2007 MERCEDES-BENZ GL450 cooling

473 Practical hints
What to do if …
Display symbolDisplay messagesPossible cause/consequencePossible solution
Ï Coolant level
Stop car, switch engine offThe coolant is too hot.
Among other possible causes
(the cooling fan could be
malfunctioning), the poly-V-belt
could be broken.Stop the vehicle in safe location or as
soon as it safe to do so.
Apply the parking brake (page 68).
Turn off the engine.
Check the poly-V-belt.
If it is broken:
Do not continue to drive. Otherwise, the
engine will overheat due to an inoperative
water pump which may result in damage
to the engine. Contact an authorized
Mercedes-Benz Light Truck Center.
If it is intact:
Do not continue to drive the vehicle with
this message displayed. Doing so could
result in serious engine damage that is
not covered by the Mercedes-Benz Limit-
ed Warranty.
(Continued on next page)

475 Practical hints
What to do if …
Display symbolDisplay messagesPossible cause/consequencePossible solution
B Top up Coolant
See Oper. ManualThe coolant level is too low.Add coolant (page 382).
If you have to add coolant frequently,
have the cooling system checked by an
authorized Mercedes-Benz Light Truck
Center.
Warning!G
Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. You could be seriously burned.
!Do not ignore the low engine coolant level
warning. Extended driving with the message and
symbol displayed may cause serious engine
damage not covered by the Mercedes-Benz
Limited Warranty.
Do not drive without sufficient amount of coolant
in the cooling system. The engine will overheat
causing major engine damage.

491 Practical hints
What to do if …
Display symbolDisplay messagesPossible cause/consequencePossible solution
Visit workshopThe air suspension is malfunctioning.Do not drive faster than 50 mph
(80 km/h) depending on the set vehi-
cle level.
Have the vehicle checked at an autho-
rized Mercedes-Benz Light Truck
Center.
Compressor
cooling downYou have selected a higher vehicle level.
Due to frequent level changes within a
short period, the compressor must first
cool down.Let the compressor cool until the
message disappears.
The selected level will be set once the
compressor has cooled.
!When the message Compressor cooling
down
appears in the multifunction display,
driving is still possible. Keep in mind that the ride
height of the vehicle is not yet reached, so you
can damage the underbody of the vehicle. The
selected level will be set once the compressor
has cooled.

561 Technical data
Fuels, coolants, lubricants
ModelCapacityFuels, coolants, lubricants, etc.
Power steeringAll modelsapprox. 1.3 US qt (1.2 l)MB Power Steering Fluid or approved
Dexron III ATF
Front wheel hubsAll modelsapprox. 1.5 oz (43 g) eachHigh temperature roller bearing grease
Brake systemAll models-MB Brake Fluid (DOT 4+)
Cooling systemGL 320 CDIapprox. 10.0 US qt (9.5 l)MB Anticorrosion/Antifreeze
GL 450approx. 10.6 US qt (10.0 l)MB Anticorrosion/Antifreeze
Fuel Tank
including a reserve ofAll models26.4 US gal (100.0 l)
approx. 3.4 US gal (13.0 l)Gasoline engine:
Premium unleaded gasoline:
Minimum Posted Octane 91
(Avg. of 96 RON/86 MON)
Diesel engine:
ULTRA-LOW SULFUR DIESEL FUEL
(15 ppm SULFUR MAXIMUM)
Air conditioning systemAll models-R-134a refrigerant and special PAG lubricant oil
(never R-12)
Windshield washer system
and headlamp cleaning
system*All models8.1 US qt (7.7 l)MB Windshield Washer Concentrate1
1Use MB Windshield Washer Concentrate “MB SummerFit” and water for temperatures above freezing or MB Windshield Washer Concentrate “MB SummerFit” and
commercially available premixed windshield washer solvent/antifreeze for temperatures below freezing. Follow suggested mixing ratios (page 567).

565 Technical data
Fuels, coolants, lubricants
Coolants
The engine coolant is a mixture of water
and anticorrosion/antifreeze, which
provides:

Corrosion protection

Freeze protection

Boiling protection (by increasing the
boiling point)
The cooling system was filled at the factory
with a coolant providing freeze protection
to approximately -35°F (-37°C) and corro-
sion protection.If the antifreeze mixture is effective to
-35°F (-37°C), the boiling point of the cool-
ant in the pressurized cooling system is
reached at approximately 266°F (130°C).
The coolant solution must be used year
round to provide the necessary corrosion
protection and increase boil-over protec-
tion. Refer to Maintenance Booklet for
replacement interval.
Coolant system design and coolant used
determine the replacement interval. The
replacement interval published in the
Maintenance booklet is only applicable if
MB 325.0 Anticorrosion/Antifreeze solu-
tion or other Mercedes-Benz approved
products of equal specification are used to
renew the coolant concentration or bring it
back up to the proper level.
For information on other Mercedes-Benz
approved products of equal specification,
refer to the Factory Approved Service
Products pamphlet (USA only) or contact
an authorized Mercedes-Benz Light Truck
Center.To provide important corrosion protection,
the solution must be at least 50% anticor-
rosion/antifreeze (equivalent to freeze
protection to approximately -35°F
[-37°C]). If you use a solution that is more
than 55% anticorrosion/antifreeze (freeze
protection to approximately -49°F
[-45°C]), the engine temperature will
increase due to the lower heat transfer
capability of the solution. Therefore, do not
use more than this amount of anticorro-
sion/antifreeze.
If the coolant level is low, water and
MB 325.0 Anticorrosion/Antifreeze
should be used to bring it up to the proper
level (have cooling system checked for
signs of leakage). Please make sure the
mixture is in accordance with label instruc-
tions.
The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water. If you
are not sure about the water quality, con-
sult an authorized Mercedes-Benz Light
Truck Center.
!Add premixed coolant solution only. Adding
water and MB 325.0 Anticorrosion/Antifreeze
separately from each other, could cause engine
damage not covered by the
Mercedes-Benz Limited Warranty.

569 Index
A
ABS 103
Indicator lamp 436
Messages in the
multifunction display 453
Off-road - ABS 104
Accelerator position, automatic
transmission 198
Accessory weight 415
Accident 67
Active head restraint 92, 135, 504
Adaptive Damping System (ADS)* 280
Air bags 76
Children 77, 93
Front passenger front air bag off
indicator lamp 31, 32, 85
Front, Driver 79
Front, Passenger 79
Occupant Classification System*
(OCS) 81
Safety guidelines 78
Side impact (front and rear*) 80
Window curtain 80Air conditioning refrigerant 562
Air conditioning system see
Climate control or
Automatic climate control (3-zone)*
Air conditioning, Cooling 226, 241
Air distribution, Front 221, 236
Air distribution, Rear 229, 245
Air pressure see Tire inflation pressure
Air recirculation mode 224, 239
Air suspension package 280
Adaptive Damping System
(ADS)* 280
Messages in the
multifunction display 490
Vehicle level control 281
Air vents 229
Air vents*, Rear 246
Air vents, Front 222, 236
Air volume 222, 237
Alarm system see Anti-theft systems
Alignment bolt (vehicle tool kit) 496, 526
Anticorrosion/antifreeze 561, 566Antiglare, Interior rear view mirror 210
Antiglare, Rear view mirrors* 211
Antilock Brake System see ABS
Anti-theft systems 112
Anti-theft alarm system 111, 112
Immobilizer 111
Aquaplaning see Hydroplaning
Armrest storage compartments
Front 318
Ashtrays* 322
Aspect ratio 415
ATF 382
Attaching a trailer 368
Audio menu 166
CD operation 167
Radio operation 166
Satellite radio* operation
(USA only) 166
Auto-dimming*, Rear view mirrors 211
Automatic central locking,
Control system 183

570 Index
Automatic climate control (3-zone)* 230
Air conditioning refrigerant 561
Air conditioning, Cooling 241
Air distribution, Front 236
Air distribution, Rear 245
Air recirculation mode 239
Air vents*, second-row seats 246
Air vents*, third-row seats 247
Air vents, Front 236
Air volume 237
Control panel, Front 232
Control panel, Rear 243
Deactivating system 234
Defogging 237
Defrosting 237
Maximum cooling, MAXCOOL 239
Rear passenger compartment 243
Rear window defroster 215
Residual engine heat (REST) 242
Using driver-side settings for
all temperature zones 242Automatic headlamp mode 146
Automatic lighting control,
Interior lighting 152
Automatic locking when driving 130
Automatic transmission 58
Accelerator position 198
Emergency operation
(limp-home mode) 202
Gear ranges 200
Gear selector lever 58, 192
Gear selector lever position 195
Gear shifting malfunctions 202
Hill start assist system 199
Kickdown 198
Shifting procedure 195
Starting the engine 57
Steering wheel gearshift control 201
Towing a trailer 200
Transmission fluid level 382
Transmission positions 196
Automatic Transmission Fluid see ATFB
BabySmartTM
Air bag deactivation system 87, 450
Self-test 87
Backrest
Seat 46
Seat, Lumbar support 139
Seat, Multicontour* 140
Backup lamps
Messages in the
multifunction display 481
Replacing bulbs 515
Bar 416
BAS 105
Lamps in instrument cluster 436
Messages in the
multifunction display 453
Basic cross bars* 297
Batteries, SmartKey
Check lamp 114, 117
Checking battery condition 122
Messages in the
multifunction display 469
Replacing 506

572 Index
Children in the vehicle 93
Air bags 77, 93
Blocking rear door window
operation 100
Indicator lamp, Front passenger front
air bag 85, 87, 450
Infant and child restraint systems 88,
94
LATCH-type child seat anchors 97
Occupant Classification System*
(OCS) 81
Cigarette lighter* 324
Climate control 216
Air conditioning refrigerant 561
Air conditioning, Cooling 226, 227
Air distribution, Front 221
Air distribution, rear 229
Air recirculation mode 224
Air vents*, second-row seats 222
Air vents, Front 222
Air volume 222
Control panel*, Rear 228
Control panel, Front 218
Deactivating system 220
Defogging 224
Defrosting 223Rear window defroster 215
Residual engine heat (REST) 227
Clock 27, 176
Setting time 176
Cloth upholstery, Cleaning and
care of 434
Cockpit 24
Cockpit Management and Data System
see COMAND System
Cold tire inflation pressure 416
Collapsible wheel chock 498
COMAND System see separate operating
instructions
Combination switch 63, 65, 149
Compass 345
Adjustment 181
Calibration 182
Calling up the compass 345
Control and operation of radio
transmitters 372
Control system 157
Multifunction display 157
Multifunction steering wheel 158
Resetting to factory default 171Control system menus 157
Audio 166
DISTRONIC* 169
NAV* 168
Off-road 168
Settings 170
Standard display 164
TEL* 189
Trip computer 187
Vehicle configuration 185
Vehicle status message memory 169
Control system submenus 161, 163, 173
Comfort* 184
Instrument cluster 174, 175
Lighting 178
Time/Date 176
Vehicle 181
Coolant 382, 565
Anticorrosion/antifreeze mixing ratio
and quantity 566
Capacities 560
Checking coolant level 377, 382
Messages in the
multifunction display 473, 475
Temperature 374
Temperature display 164