassy center
strip if the route permits.
Returning from off-road driving GWarning!
If you feel a sudden significant vibration or
ride disturbance, or you suspect that possible
damage to your vehicle has occurred, you
should turn on the hazard warning flashers,
carefully slow down, and drive with caution to
an area which is a safe distance from the road.
Inspect the tires and the vehicle underbody
for possible damage. If the vehicle or tires
appear unsafe, have the vehicle towed to the
nearest authorized Mercedes-Benz Center or
tire dealer for repairs.
Off-road driving increases strain on the
vehicle.
We recommend that you inspect the vehicle
for possible damage after each off-road trip.
Recognizing any damage and a subsequent
timely repair reduces the chance of a possible
breakdown or accident later on.
Proceed as follows:
R Switch off the off-road driving program
( Y page 158) or the LOW RANGE mode
( Y page 120).
R Switch off the DSR ( Y page 156).
R Set the differential locks to AUTO
( Y page 122).
R Lower the vehicle back to a level suitable
for road conditions, e.g. highway/high-
speed level ( Y page 159).
R Clean all exterior lamps and check for
possible damage.
R Clean the front and rear license plate.
R Remove excessive dirt from tires, wheels,
wheel housings, and underbody.
For instance, after driving in mud, clean the
radiator, chassis, engine, brakes, and
wheels from extreme dirt using a strong jet
of water.
R Check tires for possible damage.
R Inspect vehicle underbody, oil pan, brake
hoses, etc., as well as vehicle underbody
for possible damage.
R Check for brush or branches caught in the
underbody.
! Brush or branches could increase the
possibility of a fire, as well as cut fuel and/
or brake lines, puncture rubber bellows of
the axles or drive shafts.
R After continued operation in mud, sand,
water or other dirty conditions clean the
brake discs, wheels, brake pads and check
and clean axle joints.
R Conduct a brake test.268Driving instructionsOperation
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