
recognize dangers in time, cause an accident
and injure yourself and others.
Collision warning
If a vehicle is detected in the monitoring range
of Blind Spot Assist and you switch on the turn
signal, a double warning tone sounds. Red
warning lamp : flashes. If the turn signal
remains on, detected vehicles are indicated
by the flashing of red warning lamp :. There
are no further warning tones.
Switching on Blind Spot Assist
XMake sure that the radar sensor system
( Y page 224) and Blind Spot Assist
( Y page 226) are activated in the on-board
computer.XTurn the key to position 2 in the ignition
lock.
Warning lamps : light up red in the
exterior mirrors for approximately 1.5
seconds and then turn yellow.
Towing a trailer
When you attach a trailer, make sure you have
correctly established the electrical
connection. This can be accomplished by
checking the trailer lighting. In this event,
Blind Spot Assist is deactivated. The indicator
lamp lights up yellow in the exterior mirrors
and the message: Blind Spot Assist
Currently Unavailable See
Operator's Manual appears in the
multifunction display.
i The indicator lamps in the exterior mirrors
can be switched off.
To do this, you must deactivate Blind Spot
Assist when:
R the key is in position 2 in the ignition
lock.
R the engine is not running.
R the electrical connection to the trailer
has been established.
Off-road driving systems
4MATIC (permanent four-wheel drive)
4MATIC ensures that all four wheels are
permanently driven. Together with ESP ®
and
4ETS , it improves the traction of your vehicle
whenever a drive wheel spins due to
insufficient grip.
GWarning!
If a drive wheel is spinning due to insufficient
traction:
R While driving off, apply as little throttle as
possible.
R While driving, ease up on the accelerator
pedal.
R Adapt your speed and driving style to the
prevailing road conditions.
Failure to observe these guidelines could
cause the vehicle to skid.
The 4MATIC cannot prevent accidents
resulting from excessive speed.
! Never tow the vehicle with one axle
raised. This may damage the transfer case.
Damage of this sort is not covered by the
Mercedes-Benz Limited Warranty. All
wheels must remain either on the ground
or be fully raised. Observe the instructions
for towing the vehicle with all wheels in full
contact with the ground.
i In wintry driving conditions, the maximum
effect of 4MATIC can only be achieved if
you use winter tires ( M+S tires), with snow
chains if necessary.
! When testing the parking brake, operate
the vehicle only briefly (for a maximum of
ten seconds) on a brake test dynamometer.
When doing this, turn the key to position
0 or 1 in the ignition. Failure to do this can
cause damage to the drive train or the
brake system.
! Function or performance tests may only
be performed on a 2-axle dynamometer. If
you wish to operate the vehicle on such a
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dynamometer, please consult an
authorized Mercedes-Benz Center
beforehand. You could otherwise damage
the drive train or the brake system.
Information on "Off-road driving"; see
( Y page 173).
DSR (Downhill Speed Regulation)
Important safety guidelines
DSR is an aid to assist you when driving
downhill. It keeps the speed of travel at the
speed selected on the on-board computer.
The steeper the downhill gradient, the greater
the DSR braking effect on the vehicle. When
driving on flat stretches of road or on an uphill
gradient, the DSR braking effect is minimal or
non-existent.
The speed is set to 4 mph (6 km/h) at the
factory; you can adjust this in the on-board
computer ( Y page 226).
GWarning!
Downhill Speed Regulation (DSR) is a
convenience system designed to assist the
driver during vehicle operation. The system
setting must be appropriate to the
topographical and weather conditions
encountered, which can change quickly. The
driver is responsible for the vehicle speed and
for safe brake operation at all times.
Depending on the programmed speed, actual
vehicle speed and gradient, switching on DSR
while driving can cause the vehicle to slow
down rapidly, and you may hear a sound,
caused by the activation of the vehicle's brake
system through DSR. Sudden and unexpected
deceleration can result in loss of vehicle
control, causing an accident and/or serious
personal injury to you and others. Do not
switch on DSR in a situation where rapid
deceleration could result in a loss of vehicle
control.
DSR controls the set speed when it is active
and the automatic transmission is in the D,
R or N position. You can drive at a higher or
a lower speed than that set on the on-board
computer at any time by accelerating or
braking.GWarning!
If you depress the accelerator pedal with DSR
activated, the vehicle can drive faster than the
programmed set speed. You should therefore
drive downhill with particular caution as it
could lead to an accident and/or serious
injury to you or others. Keep in mind that as
soon as you remove your foot from the
accelerator pedal with DSR switched on, DSR
will start regulating the vehicle's speed
including use of brakes if required. Depending
on the programmed set speed, actual vehicle
speed and gradient, DSR can cause the
vehicle to slow down rapidly. Sudden and
unexpected deceleration can result in loss of
vehicle control, causing an accident and/or
serious personal injury to you and others.
Information on "Off-road driving"; see
( Y page 173).
Activating/deactivating DSR
Activating
You can only activate DSR when driving at
speeds below 20 mph (30 km/h).
Vehicles without the Off-Road Pro engineering
package
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Vehicles with the Off-Road Pro engineering
package
XPress button :.
Indicator lamp ; lights up.
The DSR symbol and a message such as the
following appear in the multifunction display:
If the vehicle's speed is too high, the DSR
symbol and the Max. Speed 20 mph
(Canada: 30 km/h) message are shown in the
multifunction display.
Deactivating
XPress button :.
Indicator lamp ; goes out.
The DSR symbol appears in the
multifunction display with the Off
message.
DSR switches off automatically when you
drive at speeds over 21 mph (Canada:
35 km/h). The DSR symbol appears in the
multifunction display with the Off message.
You also hear a warning tone.
Changing the set speed while
the vehicle is in motion
When DSR is switched on, you can change the
set speed to a value between 3 mph and
10 mph (Canada: between 4 km/h and
18 km/h) while the vehicle is in motion.XTo increase or reduce the set speed in
1 mph (Canada: 1 km/h) increments:
briefly press the cruise control lever to the
pressure point, up : for a higher set speed
or down ; for a lower set speed.
The set value appears in the multifunction
display.XTo increase or reduce the set speed in
5 mph (Canada: 10 km/h) increments:
briefly press the cruise control lever past
the pressure point, up : for a higher set
speed or down ; for a lower set speed.
The set value appears in the multifunction
display.
Off-road drive program
i The off-road drive program is only
available on vehicles without the Off-Road
Pro Engineering package.
The off-road drive program assists you when
driving off-road. The engine's performance
characteristics and the gearshifting
characteristics of the automatic transmission
are adapted for this purpose. ABS, ESP ®
and
4ETS programs especially adapted to off-road
driving are also activated.
Do not use the off-road drive program on
roads that are snowy or icy or if your vehicle
has snow chains mounted.
For information on driving off-road, see
( Y page 173).
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XTo activate: press off-road button :.
Indicator lamp ; lights up. Off-road
indicator = appears in the multifunction
display.XTo deactivate: press off-road button :.
Indicator lamp ; and off-road indicator
= go out.
LOW RANGE
General notes
The LOW RANGE off-road gear assists you in
driving off-road and when fording. When LOW
RANGE is engaged, the engine’s performance
characteristics and the gearshifting
characteristics of the automatic transmission
are adapted for this purpose. ABS, ESP ®
and
4ETS programs especially adapted to off-road
driving are also activated.
For information on "Off-road driving", see
( Y page 173) . You will find information about
driving safety systems in conjunction with
LOW RANGE in the "Safety" section
( Y page 65).
Shift rangesHIGH RANGERoad position for all
normal driving situationsLOW RANGEOff-road position for
driving off-road and
fording
The gear ratio between the
engine and wheels is only
approximately one third of
that in the HIGH RANGE
road position. The drive
torque is correspondingly
higher as a result.
Do not use LOW RANGE:
R on slippery road
surfaces, e.g. in the case
of slush
R on snow or ice-covered
roads
R if you have mounted
snow chains to your
vehicleGWarning!
Always wait until the procedure of shifting
from HIGH RANGE to LOW RANGE – and from
LOW RANGE to HIGH RANGE – has been
entirely completed. During this procedure do
not turn off the engine or shift the automatic
transmission into another gear.
If you do not wait until the shifting procedure
has been entirely completed then it might not
be correctly performed. The transfer case
might be in neutral, thus interrupting the
transfer of power between the engine and the
drive axle.
The vehicle is then freely movable, even if a
gear has been selected, and could
unintentionally be set into motion –
particularly on up – or downhill grades. This
could lead to an accident and cause injury to
yourself and others.
Please observe related messages appearing
in the multifunction display.
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Differential lock
General notes
i Differential locks are available only in
vehicles with the Off-Road Pro engineering
package.
Your vehicle is equipped with the following:
R A differential lock for the transfer box: this
controls the balance between the front and
rear axles.
R A differential lock for the rear axle: this
controls the balance between the wheels
and the rear axle.
Differential locks improve the vehicle's
traction. 4ETS ( Y page 67)controls the
balance between the wheels on the front axle.
Information on "Off-road driving"; see
( Y page 173).
Information about the differential and
differential locks
When the vehicle is driving around a curve,
the wheels on the outside of the curve have
to cover a greater distance and therefore
have to turn faster than the wheels on the
inside. The differential, a transmission in the
drive train, balances these different rotational
speeds out, making cornering possible.
The disadvantage of a differential: the wheels
with the least grip are driven the hardest.
Example: one wheel on a driven axle is on a
snow-covered surface and therefore has no
traction. This wheel has the most driving
force, since the differential distributes most
of the force to the wheel with the least
resistance. The wheel on the opposite side of
this axle, which is on a solid surface and could
therefore enable traction, does not have any
driving force. 4ETS eliminates this
disadvantage and ensures good steerability
by braking the spinning wheel automatically
and thereby directing more force to the wheel
that is on a solid surface and can provide
traction.
ESP ®
and 4ETS are traction systems that are
ideally suited to road driving and driving on
easily negotiable off-road terrain. The LOW
RANGE off-road gear also improves off-road
capability.
Difficult off-road conditions require additional
measures, such as locking one or more
differentials. Your vehicle has two differential
locks: one (central) differential lock for the
transfer case and one differential lock for the
rear axle. Both differential locks can be
activated using the selector wheel on the
center console. When the (central)
differential for the transfer case is locked, the
speed of the front wheels is the same as the
speed of the rear wheels. When the
differential for the rear axle is locked, both of
the rear wheels turn at the same speed,
independent of their individual torques. Note
that activating the differential locks
significantly reduces the steerability of the
vehicle.
For your safety, the safety of others and to
prevent damage to the vehicle, the
differential locks must not be activated on
paved roads. Note that the differential
function is necessary when driving on paved
roads and that the differentials must never be
locked on paved roads. Otherwise, the
vehicle can no longer be steered. The
differential locks must therefore only be
activated when driving off-road, and then only
if activating the other driving systems (4ETS,
ESP ®
and LOW RANGE off-road gear) is no
longer sufficient.
Engaging the differential locks
! Drive off slowly when the differential
locks are engaged.
Function or performance tests may only be
performed on a 2-axle dynamometer. If you
wish to operate the vehicle on such a
dynamometer, please consult an
authorized Mercedes-Benz Center
beforehand. You could otherwise damage
the drive train or the brake system.
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Automatic mode
Use automatic mode ; for all driving
situations, including driving off-road or when
fording.
In automatic mode, the differential locks are
engaged and disengaged according to driving
requirements. This guarantees sufficient
traction for most driving situations with
unrestricted vehicle steerability.
XStart the engine.
The differential locks are in automatic
mode. The indicator lamp in selector
wheel : lights up above symbol for
automatic mode ;.
Engaging manually
GWarning!
Never drive on a paved surface with the center
and rear axle differential locks manually
engaged. Ability to steer the vehicle is greatly
reduced when the differential locks are
manually engaged, increasing the risk of an
accident.
For safety reasons, the locks are
automatically released at a vehicle speed
above 31 mph (50 km/h). Nevertheless, you
should only manually lock the differential if
absolutely necessary because engaged locks
will restrict the vehicle drivetrain while
cornering and cause the vehicle to chatter.
This could cause you to lose control of the
vehicle and cause an accident.
! The differential locks must not be
activated when the vehicle is being towed
or while the wheels are spinning.
Only engage the differential locks manually if
traction in automatic mode is insufficient.
At speeds of up to 19 mph (30 km/h), you
can engage the differential locks manually.XStart the engine.XTurn selector wheel : to desired position
= or ?.
The indicator lamp in selector wheel :
lights up at the corresponding symbol.
The engaged differential appears in the
multifunction display:
AThe differential lock for the transfer case
is locked.
If you have not previously selected the off-
road menu ( Y page 220) in the on-board
computer, the message disappears after
about five seconds.
The differential locks are not controlled
automatically. The steerability of the vehicle
is restricted considerably. Drive carefully and
accelerate gently for optimum traction.
! If the differential locks are activated
manually, the wheels scuff on the road
when cornering since the rotation
difference between the wheels is no longer
balanced out.
You can switch back to automatic mode at
any time. For safety reasons, the differential
locks disengage automatically at speeds
above 31 mph (50 km/h). If you stop the
vehicle and switch off the ignition for longer
than ten seconds, the differential locks
switch back to automatic mode.
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ROn long and steep gradients that are
difficult to drive down in shift range 1,
switch to the off-road drive program or
engage the LOW GEAR off-road gear.
R When driving downhill, shift to a lower gear
to utilize the engine's braking effect.
Avoid continuous brake application as this
may overheat the vehicle brakes and, if
installed, the trailer brakes.
R If the coolant temperature increases
dramatically while the air-conditioning
system is switched on, switch off the air-
conditioning system.
Coolant heat can additionally be dissipated
by opening the windows and by setting the
blower fan and the interior temperature to
maximum.
R When overtaking, pay particular attention
to the extended length of your vehicle/
trailer combination.
Due to the length of your vehicle/trailer
combination, you will have to travel an
additional distance beyond the vehicle you
are overtaking before returning to the
previous lane.
Decoupling a trailer
GWarning!
While you are coupling or decoupling a trailer,
make sure nobody locks or unlocks the
vehicle and/or opens or closes doors or the
tailgate.
The vehicle’s level could change and you
could endanger yourself and/or others as a
result.
Make sure that you do not operate the ADS
button or the vehicle level control system
when coupling/decoupling the trailer.
XMake sure that the automatic transmission
is set to position P.XApply the vehicle's parking brake.XStart the engine.XClose all doors and the tailgate.XApply the trailer's parking brake.GWarning!
As soon as you disconnect the electrical
connection between the trailer and the
vehicle, the vehicle will lower. To help avoid
personal injury, make sure no one is near the
wheel housing or underneath the vehicle
before the electrical connection is
disconnected.
When you decouple the trailer, the vehicle is
temporarily raised because the springs are
relieved of load. Be especially careful during
this process, as you could otherwise injure
yourself and/or others. Make sure that any
persons remaining in the vehicle do not press
the switches for vehicle level control or the
ADS.
XDetach the trailer cable and decouple the
trailer.XDetach the trailer cable and decouple the
trailer.XSwitch off the engine.
Permissible trailer load and drawbar
noseweight
Weight specifications
The Gross Trailer Weight (GTW) is the
combined weight of the trailer together with
the cargo and equipment loaded on the
trailer. Permissible gross weight: 7500 lb
(3402 kg).
The permissible Trailer drawbar Weight
Rating (TWR) is the maximum weight
permitted on the trailer drawbar: 600 lb
(272 kg) limit for Mercedes-Benz-approved
trailer couplings.
Loading a trailer
R When loading a trailer, please note that
neither the permissible gross trailer weight
nor the permissible Gross Vehicle Weight
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Rating (GVWR) may be exceeded. The
permissible Gross Vehicle Weight Rating
(GVWR) is specified on the type plate
located on the B-pillar on the driver's side
of your vehicle.
You can find the maximum permissible
values on the type plates of your vehicle
and the trailer. Always observe the lowest
respective value when determining the
maximum weight with which you can load
the vehicle and the trailer.
R The drawbar noseweight acting on the ball
coupling has to be added to the rear axle
weight in order to prevent the permissible
Gross Axle Weight Rating (GAWR) from
being exceeded. The permissible Gross
Vehicle Weight Rating (GVWR) is specified
on the type plate located on the B-pillar on
the driver's side of your vehicle.
i Mercedes-Benz recommends loading the
trailer so that the drawbar noseweight
remains between 8% and 15% of the
permissible gross trailer weight.
i The weight of additional accessories,
passengers, and cargo reduces the
permissible trailer load and drawbar
noseweight for your vehicle.
Checking the vehicle and trailer weight
R To check that the weights of the towing
vehicle and the trailer comply with the
maximum permissible values, have the
vehicle/trailer combination (including the
driver, passengers, and cargo with a fully
laden trailer) weighed on a calibrated
weighbridge.
R Check the permissible axle weight of the
front and rear axle, the Gross Trailer Weight
(GTW), and the drawbar noseweight.
Check the permissible axle weight of the
front and rear axle, the Gross Trailer Weight
(GTW), and the drawbar noseweight.
Trailer power supply
The trailer power socket of your vehicle is
designed for connecting the 7-pin connector
supplied as part of the Mercedes-Benz-
approved trailer coupling.
i Depending on your trailer, you may need
an adapter to connect your trailer to the
vehicle.
Further information is available from any
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