
radio, and heater, to the extent that these
items are available as factory-installed
equipment (whether installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire. Air
pressure is expressed in pounds per square
inch (psi), kilopascal (kPa), or bar.
Aspect ratio
Dimensional relationship between tire
section height and section width expressed
in percentage.
Bar
Metric unit for air pressure. There are
14.5038 pounds per square inch (psi) to
1 bar; there are 100 kilopascals (kPa) to 1 bar.
Bead
The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle has
been sitting for at least 3 hours or driven no
more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with standard
equipment including the maximum capacity
of fuel, oil, and coolant, and, if so equipped,
air conditioning and additional optional
equipment, but without passengers and
cargo.
DOT (Department of Transportation)
A tire branding symbol which denotes the tire
meets requirements of the U.S. Department
of Transportation.
GAWR (Gross Axle Weight Rating)
The GAWR is the maximum permissible axle
weight. The gross vehicle weight on each axle
must never exceed the GAWR for the front
and rear axle indicated on the certification
label located on the driver’s door B-pillar.
GTW (Gross Trailer Weight)
The GTW is the weight of the trailer plus the
weight of all cargo, equipment, luggage etc.
loaded on the trailer.
GVW (Gross Vehicle Weight)
The GVW comprises the weight of the vehicle
including fuel, tools, spare wheel, installed
accessories, passengers and cargo and, if
applicable, trailer tongue load. The GVW must
never exceed the GVWR indicated on the
certification label located on the driver’s door
B-pillar.
GVWR (Gross Vehicle Weight Rating)
This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the vehicle including all options, passengers,
fuel, and cargo and, if applicable, trailer
tongue load). It is indicated on the
certification label located on the driver’s door
B-pillar.
Kilopascal (kPa)
Metric unit for air pressure. There are 6.9 kPa
to 1 psi; another metric unit for air pressure
is bar. There are 100 kilopascals (kPa) to
1 bar.
Load index
Numerical code associated with the
maximum load a tire can support.
Maximum load rating
The maximum load in kilograms and pounds
that can be carried by the tire.
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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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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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XFold the wiper arms forward until they snap
into place.XClean the windshield and the wiper blade
inserts with a clean cloth and mild
detergent solution.XUse a soft, clean cloth and a mild window
cleaning solution on all outside and inside
glass surfaces.
An automotive glass cleaner is
recommended.
! Fold the windshield wiper arms back onto
the windshield before turning the SmartKey
in the starter switch or pressing the
KEYLESS-GO start/stop button.
Hold on to the wiper when folding the wiper
arm back. If released, the force of the
impact from the tensioning spring could
crack the windshield.
! To clean the window interior, do not use
a dry cloth, abrasives, solvents or cleaners
containing solvents. Do not touch the
inside of the windows with hard objects
such as an ice scraper or ring. Doing so may
damage the windows.
Light alloy wheels
If possible, clean wheels once a week.
XUse Mercedes-Benz approved Wheel Care,
a soft bristle brush and a strong spray of
water for cleaning the light alloy wheels.
! Only use acid-free cleaning materials.
Acid may cause corrosion or damage the
clear coat.
! The vehicle should not be parked for an
extended period of time immediately after
it has been cleaned. This applies especially
after the wheel rims have been cleaned
with wheel rim cleaner. Wheel rim cleaners
can lead to increased corrosion of the
brake disks and brake pads. Non-approved
wheel cleaners may also damage the wheel
paint if the vehicle is not driven after
cleaning.
Therefore, the vehicle’s brake system
should always be warmed-up before it is
parked after cleaning. Drive your vehicle for
several minutes to allow the brakes to dry.
When applying Mercedes-Benz approved
Tire Care and Mercedes-Benz approved
Wheel Care products, take care not to
spray them on the brake disks.
Plastic and rubber partsXUse a gentle dishwashing detergent or mild
detergent for delicate fabrics as a washing
solution.XWipe with a cloth moistened in a lukewarm
solution.
The surface may temporarily change color.
If this is the case, wait for it to dry.GWarning!
Do not use cleaners or cockpit care sprays
containing solvents to clean the cockpit or the
steering wheel. Cleaners containing solvents
will make the surface porous and vehicle
occupants could suffer serious injuries from
plastic parts coming loose in the event of air
bag deployment.
! Do not use oil, wax or scouring agents.
Otherwise you may scratch or damage the
surface.
Hard plastic trim items
XUse Mercedes-Benz approved Interior Care
on a soft, lint-free cloth and apply with light
pressure.
COMAND display
! You must switch off the COMAND display
and allow it to cool prior to cleaning.
! Do not use any liquids or cleaning agents.
These can damage or even destroy the
COMAND display screen.
XUse a standard microfiber cloth and apply
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TBA can be used provided the ratio of any one
of these oxygenates to gasoline does not
exceed 10%; MTBE must not exceed 15%.
The ratio of methanol to gasoline must not
exceed 3% plus additional cosolvents.
Using mixtures of ethanol and methanol is not
allowed. Gasohol, which contains 10%
ethanol and 90% unleaded gasoline, can be
used.
These blends must also meet all other fuel
requirements, such as resistance to spark
knock, boiling range, vapor pressure, etc.
Diesel engine
Only use commercially available vehicular
ULTRA-LOW SULFUR HIGHWAY DIESEL FUEL
(ULSD, 15 ppm SULFUR MAXIMUM) that
meets the ASTM D975 standard. Failure to
use ULTRA-LOW SULFUR HIGHWAY DIESEL
FUEL (ULSD) can severely damage the
vehicle’s exhaust after-treatment device.
To prevent malfunctions, diesel fuel with
improved cold flow characteristics is offered
in the winter months. Check with your fuel
retailer.
! Do not fill the tank with gasoline. Do not
blend diesel fuel with gasoline or kerosene.
The fuel system and engine will otherwise
be damaged, which is not covered by the
Mercedes-Benz Limited Warranty.
For further information on diesel fuel pump
labeling, contact an authorized Mercedes-
Benz Center or visit www.mbusa.com (USA
only).
Biodiesel (FAME = Fatty Acid Methyl
Ester) containing fuels
Mercedes-Benz USA approves the use of B5
(standard ULSD which may contain a
maximum of 5% biodiesel) in all Common-rail
injection (CDI) and BlueTEC diesel engines.
Diesel fuels containing a higher percentage of
biodiesel, e.g. B20, as well as straight
biodiesel may cause severe damage to your
engine/fuel system and are not approved.
Please ask your service station personnel for
further information. If the B5 biodiesel blend
is not sufficiently labeled to clearly indicate
that it meets the ULSD standard, please do
not use it.
The Mercedes-Benz Limited Warranty does
not cover damages caused by the use of fuels
not meeting Mercedes-Benz approved fuel
standards.
Gasoline additives (gasoline engine)
A major concern among engine
manufacturers is carbon build-up caused by
gasoline. Mercedes-Benz recommends only
the use of quality gasoline containing
additives that prevent the build-up of carbon
deposits.
After an extended period of using fuels
without such additives carbon deposits can
build up, especially on the intake valves and
in the combustion area, leading to engine
performance problems such as:
R Warm-up hesitation
R Unstable idle
R Knocking/pinging
R Misfire
R Power loss
In areas where carbon deposits may be
encountered due to lack of availability of
gasoline which contains these additives, the
use of Mercedes-Benz approved additives is
recommended.
Contact an authorized Mercedes-Benz Center
or visit www.mbusa.com (USA only) for a
listing of approved products. Follow
directions on the product label.
Do not blend other fuel additives with fuel.
This only results in unnecessary cost and may
be harmful to the engine operation.
! Damage or malfunction resulting from
poor fuel quality or from blending additional
fuel additives other than those tested and
approved by us for use on Mercedes-Benz
372Fuels, coolants, lubricants, etc.Technical data
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