2010 MERCEDES-BENZ GL450 air suspension

For more information, see “Washer system
and headlamp cleaning system”
(Y page 370).
Brake fluid level
! If you find that the brake fluid in the brake
fluid reservoir has fallen to the minimum
mark or below, have the brake system
checked for brake pad thickness and leaks
immediately. Contact an authorized
Mercedes-Benz Center immediately. Do
not add brake fluid as this will not solve the
problem. For more information, see
“Practical hints”.
When checking the brake fluid level, the
vehicle must be parked on level ground.
The brake fluid level is correct when it is
between lower mark (MIN) ; and upper
mark (MAX) : of the brake fluid reservoir.
Tires and wheels
Safety notes
Contact an authorized Mercedes-Benz Center
for information on tested and recommended
rims and tires for summer and winter
operation. They can also offer advice
concerning tire service and purchase.
GWarning!
Replace rims or tires with the same
designation, manufacturer and type as shown
on the original part. For further information
contact an authorized Mercedes-Benz Center.
If incorrectly sized rims and tires are
mounted, the wheel brakes or suspension
components can be damaged. Also, the
operating clearance of the wheels and the
tires may no longer be correct.
GWarning!
Worn, old tires can cause accidents. If the tire
tread is worn to minimum tread depth, or if
the tires have sustained damage, replace
them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can result
in the bolts loosening and possibly an
accident.
Retreaded tires are not tested or
recommended by Mercedes-Benz, since
previous damage cannot always be
recognized on retreads. The operating safety
of the vehicle cannot be assured when such
tires are used.
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.
GWarning!
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
could lose control of the vehicle. Continued
driving with a flat tire or driving at high speed
with a flat tire will cause excessive heat build-
up and possibly a fire.
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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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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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Safety systemsDisplay messagesPossible causes/consequences and M SolutionsGTele Aid
Inoperativ
eOne or more main functions of the Tele Aid system are
malfunctioning.XHave the Tele Aid system checked at an authorized
Mercedes-Benz Center.+Restraint
Sys.
Malfunctio
n
Service
RequiredThe system is malfunctioning.XDrive with added caution to the nearest authorized
Mercedes-Benz Center and have the system checked
immediately.GWarning!
In the event a malfunction of the SRS is
indicated as outlined above, the SRS may not
be operational.
For your safety, we strongly recommend that
you contact an authorized Mercedes-Benz
Center immediately to have the system
checked. Otherwise the SRS may not be
activated when needed in an accident, which
could result in serious or fatal injury, or it
might deploy unexpectedly and unnecessarily
which could also result in injury.
Driving systems
Display messagesPossible causes/consequences and M SolutionsÁLevel
Selection
Not
PermittedThe selected vehicle level cannot be adjusted, because
R you are driving too fast for the desired vehicle level
R you are towing a trailer
R you are using accessories that are connected to the trailer
power socket, e.g. a bicycle rackXReduce vehicle speed and set the desired vehicle level
again ( Y page 159).XObserve the notes on trailer towing ( Y page 269).ÁMalfunctio
nThe air suspension is malfunctioning.XDo not drive faster than 50 mph (80 km/h).XHave the system checked at an authorized Mercedes-Benz
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Rear wiper bladeXInsert wiper blade ; into wiper arm :.XHold wiper arm : and engage wiper
blade ; by pushing it in direction of arrow
until it locks into place.
XCheck whether the wiper blade is securely
fastened.
XFold wiper arm : to rest on the rear
window.
Make sure to hold on to the wiper when
folding the wiper arm back.
! Make sure the wiper blade is installed
properly. An improperly installed wiper
blade may cause rear window damage.
Flat tire
Safety notes
Your vehicle may be equipped with an
MOExtended system or a Minispare wheel.
Vehicles with an MOExtended system do not
have a spare wheel or a TIREFIT kit.
For information on your vehicle’s equipment,
see “Rims and tires” (Y page 365).
GWarning!
The dimensions of the spare wheel are
different from those of the road wheels. As a
result, the vehicle handling characteristics
change when driving with a spare wheel
mounted. Adapt your driving style
accordingly.
The spare wheel is for temporary use only.
When driving with a spare wheel mounted,
ensure proper tire inflation pressure and do
not exceed a vehicle speed of 50 mph
(80 km/h).
Contact the nearest authorized Mercedes-
Benz Center as soon as possible to have the
spare wheel replaced with a regular road
wheel.
Never operate the vehicle with more than one
spare wheel mounted.
Do not switch off the ESP® when a spare
wheel is mounted.
GWarning!
Your vehicle is equipped with air suspension
program. Do not open or close any doors or
the tailgate while mounting a spare wheel. The
vehicle could rise or lower to a previously
selected level. You or others could be injured
as a result.
Preparing the vehicle
XMake sure the vehicle level is set to
highway level (Y page 159).
XWhenever possible, park the vehicle in a
safe distance from moving traffic on a hard,
flat surface.
XTurn on the hazard warning flasher.XTurn the steering wheel so that the front
wheels are in a straight-ahead position.
XEngage the parking brake.XShift the automatic transmission into park
position P.
XTurn off the engine.XRemove the SmartKey from the starter
switch.
or
XVehicles with KEYLESS-GO: Open the
driver’s door (this puts the starter switch in
position 0, same as with the SmartKey
removed from the starter switch). The
driver’s door can then be closed again.
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