Page 360 of 595

359 Operation
Driving instructions
Checklist before off-road driving
Engine oil level
Check the engine oil level with the oil
dipstick (
page 381).
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 389)).
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 497)
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.
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 396) 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 476) 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 381).
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.
Page 383 of 595

382 Operation
Engine compartment
Adding engine oil
Example GL 450 (GL 320 CDI similar)
1Filler cap
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 560) and
(
page 562).
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. To check the
coolant level, the vehicle must be parked
on level ground.
!Only use approved engine oils and oil filters
required for vehicles with Maintenance System.
For a listing of approved engine oils and oil
filters, refer to the Factory Approved Service
Products pamphlet (USA only) in your vehicle
literature portfolio, or contact an authorized
Mercedes-Benz Light Truck Center.
Using engine oils and oil filters of specification
other than those expressly required for the
Maintenance System, or changing of oil and oil
filter at change intervals longer than those called
for by the Maintenance System will result in
engine or emission control system damage not
covered by the Mercedes-Benz Limited
Warranty.
!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.
Page 563 of 595

562 Technical data
Fuels, coolants, lubricants
Engine oils
Engine oils are specifically tested for their
suitability in our engines and durability for
our service intervals. Therefore, only use
approved engine oils and oil filters
required for vehicles with Maintenance
System. For a listing of approved engine
oils and oil filters, refer to the Factory
Approved Service Products pamphlet
(USA only), or contact an authorized
Mercedes-Benz Light Truck Center.Engine oil additives
Air conditioning refrigerant
R-134a (HFC) refrigerant and special PAG
lubricating oil are used in the air
conditioning system.
Brake fluid
Only brake fluid approved by
Mercedes-Benz is recommended. Your
authorized Mercedes-Benz Light Truck
Center will provide you with additional
information.
!Using engine oils and oil filters of
specification other than those expressly
required for the Maintenance System, or chang-
ing of oil and oil filter at change intervals longer
than those called for by the Maintenance System
will result in engine or emission control system
damage not covered by the Mercedes-Benz
Limited Warranty.
Please follow Maintenance System recommen-
dations for scheduled oil changes. Failure to do
so will result in engine or emission control
system damage not covered by the
Mercedes-Benz Limited Warranty.
!Do not blend oil additives with engine oil.
They may damage the engine.
Damage or malfunctions resulting from blending
oil additives are not covered by the
Mercedes-Benz Limited Warranty.
!Never use R-12 (CFC) or mineral-based
lubricating oil. Otherwise damage to the system
will occur.
Warning!G
During vehicle operation, the boiling point of
the brake fluid is continuously reduced
through the absorption of moisture from the
atmosphere. Under extremely strenuous
operating conditions, this moisture content
can lead to the formation of bubbles in the
system, thus reducing the system’s
efficiency.
Therefore, the brake fluid must be replaced
regularly. Refer to your vehicle’s
Maintenance Booklet for replacement inter-
val.