2008 MERCEDES-BENZ GL320 tire pressure

347 Operation
Driving instructions
Driving instructions
Drive sensibly – save fuel
Fuel consumption, to a great extent,
depends on driving habits and operating
conditions.
To save fuel you should:

Keep tires at the recommended infla-
tion pressures.

Remove unnecessary loads.

Remove carriers* when not in use.

Remove the crossbars* when not in
use.

Allow engine to warm up under low
load use.

Avoid frequent acceleration and decel-
eration.

Have all maintenance work performed
at the intervals specified in the
Maintenance Booklet and as required
by the Maintenance System. Contact
an authorized Mercedes-Benz Light
Truck Center.Fuel consumption is also increased by
driving in cold weather, in stop-and-go traf-
fic, on short trips and in hilly areas.
Drinking and driving
Pedals
Warning!G
Drinking and driving and/or taking drugs
and driving are a very dangerous combina-
tion. Even a small amount of alcohol or
drugs can affect your reflexes, perceptions
and judgment.
The possibility of a serious or even fatal
accident are greatly increased when you
drink or take drugs and drive.
Do not drink or take drugs and drive or allow
anyone to drive who has been drinking or
taking drugs.
Warning!G
Make sure that absolutely no objects are ob-
structing the pedal’s range of movement.
Keep the driver’s footwell clear of all obsta-
cles. If there are any floormats or carpets in
the footwell, make sure that the pedals still
have sufficient clearance.
During sudden driving or braking maneu-
vers, the objects could get caught between
the pedals. You could then no longer brake
or accelerate. This could lead to accidents
and injury.
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351 Operation
Driving instructions
Tires
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).

Turn the SmartKey or the SmartKey with
KEYLESS-GO* to starter switch
position0 and remove, or press
KEYLESS-GO* start/stop button (vehi-
cles with KEYLESS-GO*).

Take the SmartKey or the SmartKey with
KEYLESS-GO* with you and lock vehicle
when leaving.
Warning!G
If you feel a sudden significant vibration or
ride disturbance, or you suspect that possi-
ble damage to your vehicle has occurred,
you should turn on the hazard warning flash-
ers, carefully slow down, and drive with cau-
tion 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 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.
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357 Operation
Driving instructions
Checklist before off-road driving
Engine oil level

Check the engine oil level with the oil
dipstick (
page 380).
Only with a proper oil level can the
vehicle obtain a trouble-free oil supply,
even on steep gradients.
!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 395) before continuing
your trip. Driving with reduced tire inflation
pressure increases the risk of losing control
of the vehicle and rolling over.
!If the engine oil level warning lamp
(
page 473) 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 380).
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.
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358 Operation
Driving instructions
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 388)).

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 492)
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

Comply with the warnings
(
page 355) and rules for off-road
driving (
page 356).

Driving on embankments, slopes and
other steep inclines should only be
done straight up or downhill, i.e. in the
line of gravity. Maximum vehicle climb-
ing ability is a 100% grade which is
equivalent to a slope angle of
45 degrees. Keep in mind that the
climbing ability of the vehicle depends
on terrain conditions.
Vehicles with air sus-
pension program12
Raised level34°28°
Highway29°23°
Vehicles with
enhanced off-road
package*12
Off-road-level 336°30°
Off-road-level 234°28°
Off-road-level 131°25°
Highway29°23°
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361 Operation
Driving instructions

Select the highest vehicle level
possible (
page 279).

Switch to off-road driving program
(
page 277) or LOW RANGE mode*
(
page 201) before driving through
water.

Shift automatic transmission to
position1 or2 (
page 197).

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
!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.
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362 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 277) or if equipped the LOW
RANGE mode* (
page 201) is
switched on.

Avoid high engine speeds.

Shift automatic transmission to
position1 (
page 197).

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:

Set the raised level (page 279).

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 277), or if equipped, the LOW
RANGE mode* (
page 201) is
switched on.

Set the raised level (page 279).!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 395) 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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377 Operation
At the gas station
Brake fluid
Coolant
For normal replenishing, use water (pota-
ble water quality).
For more information, see “Coolant level”
(
page 381) and see “Fuels, coolants, lu-
bricants” (
page 562).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 383).
Vehicle lighting
Check function and cleanliness. For infor-
mation on replacing light bulbs, see “Re-
placing bulbs” (
page 504).
For more information, see “Exterior lamp
switch” (
page 143).
Tire inflation pressure
For more information, see “Checking tire
inflation pressure” (
page 395).
!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 564).
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384 Operation
Tires and wheels
Contact an authorized Mercedes-Benz
Light Truck Center for information on test-
ed and recommended rims and tires for
summer and winter operation. They can
also offer advice concerning tire service
and purchase.Important guidelines

Only use sets of tires and rims of the
same type and make.

Tires must be of the correct size for the
rim.

Break in new tires for approximately
60 miles (100 km) at moderate
speeds.

Regularly check the tires and rims for
damage. Dented or bent rims can
cause tire inflation pressure loss or
damage to the tire beads.

If vehicle is heavily loaded, check tire
inflation pressure and correct as
required.

Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths of less than
1/8in (3 mm).

When replacing individual tires, you
should mount new tires on the front
wheels first (on vehicles with
same-sized wheels all around).
Warning!G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. Contact an authorized
Mercedes-Benz Light Truck Center for fur-
ther information. If incorrectly sized rims
and tires are mounted:

The wheel brakes or suspension
components can be damaged.

The operating clearance of the wheels
and the tires may no longer be correct.
Warning!G
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can
result in the bolts loosening and possibly an
accident.
Retreaded tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on re-
treads. The operating safety of the vehicle
cannot be assured when such tires are used.
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