
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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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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XClearing the maintenance service
indicator message manually: Press reset
button : on the instrument cluster.
The standard display appears in the
multifunction display.
Maintenance service term exceeded
If you have exceeded the suggested
maintenance service term, you will see the
following message in the multifunction
display:
Service A Exceeded By XXXXX Miles
(Km)
Service A Exceeded By XXX Days
Service A Exceeded By X Day
In addition, a signal sounds when the
message appears.
Any authorized Mercedes-Benz Center will
reset the maintenance service indicator
following a completed maintenance service.
Calling up the maintenance service
indicator display
iThe menu overview can be found on
(Y page 127).
You can call up the maintenance service
indicator display at any time to check when
the next maintenance service is required.
XSwitch on the ignition.XPress button V or U on the
multifunction steering wheel repeatedly
until the standard display (Y page 128)
appears in the multifunction display.
XPress button * or & on the
multifunction steering wheel until the
maintenance service indicator display with
the service symbol ¯ and the
maintenance service deadline appears in
the multifunction display.
iIf the battery was disconnected, the days
of disconnection will not be included in the
count shown by the maintenance service
indicator. To arrive at the true maintenance
service deadline, you will need to subtract
these days from the days shown in the
maintenance service indicator message or
maintenance service indicator display.
Do not confuse the maintenance service
indicator with the engine oil level indicator
4.
Resetting the maintenance service
indicator
In the event that the maintenance service on
your vehicle is not carried out at an authorized
Mercedes-Benz Center, you can have the
maintenance service indicator reset.
The automotive maintenance facility carrying
out the maintenance service will find the
information for resetting the maintenance
service indicator in the maintenance-relevant
literature for your vehicle.
Such literature is available at any authorized
Mercedes-Benz Center or directly from
Mercedes-Benz.
! If the maintenance service indicator was
reset inadvertently, have an authorized
Mercedes-Benz Center correct it.
Only reset the maintenance service
indicator if the proper maintenance service
has been performed. Not following the
proper maintenance service as described
in the Maintenance Booklet will result in
engine damage and/or other vehicle
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Display messagesPossible causes/consequences and M Solutions#The battery is no longer charging.
Possible causes:
R alternator malfunctioning
R broken poly-V-belt
R a malfunction in the electronic systemXStop immediately in a safe location or as soon as it is safe
to do so and check the poly-V-belt.XIf it is broken: Do not continue to drive. Otherwise the
engine will overheat due to an inoperative water pump
which may result in damage to the engine. Contact an
authorized Mercedes-Benz Center.XIf it is intact: Drive to the nearest authorized Mercedes-
Benz Center immediately. Adjust driving to be consistent
with reduced braking responsiveness.#Battery/
Alternator
Stop
VehicleThe battery is defective.XStop the vehicle in a safe location or as soon as it is safe
to do so.XEngage the parking brake.XDo not continue to drive.XContact an authorized Mercedes-Benz Center.4Check
engine
oil level
at next
refueling.The engine oil level is too low.XCheck the engine oil level ( Y page 230) and add engine oil
as required ( Y page 231).XIf you must add engine oil frequently, have the engine
checked for possible leaks.If the message Check engine oil level
at next refueling. appears while the
engine is running and at operating
temperature, the engine oil level has dropped
to approximately the minimum level.
The message will be stored in the vehicle
status message memory after you have
cleared it from the multifunction display.
Visually check for oil leaks. If there are no
obvious oil leaks, drive to the nearest service
station to refill your engine oil to the required
level.For information on approved engine oils
contact an authorized Mercedes-Benz Center
or visit www.mbusa.com (USA only).
! 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.308Vehicle status messages in the multifunction displayPractical hints
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If the antifreeze mixture is effective to -35‡
(-37† ), the boiling point of the coolant in the
pressurized cooling system is reached at
approximately 266‡ (130†).
The coolant solution must be used year round
to provide the necessary corrosion protection
and increase boil-over protection. Refer to
the Maintenance Booklet for replacement
interval.
Coolant system design and coolant used
determine the replacement interval. The
replacement interval published in the
Maintenance Booklet is only applicable if
MB 325.0 Anticorrosion/Antifreeze solution
or other Mercedes-Benz approved products
of equal specification are used to renew the
coolant concentration or bring it back up to
the proper level.
For information on other Mercedes-Benz
approved products of equal specification,
contact an authorized Mercedes-Benz Center
or visit www.mbusa.com (USA only).
To provide important corrosion protection,
the solution must be at least 50%
anticorrosion/antifreeze (equivalent to
freeze protection to approximately -35‡
[-37†]).
If you use a solution that is more than 55%
anticorrosion/antifreeze (freeze protection
to approximately -49‡ [-45†]), the engine
temperature will increase due to the lower
heat transfer capability of the solution.
Therefore, do not use more than this amount
of anticorrosion/antifreeze.If the coolant level is low, water and MB 325.0
Anticorrosion/Antifreeze should be used to
bring it up to the proper level (have cooling
system checked for signs of leakage). Please
make sure the mixture is in accordance with
label instructions.
The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water.
If you are not sure about the water quality,
contact an authorized Mercedes-Benz
Center.
Anticorrosion/antifreeze
Your vehicle contains a number of aluminum
parts. The use of aluminum components in
motor vehicle engines necessitates that
anticorrosion/antifreeze coolant used in
such engines be specifically formulated to
protect the aluminum parts. Failure to use
such anticorrosion/antifreeze coolant will
result in a significantly shortened service life.
Therefore, the following product is strongly
recommended for use in your vehicle:
MB 325.0 Anticorrosion/Antifreeze agent.
Before the start of the winter season (or once
a year in hot southern regions), you should
have the anticorrosion/antifreeze
concentration checked.
The coolant is also regularly checked each
time you bring your vehicle to an authorized
Mercedes-Benz Center for service.
ModelApproximate freeze protection-35‡ (-37†)-49‡ (-45†)Cooling systemGL 350 BlueTEC5.0 US qt (4.75 l)5.5 US qt (5.2 l)GL 450
GL 5506.3 US qt (6.0 l)7.0 US qt (6.6 l)374Fuels, coolants, lubricants, etc.Technical data
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