2007 MERCEDES-BENZ GL450 Brake

403 Operation
Tires and wheels
Warning!G
It is the driver’s responsibility to calibrate
the TPMS on the recommended cold infla-
tion pressure. Underinflated tires affect the
ability to steer or brake the vehicle. You
might lose control over the vehicle.
iWith a spare wheel without wheel sensor
mounted, the system may still indicate the tire
inflation pressure of the removed wheel for some
minutes. If this happens, keep in mind that the
indicated value where the spare wheel is mount-
ed does not reflect the actual spare tire inflation
pressure.
Warning!G
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust tire inflation pressure according to
the Tire and Loading Information placard on
the driver’s door B-pillar or, if available, the
supplemental tire inflation pressure infor-
mation on the inside of the fuel filler flap.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of pressure (e.g.
tire blowout caused by a foreign object). In
this case bring the vehicle to a halt by care-
fully applying the brakes and avoiding
abrupt steering maneuvers.
Warning!G
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
Tire and Loading Information placard on the
driver’s door B-Pillar or, if available, the tire
inflation pressure label on the fuel filler flap.
If your vehicle has tires of a different size
than the size indicated on the vehicle plac-
ard or the tire inflation pressure label, you
should determine the proper tire inflation
pressure for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitor-
ing system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires are significantly underinflated. Accord-
ingly, when the low tire pressure telltale illu-
minates, you should stop and check your
tires as soon as possible. Driving on a signif-
icantly underinflated tire causes the tire to
overheat and can lead to tire failure.


404 Operation
Tires and wheels
Reactivating Advanced TPMS*
The TPMS must be reactivated when you
have adjusted the tire inflation pressure to
a new level (e.g. because of different load
or driving conditions). The TPMS is then
recalibrated to the current tire inflation
pressures.
Using the Tire and Loading Information
placard on the driver’s door B-pillar
(
page 389) or, if available, the sup-
plemental tire inflation pressure
information on the inside of the fuel
filler flap (
page 375), make sure the
tire inflation pressure of all four tires is
correct.
Press buttonè orÿ on the mul-
tifunction steering wheel repeatedly
until the standard display menu
appears in the multifunction display
(
page 157).
Press thej or kbutton repeat-
edly until you see the current inflation
pressures for each tire appear in the
display or the following message ap-
pears in the display
Underinflation also reduces fuel efficiency
and tire tread life, and may effect the vehi-
cle’s handling and stopping ability. Please
note that the TPMS is not a substitute for
proper tire maintenance, and it is the driv-
er’s responsibility to maintain correct tire
pressure, even if under-inflation has not
reached the level to trigger illumination of
the TPMS low tire pressure telltale.
iOperating radio transmission equipment
(e.g. wireless headsets, two-way radios) in or
near the vehicle could cause the TPMS to mal-
function.
Warning!G
It is the driver’s responsibility to calibrate
the TPMS on the recommended cold infla-
tion pressure. Underinflated tires affect the
ability to steer or brake the vehicle. You
might lose control over the vehicle.
iReactivate the TPMS after adjusting the tire
inflation pressure to the inflation pressure rec-
ommended for the vehicle operating condition.
Tire pressure should only be adjusted on cold
tires. Observe the recommended tire inflation
pressure on the Tire and Loading Information
placard on the driver’s door B-pillar
(
page 389). Some vehicles may have supple-
mental tire inflation pressure information for
driving at high speeds (
page 395) or for vehi-
cle loads less than the maximum loaded vehicle
condition (
page 395). If such information is
provided, it can be found on the inside of the fuel
filler flap.


408 Operation
Tires and wheels
For additional information on tire load
rating, see “Load identification”
(
page 410).
Tire speed rating
The tire speed rating6 (
page 406)
indicates the approved maximum speed
for the tire.Summer tires
Warning!G
The tire load rating must always be at least
half of the GAWR (
page 416) of your
vehicle. Otherwise, tire failure may be the
result which may cause an accident and/or
serious personal injury to you or others.
Always replace rims and tires with the same
designation, manufacturer and type as
shown on the original part.
Warning!G
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard located on
the driver’s door B-pillar. Overloading the
tires can overheat them, possibly causing a
blowout. Overloading the tires can also
result in handling or steering problems, or
brake failure.
iTire load rating5 (page 406) and Tire
speed rating6 (
page 406) are also referred
to as “service description”.
Warning!G
Even when permitted by law, never operate
a vehicle at speeds greater than the
maximum speed rating of the tires.
Exceeding the maximum speed for which
tires are rated can lead to sudden tire
failure, causing loss of vehicle control and
possibly resulting in an accident and/or
personal injury and possible death, for you
and for others.
iTire load rating5 (page 406) and Tire
speed rating6 (
page 406) are also referred
to as “service description”.
IndexSpeed rating
Qup to 100 mph (160 km/h)
Rup to 106 mph (170 km/h)
Sup to 112 mph (180 km/h)
Tup to 118 mph (190 km/h)
Hup to 130 mph (210 km/h)
Vup to 149 mph (240 km/h)
Wup to 168 mph (270 km/h)
Yup to 186 mph (300 km/h)
(Y)above 186 mph (300 km/h)
ZRabove 149 mph (240 km/h)

412 Operation
Tires and wheels
Maximum tire load
1Maximum tire load rating
The maximum tire load is the maximum
weight the tires are designed to support.For more information on tire load rating
(
page 407).
For information on calculating total and
cargo load capacities (
page 390).
Maximum tire inflation pressure
1Maximum permissible tire inflation
pressure
This is the maximum permissible tire
inflation pressure for the tire.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
Warning!G
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard located on
the driver’s door B-pillar. Overloading the
tires can overheat them, possibly causing a
blowout. Overloading the tires can also
result in handling or steering problems, or
brake failure.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.

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.

417 Operation
Tires and wheels
Maximum load rating
The maximum load in kilograms and
pounds that can be carried by the tire.
Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
total load limit and production options
weight.
Maximum tire inflation pressure
This number is the greatest amount of air
pressure that should ever be put in the tire
under normal driving conditions.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by
68 kilograms (150 lbs).
Occupant distribution
The distribution of occupants in a vehicle
at their designated seating positions.Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.
PSI (P
ounds per square inch)
A standard unit of measure for air pressure
-> bar, kilopascal (kPa).
Recommended tire inflation pressure
Recommended tire inflation pressure for
normal driving conditions is listed on the
Tire and Loading Information placard locat-
ed on driver’s door B-pillar. Provides best
handling, tread life and riding comfort. If so
equipped, supplemental information per-
taining to special driving situations can be
found on the tire inflation pressure label on
the inside of the fuel filler flap.Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
Sidewall
The portion of a tire between the tread and
the bead.
TIN (Tire Identification Number)
Unique identifier which facilitates efforts
by tire manufacturers to notify purchasers
in recall situations or other safety matters
concerning tires and gives purchases the
means to easily identify such tires. The TIN
is comprised of “Manufacturer’s identifica-
tion mark”, “Tire size”, “Tire type code”
and “Date of manufacture”.
Tire load rating
Numerical code associated with the
maximum load a tire can support.

419 Operation
Tires and wheels
In some cases, such as when your vehicle
is equipped with mixed-size tires (different
tire dimension front vs. rear), tire rotation
is not possible.
If applicable to your vehicle’s tire configu-
ration, tires can be rotated according to
the tire manufacturer’s recommended in-
tervals in the tire manufacturer’s warranty
pamphlet located in your vehicle literature
portfolio. If none is available, tires should
be rotated every 3 000 to 6 000 miles
(5 000 to 10 000 km), or sooner if neces-
sary, according to the degree of tire wear.
The same rotation (spinning) direction
must be maintained (
page 388).
Rotate tires before the characteristic tire
wear pattern becomes visible (shoulder
wear on front tires and tread center wear
on rear tires).
Thoroughly clean the mounting face of
wheels and brake disks, i.e. the inner side
of the wheels/tires, during each rotation.
Check for and ensure proper tire inflation
pressure.For information on wheel change, see the
“Practical hints” section (
page 495) and
(
page 523).
Warning!G
Have the tightening torque checked after
changing a wheel. Wheels could become
loose if not tightened with a torque of
110 lb-ft (150 Nm).
Only use genuine Mercedes-Benz wheel
bolts specified for your vehicle’s rims.

425 Operation
Vehicle care
Vehicle care
Cleaning and care of the vehicle
Regular and proper care will help to
maintain the value of your vehicle. The
best way to protect your vehicle from
harmful environmental influences is to
wash it and use protective treatments
regularly.While in operation, even while parked, your
vehicle is subjected to varying external in-
fluences which, if gone unchecked, can at-
tack the paintwork as well as the
underbody and cause lasting damage.
Such damage is caused not only by
extreme and varying climatic conditions,
but also by:

Air pollution

Road salt

Tar

Gravel and stone chipping
To avoid paint damage, you should
immediately remove:

Grease and oil

Fuel

Coolant

Brake fluid

Bird droppings

Insects

Tree resins, etc.Frequent washing reduces and/or
eliminates the aggressiveness and
potency of the above adverse influences.
More frequent washings are necessary to
deal with unfavorable conditions:

near the ocean

in industrial areas (smoke, exhaust
emissions)

during winter operation
You should check your vehicle from time to
time for stone chipping or other damage.
Any damage should be repaired as soon as
possible to prevent corrosion.
In doing so, do not neglect the underbody
of the vehicle. A prerequisite for a thor-
ough check is a washing of the underbody
followed by a thorough inspection. Dam-
aged areas need to be re-undercoated.Warning!G
Many cleaning products can be hazardous.
Some are poisonous, others are flammable.
Always follow the instructions on the partic-
ular container. Always open your vehicle’s
doors or windows when cleaning the inside.
Never use fluids or solvents that are not de-
signed for cleaning your vehicle.
Always lock away cleaning products and
keep them out of reach of children.