Contents
Emission control .......................... 373
Coolant temperature .................... 374
At the gas station .............................. 375
Refueling ...................................... 375
Check regularly and
before a long trip.......................... 377
Engine compartment ......................... 379
Hood ............................................ 379
Engine oil ..................................... 381
Transmission fluid level ................ 382
Coolant level ................................ 382
Windshield/rear window
washer system and
headlamp cleaning system* ........ 384
Tires and wheels ................................ 385
Important guidelines .................... 385
Tire care and maintenance........... 386
Direction of rotation ..................... 388
Loading the vehicle ...................... 388
Recommended tire
inflation pressure ......................... 394
Checking tire inflation pressure ... 396
Tire labeling.................................. 406
Load identification ....................... 410
DOT, Tire Identification
Number (TIN) ............................... 410Maximum tire load ........................ 412
Maximum tire inflation pressure ... 412
Uniform Tire Quality Grading
Standards (U.S. vehicles) .............. 413
Tire ply material ............................ 415
Tire and loading terminology......... 415
Rotating tires ................................ 418
Winter driving ..................................... 420
Winter tires ................................... 420
Snow chains.................................. 421
Maintenance....................................... 422
Maintenance service indicator
message ....................................... 422
Calling up the maintenance
service indicator display ............... 424
Resetting the maintenance
service indicator ........................... 424
Vehicle care........................................ 425
Cleaning and care of the vehicle ... 425
Practical hints.................................. 435
What to do if … ................................... 436
Lamps in instrument cluster ......... 436
Lamp in center console ................ 448
Vehicle status messages in
the multifunction display .............. 451
Where will I find ...? ............................ 495
First aid kit.................................... 495
Vehicle tool kit.............................. 495
Spare wheel .................................. 499
Unlocking/locking in an emergency .. 500
Unlocking the vehicle ................... 500
Locking the vehicle ....................... 501
Fuel filler flap ................................ 501
Opening/closing in an emergency ..... 503
Power tilt/sliding sunroof* ........... 503
Resetting activated head restraints.... 504
Replacing SmartKey batteries ............ 506
Replacing bulbs .................................. 508
Bulbs............................................. 508
Replacing bulbs for front lamps .... 511
Replacing bulbs for rear lamps ..... 515
Adjusting headlamp aim ............... 518
67 Getting started
Driving
The coolant temperature is above
248°F (120°C)
The coolant is too hot and is no longer
cooling the engine.
Stop the vehicle in a safe location as
soon as possible and turn off the en-
gine. Allow engine and coolant to cool
off.
Check the coolant level and add cool-
ant if necessary (
page 382).In case of accident
If the vehicle is leaking fuel:
Do not start the engine under any
circumstances.
Notify local fire and/or police authori-
ties.
If the extent of the damage cannot be de-
termined:
Contact an authorized Mercedes-Benz
Light Truck Center or call Roadside
Assistance.
If no damage can be determined on the
major assemblies
fuel system
engine mount:
Start the engine in the usual manner.
161 Controls in detail
Control system
Menus, submenus and functions
Menu1Menu2Menu3Menu4Menu5
Standard displayAudioNAV*Off-roadDISTRONIC*
(page 164)(page 166)(page 168)(page 168)(page 169)
Commands/submenus
Trip- and main odometerSelecting radio stationRoute guidance
instructions, current
direction traveledCompassCalling up settings
Checking tire inflation pressureSelecting satellite radio
station* (USA only)Vehicle level
Checking coolant temperatureOperating CD playerDifferential locks*
Calling up digital speedometer
or outside temperature
Calling up maintenance service
indicator
iThe headings used in the menus table are
designed to facilitate navigation within the sys-
tem and are not necessarily identical to those
shown in the control system displays.The first function displayed in each menu will
automatically show you which part of the system
you are in.
370 Operation
Driving instructions
If the transmission repeatedly shifts
between gears on inclines, manually
shift to a lower gear (select 4, 3, 2 or 1)
(
page 200).
A lower gear and reduction of speed re-
duces the chance of engine overload-
ing and/or overheating.
On very steep inclines, not manageable
with automatic transmission in1,
switch on off-road driving program
(
page 280) or LOW RANGE mode*
(
page 203).
When going down a long hill, shift into
a lower gear and use the engine’s brak-
ing effect.
Avoid riding the brakes, thus overheat-
ing the vehicle and trailer brakes.
If the engine coolant rises to an ex-
tremely high temperature (coolant tem-
perature needle approaching the red
zone) when the air conditioning is on,
turn off the air conditioning system.
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 re-
turn to your lane.Uncoupling the trailer
!If the trailer should begin to sway, reduce
the vehicle’s speed immediately.
In no case attempt to straighten out the tow
vehicle and trailer by increasing the speed.
Warning!G
While you are coupling or decoupling a trail-
er, make sure that you do not
lock or unlock
open or close
a vehicle door 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* (
page 281) or the vehicle level
control system (
page 281) when cou-
pling/decoupling the trailer.
377 Operation
At the gas station
Low outside temperatures
(diesel engine)
To prevent malfunctions, diesel fuel with
improved cold flow characteristics is of-
fered in the winter months. Check with
your fuel retailer.Check regularly and before a long trip
Open the hood (page 379).
Example GL 450 (GL 320 CDI similar)
1Brake fluid
2Coolant level
3Windshield washer system and
headlamp cleaning system*
Engine oil level
For more information on engine oil, see
“Engine oil” (
page 381).
iDiesel engine:
If you have driven the vehicle until the tank is
empty, the fuel system needs to be bled
(
page 529).
!Diesel engine:
The engine is more susceptible to wear and
damage if you use
marine diesel fuel
heating oil
additives
The exhaust aftertreatment device will be
seriously damaged if you use
LOW SULFUR DIESEL FUEL
(500 ppm SULFUR MAXIMUM)
any other diesel fuel with a sulfur content of
above 15 ppm
The use of such non-approved fuels and/or
special additives is not covered by the
Mercedes-Benz Limited Warranty.
!Do not fill the tank with gasoline. Do not
blend diesel fuel with gasoline or kerosine. The
fuel system and engine will otherwise be dam-
aged, which is not covered by the
Mercedes-Benz Limited Warranty.
378 Operation
At the gas station
Brake fluid
Coolant
For normal replenishing, use water (pota-
ble water quality).
For more information, see “Coolant level”
(
page 382) and see “Fuels, coolants, lu-
bricants” (
page 560).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 384).
Vehicle lighting
Check function and cleanliness. For infor-
mation on replacing light bulbs, see “Re-
placing bulbs” (
page 508).
For more information, see “Exterior lamp
switch” (
page 145).
Tire inflation pressure
For more information, see “Checking tire
inflation pressure” (
page 396).
!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 562).
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.
383 Operation
Engine compartment
The coolant expansion tank is located on
the driver’s side of the engine compart-
ment.
1Cap
2Coolant expansion tank
3Indicator wall
4Coolant levelUsing a rag, turn cap1 slowly approx-
imately one half turn counterclockwise
to release any excess pressure.
Continue turning cap1 counterclock-
wise and remove it.
Coolant level4 is correct if the level:
for cold coolant: reaches the top of
indicator wall3 visible through the
filling opening
for warm coolant: is approximately
0.6 in (1.5 cm) higher
Add coolant as required.
Replace and tighten cap1.
For more information on coolant, see
“Coolants” (
page 565).
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 gauge indi-
cates 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 un-
der pressure.
Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene gly-
col which may burn if it comes into con-
tact with hot engine parts.