Page 408 of 595

407 Operation
Tires and wheels
General:
Depending on the design standards used,
the tire size molded into the sidewall may
have no letter or a letter preceding the tire
size designation.
No letter preceding the size designation
(as illustrated above): Passenger car tire
based on European design standards.
Letter “P” preceding the size designation:
Passenger car tire based on U.S. design
standards.
Letter “LT” preceding the size designation:
Light Truck tire based on U.S. design
standards.
Letter “T” preceding the size designation:
Temporary spare tires which are high
pressure compact spares designed for
temporary emergency use only.Tire width
The tire width1 (
page 406) indicates
the nominal tire width in mm.
Aspect ratio
The aspect ratio2 (
page 406) is the
dimensional relationship between tire
section height and section width and is
expressed in percentage. The aspect ratio
is arrived at by dividing section height by
section width.
Tire code
The tire code3 (
page 406) indicates
the tire construction type. The “R” stands
for radial tire type. Letter “D” means diag-
onal or bias ply construction; letter “B”
means belted-bias ply construction.
At the tire manufacturer’s option, any tire
with a speed capability above 149 mph
(240 km/h) can include a “ZR” in the size
designation (for example: 245/40 ZR 18).
For additional information, see “Tire speed
rating” (
page 408).Rim diameter
The rim diameter4 (
page 406) is the
diameter of the bead seat, not the
diameter of the rim edge. Rim diameter is
indicated in inches (in).
Tire load rating
The tire load rating5 (
page 406) is a
numerical code associated with the
maximum load a tire can support.
For example, a load rating of 91 corre-
sponds to a maximum load of 1 356 lbs
(615 kg) the tire is designed to support.
See also “Maximum tire load”
(
page 412) where the maximum load as-
sociated with the load index is indicated in
kilograms and lbs.
Page 416 of 595

415 Operation
Tires and wheels
Tire ply material
1Plies in sidewall
2Plies under tread
This marking tells you about the type of
cord and number of plies in the sidewall
and under the tread.Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, radio, and heater, to the extent that
these items are available as
factory-installed equipment (whether
installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire.
Air pressure is expressed in pounds per
square inch (psi), or kilopascal (kPa) or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.
Warning!G
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underin-
flation, or excessive loading, either sepa-
rately or in combination, can cause
excessive heat build-up and possible tire
failure.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
Page 466 of 595

465 Practical hints
What to do if …
Display messagePossible cause/conse-
quencePossible solution
(Vehicles with OCS* only)
Front passenger airbag
disabled
See Operator’s Manual
Front passenger front air bag is
deactivated while driving even
though an adult or someone
larger than a small individual is
occupying the front passenger
seat. Forces acting on the seat
may make the system sense a
decrease in weight.Stop the vehicle in a safe location as soon as possible and check the front
passenger seat for the following:
Apply the parking brake (page 68).
Switch off the ignition (page 42).
Have the front passenger vacate the seat and exit the vehicle.
Adjust the seat in a height position (page 46).
Make sure that no objects which apply forces to the seat are present
(e.g. objects such as books, briefcases etc. lodged underneath, behind
or around the seat). Such forces may cause the system to sense that
an occupant of a lesser weight than actually present is on the front
passenger seat.
Keep the seat unoccupied, close the front passenger door and switch
on the ignition (
page 42).
(Continued on next page)
Page 492 of 595
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.
Page 519 of 595
518 Practical hints
Replacing bulbs
License plate lamp
1License plate lamp cover
2Screws
Loosen screws2.
Remove license plate lamp cover1.
Replace the tubular bulb.
Reinstall license plate lamp cover1.
Retighten screws2.
Adjusting headlamp aim
VVertical centerline
HHeadlamp mounting height, measured
from the centerCorrect headlamp adjustment is extremely
important. To check and readjust a head-
lamp, follow the steps described:
Park the vehicle on a level surface
25 feet (7.6 m) from a vertical test
screen or wall.
Switch the headlamps on
(
page 145).
If the beam does not show a beam pattern
as indicated in the figure left, then follow
the steps below:
Open hood (page 379).
iHigh beam adjustments simultaneously aim
the low beam.
Vehicle should have a normal tailgate load.
Page 559 of 595
558 Technical data
Main Dimensions
ModelGL 320 CDI, GL 450
Overall vehicle length200.6 in (5096 mm)
Vehicle width (exterior rear view mirrors folded out)83.7 in (2127 mm)
Vehicle width (exterior rear view mirrors folded in)76.0 in (1930 mm)
Overall vehicle height, depending on set vehicle level72.4 in - 75.6 in (1840 mm - 1920 mm)
Overall vehicle height, depending on set vehicle level
(vehicles with enhanced off-road package*)72.4 in - 76.8 in (1840 mm - 1950 mm)
Wheelbase121.1 in (3075 mm)
Ground clearance, depending on set vehicle level7.8 in - 10.9 in (197 mm - 277 mm)
Ground clearance, depending on set vehicle level
(vehicles with enhanced off-road package*)7.8 in - 12.1 in (197 mm - 307 mm)
Turning circle39.7ft (12.1m)
Track, front65.0 in (1651 mm)
Track, rear65.1 in (1654 mm)
Page 579 of 595

578 Index
Headlamps
Automatic headlamp mode 146
Bi-Xenon* 481, 512
Cleaning lenses 429
Cleaning system* 210, 384
Halogen 511
High beam see High beam flasher
High beam see High beam headlamps
Light sensor, Messages in the
multifunction display 483
Low beam see Low beam headlamps
Manual headlamp mode 146
Messages in the
multifunction display 481, 482,
483, 484, 485, 486
Replacing bulbs 508, 509
Switch 62, 145
Heated seats see Seat heating*
Heated steering wheel* 328
Height adjustment
Vehicle level control
(Vehicles with Air suspension
package) 283
Vehicle level control
(Vehicles with enhanced Off-road
Package*) 285High beam flasher 63, 149
High beam headlamps
Indicator lamp 29
Messages in the
multifunction display 482
Replacing bulbs 509, 511, 512
Switching on 63, 149
High mounted brake lamp 509
Hill start assist system 199
Hinged quarter windows* see
Power windows
Hood 379
Messages in the
multifunction display 478
Opening 379
Hooks
Loading 306
Horn 25
HVAC see Climate control or
automatic climate control (3-zone)*
Hydroplaning 354I
Identification labels see Labels
Ignition 42, 44, 59
Immobilizer 111
Indicator lamps see Lamps, Indicator and
warning
Infant and child restraint systems see
Children in the vehicle
Inflation pressure see Tires,
Inflation pressures
Information button see Tele Aid
Infrared reflecting windshield* 345
Inside door handle 122
Instrument cluster 26, 28, 155
Illumination brightness 155
Lamps 436
Messages in display see Multifunction
display messages
Multifunction display 157
Outside temperature indicator 156
Selecting language 174
Instrument lighting see Instrument cluster,
Illumination brightness
Instrument panel see Instrument cluster
Page 587 of 595

586 Index
Seat belts 88
Children in the vehicle 93
Cleaning 433
Fastening 54
Height adjustment 56
Messages in the
multifunction display 443, 444
Proper use of 56, 90
Safety guidelines 78
Telltale 29, 88, 443
Warning lamp 444
Seat cushion depth see Seats
Seat heating* see Seats
Seat ventilation* see Seats
Seating capacity 390
Seats 45, 132
Adjusting 45
Cushion depth, Multicontour
seat* 140
Easy entry/exit feature for
third-row seats 132
Emergency exit for
third-row seats 134
Heating* 140
Lumbar support 139Memory function* 143
Multicontour seat* 140
Second-row, Folding 308
Third-row, Folding electrically 307,
310
Ventilation* 142
Securing cargo 304
Cargo tie-down rings 304
Hooks 306
Selector lever see Gear selector lever
Self-test
BabySmart
TM air bag deactivation
system 87
Lamps in the instrument cluster 436
OCS* 86
Tele Aid 333
Vehicle battery 530
Service and warranty information 10
Service intervals see Maintenance, Service
indicator
Service life
Tires 386
Service see Maintenance
Service system see Maintenance System
Service, Parts 548Settings
Adaptive Damping System
(ADS)* 280
Air suspension 280
Clock 176
Comfort functions* 184
Control system menus 160, 162
Control system submenus 161, 163,
173
Date 163, 173, 176
Daytime running lamp mode 178
Factory, SmartKey 116
Factory, SmartKey with
KEYLESS-GO* 120
Individual, Vehicle 170
Instrument cluster 174
Language, multifunction display 174,
175
Lighting 178
Memory function* 144
Resetting all, Control system 171
Selective, SmartKey 116
Selective, SmartKey with
KEYLESS-GO* 121
Time 176
Vehicle configuration 185