MERCEDES-BENZ ML320 2001 W163 Owner's Manual

188 Driving instructions
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Crossing obstacles:
Select gear range “1” on the automatic transmission,
see page 165.
Cross 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.
Important!
Damage on the vehicle definitely increases the chance
for a subsequent accident.Notes:
Check the vehicle clearance before crossing obstacles
that possibly could damage the undercarriage.
If possible use the assistance of a second person.
Special attention is needed when crossing obstacles on
a steep incline. The vehicle could slide sideways as a
result of its possible slanted position.
Ruts:
Select gear range “1” on the automatic transmission,
see page 165.
A number of off-road tracks or other byways have deep
ruts which can cause the undercarriage to come in
contact with the ground.
Drive next to the ruts rather than through them if at all
possible.
Notes:
Check the vehicle clearance.
Damage on the vehicle definitely increases the chance
for a subsequent accident.

189 Driving instructions
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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:
•Switch off the LOW RANGE mode, see page 209.
•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.
•Inspect frame, oil pan, brake hoses, etc., as well as
vehicle underbody for possible damage.
•Check tires for possible damage, clean all exterior
lamps, and conduct a brake test.•Check for brush or branches caught in the
undercarriage. They 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.
Wa r n i n g !
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 roadway.Inspect the tires and under the vehicle for possible
damage. If the vehicle or tires appear unsafe, have
it towed to the nearest Mercedes-Benz Light Truck
Center or tire dealer for repairs.

190 Driving instructions
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Trailer towingTrailer Hitches
Only install a trailer hitch receiver approved for your
vehicle. For information on availability and installation,
please see your authorized Mercedes-Benz Light Truck
Center.
The bumpers on your vehicle are not designed for use
with clamp-type hitches. Do not attach rental hitches or
other bumper-type hitches to them.
To reduce the possibility of damage, remove the hitch
ball adaptor from the receiver when not in use.
Wa r n i n g !
Failure to use proper equipment and driving
technique can result in a loss of vehicle control
when towing a trailer.Improper towing or failure to follow the
instructions contained in this guide can result in
serious injury. Follow the guidelines below
carefully to assure safe trailer operation.Ask your authorized Mercedes-Benz Light Truck
Center should you require an explanation of
information contained in this guide.

191 Driving instructions
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The vehicle is prewired to accept the seven-wire harness
included in the Mercedes-Benz approved trailer hitch
receiver kit. An additional four-pole conversion plug is
included in the Mercedes-Benz supplied trailer hitch
receiver kit. For further information, please see your
authorized Mercedes-Benz Light Truck Center.
In order to prevent possible damage to the vehicle’s
electrical system by incorrectly installing the trailer
wiring plug, we recommend having the harness
connected at an authorized Mercedes-Benz Light Truck
Center.Vehicle and trailer weights and ratings
Gross Vehicle Weight Rating (GVWR) is the maximum
permissible vehicle weight: 6005 lbs. (2724 kg)
Gross Vehicle Weight (GVW): comprises weight of
vehicle including fuel, tools, spare wheel, installed
accessories, passengers, cargo and trailer tongue. It
must never exceed the GVWR.
Gross Axle Weight Rating (GAWR) is the maximum
permissible axle weight:
Gross Trailer Weight (GTW) is the maximum
permissible trailer weight to be towed:
5000 lbs. (2260 kg)
Trailer Tongue Weight Rating (TWR) is the maximum
permissible weight of the trailer tongue:
[500 lbs. (225 kg) limit for MB approved hitch receiver] front
rear2755 lbs.
3527 lbs.(1250 kg)
(1600 kg)

192 Driving instructions
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Loading a trailer
When loading a trailer, you should observe that neither
the permissible GTW, nor the GVWR are exceeded.
Maximum permissible values are listed on the safety
compliance certification labels for the vehicle and for
the trailer to be towed. The lowest value listed must be
selected when determining how the vehicle and trailer
are loaded.
We recommend loading the trailer in such a manner
that it has a tongue weight (TW) between 10% and 15%
of the GTW.
The tongue weight at the hitch ball must be added to the
GVW to prevent exceeding your Mercedes-Benz tow
vehicle’s rear GAWR.Checking weights of vehicle and trailer
To assure that the tow vehicle and trailer are in
compliance with the maximum permissible weight
limits, and to know the actual weights, have the loaded
rig (tow vehicle including driver, passengers and cargo,
trailer fully loaded) weighed on a commercial scale.
Check the vehicle’s front and rear Gross Axle Weight
(GAW), the GTW and TW. The values as measured must
not be exceeded, according to the weight listed under
“Vehicle and trailer weight and ratings”.

193 Driving instructions
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Please observe maximum permitted trailer dimensions
(width and length).
Most states and all Canadian provinces require safety
chains between your tow vehicle and the trailer. The
chains should be crisscrossed under the trailer tongue.
They must be attached to the hitch receiver, and not to
the vehicle’s bumper or axle. Be sure to leave enough
slack in the chains to permit turning corners.
Most states and all Canadian provinces require a
separate brake system at various trailer weights.Caution!
Do not connect a trailer brake system (if trailer is so
equipped) directly to the vehicle’s hydraulic brake
system, as your vehicle is equipped with antilock
brakes. If you do, neither the vehicle’s brakes nor the
trailer’s brakes will function properly.
The provided vehicle electrical wiring harness for trailer
towing has a brake signal wire (color orange) for
hook-up to a brake controller.
Most states and all Canadian provinces require a
break-away switch on trailers with a separate brake
system. The switch activates the trailer brakes in the
possible event that the trailer might separate from the
tow vehicle.
You should consider using a trailer sway control system.
For further information see your authorized
Mercedes-Benz Light Truck Center.

194 Driving instructions
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Tow in g a t r ai le r
There are many different laws, including speed limit
restrictions, having to do with trailer towing. Make sure
t ha t your rig will be lega l, not only for w here you reside,
but also for where you will be driving. A good source for
this information can be the police or local authorities.
Before you start driving with the trailer, check the
trailer hitch, break-away switch, safety chains, electrical
connections, lighting and tires. Also adjust the mirrors
to permit unobstructed view beyond rear of trailer.
If the trailer has electric brakes, start your vehicle and
trailer moving slowly, and then apply only the trailer
brake controller by hand to be sure the brakes are
working properly.
When towing a trailer, check occasionally to be sure that
the load is secure, and that lighting and trailer brakes
(if so equipped) are functioning properly.
Always secure items in the trailer to prevent load shifts
while driving.
Take into consideration that when towing a trailer, the
handling characteristics are different and less stable
from those when operating the vehicle without a trailer.
It is important to avoid sudden maneuvers.The vehicle and trailer combination is heavier, and
therefore is limited in acceleration and climbing ability,
and requires longer stopping distances. It is more prone
to reacting to side wind gusts, and requires more
sensitive steering input.
In order to gain skill and an understanding of the
vehicle’s behavior, you should practice turning,
stopping and backing up in an area which is free from
traffic.
If possible, do not brake abruptly, but rather engage the
brake slightly at first to permit the trailer to activate its
brake. Then increase the braking force.
Caution!
If the trailer should begin to sway, reduce the vehicle’s
speed and use the brake controller by hand to straighten
out the vehicle and trailer. In no case should you
attempt to straighten out the tow vehicle and trailer by
increasing the speed or oversteering and stepping on
the brakes.
If the transmission hunts between gears on inclines,
manually shift to a lower gear (select “4”, “3”, “2”
or “1”). A lower gear and reduction of speed reduces the
chance of engine overloading and / or overheating.

195 Driving instructions
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cluster displayPractical hints Car care Index At very steep inclines, not manageable with selector
lever in position “1”, switch transfer case to LOW
RANGE, see page 209 for instructions on how to engage
LOW RANGE.
When going down a long hill, shift into a lower gear and
use the engine’s braking effect. Avoid riding the brakes,
thus overheating the vehicle and trailer brakes.
If the engine coolant rises to an extremely high
temperature (coolant temperature needle approaching
the red zone) when the air conditioner is on, turn off the
air conditioner. Engine coolant heat can be additionally
vented by opening the windows, switching the climate
control fan speed to high and setting the temperature
control to the maximum hot position.
Extreme care must be exercised since your vehicle with
a trailer will require additional passing distance ahead
than when driving without a trailer. Because your
vehicle and trailer is longer than your vehicle alone, you
will also need to go much farther ahead of the passed
vehicle before you can return to your lane.Parking
Wa r n i n g !
To reduce the risk of personal injury, or damage to
the vehicle powertrain, as a result of vehicle/trailer
movement, always:1. Keep right foot on brake pedal.2. Shift gear selector lever to position “N”.3. Have a second person place wheel chocks on
downhill side of left and right trailer wheels.4. Slowly release brake pedal and let vehicle and
trailer roll into chocks until stopped.5. Firmly depress parking brake pedal.6. Move gear selector lever to position “P”.7. On inclines turn front wheels towards the road
curb.

196 Driving systems
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Cruise control
The cruise control allows you to drive in a more relaxed
manner, for example over long distances, as it
automatically maintains the set speed by actively
regulating the throttle setting.
Any given speed above approximately 25 mph
(40 km / h) can be maintained with the cruise control by
operating the lever.1Accelerate and set:
Lift lever briefly to set speed.
Hold lever up to accelerate.
2Decelerate and set:
Depress lever briefly to set speed.
Hold lever down to decelerate.
Normally the vehicle is accelerated to the desired
speed with the accelerator.
Speed is set by briefly pushing the lever to
position 1 or 2. The accelerator can then be
released.
The speed can be increased (e.g. for passing) by
using the accelerator. After the accelerator is
released, the previously set speed will be resumed
automatically.
If a set speed is to be increased or decreased
slightly, e.g. to adapt to the traffic f low, hold lever in
position 1 or 2 until the desired speed is reached, or
briefly tip the lever in the appropriate direction for
increases or decreases in 0.6 mph (1 km / h)
increments. When the lever is released, the newly
set speed remains.
1
4
2
3

197 Driving systems
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cluster displayPractical hints Car care Index 3Canceling
To cancel the cruise control, briefly push lever to
position 3.
When you step on the brake pedal or the vehicle
speed drops below approximately 25 mph
(40 km / h), for example when driving upgrade, the
cruise control will be canceled.
If the cruise control cancels by itself and remains
inoperative until the engine is restarted, have the
system checked at your authorized Mercedes-Benz
Light Truck Center as soon as possible.
4Resume
If the lever is briefly pushed to position 4 when
driving at a speed exceeding approximately 25 mph
(40 km / h), the vehicle resumes the speed which
was set prior to the cancellation of the cruise
control. The last memorized speed is canceled when
the key in the steering lock is turned to position 1
or 0.Important!
Moving gear selector lever to position “N” switches the
cruise control off.
Wa r n i n g !
Only use the cruise control if the traffic and
weather conditions make it advisable to travel at a
steady speed.• The use of cruise control can be dangerous on
winding roads or in heavy traffic because
conditions do not allow safe driving at a steady
speed.
• The use of cruise control can be dangerous on
slippery roads. Rapid changes in tire adhesion
can result in wheel spin and loss of control.The “Resume” function should only be operated if
the driver is fully aware of the previously set speed
and wishes to resume this particular preset speed.