2008 MERCEDES-BENZ ML320 pressure

316 Operation
Driving instructions
Treadwear indicators (TWI) are required by
law. These indicators are located in six
places on the tread circumference and
become visible at a tread depth of
approximately
1/16in (1.6 mm), at which
point the tire is considered worn and
should be replaced.
The treadwear indicator appears as a solid
band across the tread.Specified tire inflation pressures must be
maintained. This applies particularly if the
tires are subjected to high loads (e.g. high
speeds, heavy loads, high ambient temper-
atures).
For more information, see “Tires and
wheels” (
page 348).
Hydroplaning
Depending on the depth of the water layer
on the road, hydroplaning may occur, even
at low speeds and with new tires. Reduce
vehicle speed, avoid track grooves in the
road and apply brakes cautiously in the
rain.
Tire traction
The safe speed on a wet, snow covered or
icy road is always lower than on a dry road.
You should pay particular attention to the
condition of the road whenever the outside
temperatures are close to the freezing
point.
Inspect the tires and the vehicle underbody
for possible damage. If the vehicle or tires
appear unsafe, have the vehicle towed to
the nearest Mercedes-Benz Light Truck
Center or tire dealer for repairs.
Warning!G
Although the applicable federal motor
vehicle safety laws consider a tire to be
worn when the treadwear indicators (TWI)
become visible at approximately
1/16in
(1.6 mm), we recommend that you do not
allow your tires to wear down to that level.
As tread depth approaches 1/8in (3 mm),
the adhesion properties on a wet road are
sharply reduced.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
Warning!G
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
may 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.
Warning!G
If ice has formed on the road, tire traction
will be substantially reduced. Under such
weather conditions, drive, steer and brake
with extreme caution.


321 Operation
Driving instructions
Off-road driving rules

Engage the off-road driving program
(
page 253) before driving under
off-road conditions.

Vehicles with air suspension program*:
Make sure you select a vehicle level
(
page 255) appropriate to the topo-
graphical conditions. Always make
sure the vehicle has enough ground
clearance.

Fasten items being carried as securely
as possible (
page 266).

Always navigate gradients with the en-
gine on and with the transmission en-
gaged in a gear. Switch on the DSR
(
page 250) to help maintain a preset
speed.
!Observe the following during off-road
driving:

Keep doors, tailgate, windows, and
tilt/sliding sunroof closed whenever driving
off-road.

Adjust vehicle speed to condition of terrain.
The more uneven, rutty and steeper the ter-
rain, the lower the speed should be. Drive
through water slowly at an even speed,
avoiding a bow wave.

Be especially careful when driving in un-
known territory. It may be necessary to get
out of the vehicle and scout the path you in-
tend to take.

Watch out for obstacles, such as rocks,
holes, tree stumps and ruts.

Before driving through water, determine its
depth.

Do not stop vehicle while immersed in water,
and do not shut off the engine.

In sandy soil, drive at a steady speed as al-
lowed by conditions. This helps overcome
the vehicle rolling resistance and reduces
the likelihood of the vehicle sinking into the
ground.

Do not initiate jumps with the vehicle. It
interrupts the forward momentum of the
vehicle.

Always drive onto slopes with the engine
running and the vehicle in gear.

Do not shift automatic transmission to
positionN.
Warning!G
Do not reduce the tire inflation pressure
before driving through sand. However, if you
do so, remember to correct the tire inflation
pressure (
page 359) before continuing
your trip. Driving with reduced tire inflation
pressure increases the risk of losing control
of the vehicle and rolling over.

322 Operation
Driving instructions
Checklist before off-road driving
Engine oil level

Check the engine oil level with the oil
dipstick (
page 343).
Only with a proper oil level can the
vehicle obtain a trouble-free oil supply,
even on steep gradients.Tires

Check 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 (
page 352)).

Check tires for possible damage and
remove foreign objects.

Replace missing valve caps.
Rims

Dented or bent rims can cause tire in-
flation pressure loss and damage the
tire beads. For this reason, check and,
if necessary, change rims before driv-
ing off-road.
Vehicle tool kit

Check if the vehicle jack (page 450)
is functional.

In all cases take the vehicle tool kit, a
strong tow rope, a shovel and a small
plank (to put under the vehicle jack on
sandy soil) with you.Driving in steep terrain
Slope angle
1 Overhang angle, front
2Overhang angle, rear
!If the engine oil level warning lamp
(
page 434) 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 (
page 343).
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.
Vehicles with
steel suspen-
sion111
1Vehicles with AMG Sport-Package*
2
31°22°29°

325 Operation
Driving instructions

Before driving through water, deter-
mine its depth.

Vehicles with air suspension program*:
Select the highest vehicle level
possible (
page 255).

Switch to off-road driving program
(
page 253) before driving through
water.

Shift automatic transmission to
position1 or2 (
page 192).

Avoid high engine speeds.

Enter and leave the water only at a
shallow spot, driving at walking speed.

Drive through the water slowly and at a
constant speed.

Do not stop vehicle while immersed in
water, and do not shut off the engine.

There is a very high level of driving re-
sistance in water. The surface is slip-
pery and may not be firm, making
pulling away in water difficult and dan-
gerous.

Make sure that only small bow waves
are formed when driving the vehicle
through water.

Clean mud off the tire tread after driv-
ing through water.

To dry the brakes, apply pressure to the
brake pedal several times while driving
after leaving the water.Crossing obstacles
!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.
!Never accelerate before driving into the
water. The bow wave could force water into the
engine and auxiliary equipment, thus damaging
them.
!Do not open any of the vehicle’s doors while
driving through water. Water could otherwise en-
ter the vehicle interior and damage the vehicle’s
electronics, as well as the interior equipment.
!Obstacles can damage the vehicle
underbody or suspension components. If possi-
ble use the assistance of a second person out-
side 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, in-
spect 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.

326 Operation
Driving instructions
When driving over tree stumps, big rocks
and other obstacles, observe the following
rules:

Make sure the off-road driving program
(
page 253) is switched on.

Avoid high engine speeds.

Shift automatic transmission to
position1 (
page 192).

Check the vehicle clearance before
crossing obstacles.

Cross obstacles (e.g. tree stumps or
big rocks) very slowly by aiming one of
the front wheels at the center of the ob-
stacle, and repeat same with the rear
wheel.Driving on sand
When driving on sand, observe the follow-
ing rules:

Vehicles with air suspension program*:
Set the raised level (
page 255).

Avoid high engine speeds.

Shift automatic transmission into a
gear range that is appropriate for the
terrain.

In sandy soil, drive at a steady speed as
conditions permit. This helps overcome
the vehicle rolling resistance and re-
duce the likelihood of the vehicle sink-
ing into the ground.

Drive in tracks of other vehicles if they
are not too deep and you have suffi-
cient clearance.
Ruts
A number of off-road tracks or other by-
ways have deep ruts which can cause the
underbody to come in contact with the
ground.

Make sure the off-road driving program
(
page 253) is switched on.

Vehicles with air suspension program*:
Set the raised level (
page 255).
!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.
Warning!G
Do not reduce the tire inflation pressure
before driving through sand. However, if you
do so, remember to correct the tire inflation
pressure (
page 359) before continuing
your trip. Driving with reduced tire inflation
pressure increases the risk of losing control
of the vehicle and rolling over.

338 Operation
At the gas station
Briefly push on fuel filler flap1 at the
position indicated by the arrow.
Fuel filler flap1 opens slightly.
Open fuel filler flap1 completely.
Turn fuel filler cap2 counterclock-
wise and hold on to it until possible
pressure is released.
Take off fuel filler cap2.
Set fuel filler cap2 on fuel filler
flap1 as shown.
To prevent fuel vapors from escaping
into open air, fully insert filler nozzle
unit.
Only fill your tank until the filler nozzle
unit cuts out – do not top off or over-
fill.
Replace fuel filler cap2 by turning it
clockwise until it audibly engages.
Close fuel filler flap1.
You should hear the latch close shut.
!The fuel filler cap is tethered to the fuel filler
neck. Do not drop the cap. It could damage the
vehicle paint finish.
Warning!G
Overfilling of the fuel tank may create pres-
sure in the system which could cause a gas
discharge. This could cause the gas to spray
back out when removing the fuel pump noz-
zle, which could cause personal injury.
iMake sure to close the fuel filler flap before
locking your vehicle as the flap locking pin
prevents closing after you have locked the
vehicle.
iLeaving the engine running and the fuel cap
open can cause the yellow fuel tank reserve
warning lamp to flash and the ?malfunction
indicator lamp (USA only) or the± malfunc-
tion indicator lamp (Canada only) comes on.
For more information, see “Practical hints”
(
page 403).
iGasoline engine:
Only use premium unleaded gasoline with a min-
imum Posted Octane Rating of 91 (average of
96 RON/86 MON). Information on gasoline
quality can normally be found on the fuel pump.
Please contact gas station personnel in case
labels on the pump cannot be found.
For more information on gasoline, see “Premium
unleaded gasoline (gasoline engine)”
(
page 526), see “Fuel requirements”
(
page 526), and the Factory Approved Service
Products pamphlet (USA only) or contact an
authorized Mercedes-Benz Light Truck Center.
iDiesel engine:
Only use commercially available vehicular
ULTRA-LOW SULFUR HIGHWAY DIESEL FUEL
(15 ppm SULFUR MAXIMUM). Information on
diesel quality can normally be found on the fuel
pump. Please contact gas station personnel in
case labels on the pump cannot be found.
For more information on diesel fuels, refer to the
Factory Approved Service Products pamphlet
(USA only) or contact an authorized
Mercedes-Benz Light Truck Center.


340 Operation
At the gas station
Brake fluid
Coolant
For normal replenishing, use water (pota-
ble water quality).
For more information, see “Coolant level”
(
page 345) and see “Fuels, coolants, lu-
bricants” (
page 522).Windshield/rear window washer
system and headlamp cleaning
system*
For more information on refilling the wash-
er reservoir, see “Windshield/rear window
washer system and headlamp cleaning
system*” (
page 346).
Vehicle lighting
Check function and cleanliness. For infor-
mation on replacing light bulbs, see “Re-
placing bulbs” (
page 463).
For more information, see “Exterior lamp
switch” (
page 135).
Tire inflation pressure
For more information, see “Checking tire
inflation pressure” (
page 359).
!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. Notify an
authorized Mercedes-Benz Light Truck Center
immediately. Do not add brake fluid as this will
not solve the problem. For more information, see
“Brake fluid” (
page 525).

345 Operation
Engine compartment
Unscrew filler cap1 from filler neck.
Add engine oil as required. Never over-
fill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.
Screw filler cap1 back on filler neck.
For more information on engine oil, see
“Technical data” section (
page 522) and
(
page 525).
Transmission fluid level
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Light
Truck Center check the automatic trans-
mission.
Coolant level
The engine coolant is a mixture of water
and anticorrosion/antifreeze.
When checking the coolant level

the vehicle must be parked on level
ground

the coolant temperature must be below
158°F (70°C)
!Excess oil must be siphoned or drained off.
It could cause damage to the engine and/or
catalytic converter (gasoline engine) or the oxi-
dation catalyst (diesel engine) not covered by
the Mercedes-Benz Limited Warranty.
Warning!G
In order to avoid potentially serious burns:

Use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system,
or if the coolant temperature display
indicates that the coolant is overheated.

Do not remove pressure cap on coolant
reservoir if coolant temperature is
above 158°F (70°C). Allow engine to
cool down before removing cap. The
coolant reservoir contains hot fluid and
is under pressure.

Using a rag, slowly open the cap approx-
imately 1/2 turn to relieve excess pres-
sure. If opened immediately, scalding
hot fluid and steam will be blown out
under pressure.

Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene
glycol which may burn if it comes into
contact with hot engine parts.