2008 MERCEDES-BENZ GL550 page 164

385 Operation
Tires and wheels
Tire care and maintenance
Regularly check your tire inflation pressure
at least once a month. For more informa-
tion on checking tire inflation pressure,
see “Recommended tire inflation pres-
sure” (
page 393).Tire inspection
Every time you check your tire inflation
pressure, you should also inspect your
tires for the following:

excessive treadwear (page 386)

cord or fabric showing through the
tire’s rubber

bumps, bulges, cuts, cracks or splits in
the tread or side of the tire
Replace the tire if you find any of the above
conditions.
Make sure you also inspect the spare tire
periodically for condition and inflation.
Spare tires will age and become worn over
time even if never used, and thus should be
inspected and replaced when necessary.Life of tire
The service life of a tire is dependent upon
varying factors including but not limited to:

Driving style

Tire inflation pressure

Distance driven
Warning!G
Regularly check the tires for damage. Dam-
aged tires can cause tire inflation pressure
loss. As a result, you could lose control of
your vehicle.
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
Warning!G
Tires and spare tire should be replaced after
6 years, regardless of the remaining tread.
164.boo Seite 385 Freitag, 30. März 2007 12:54 12

388 Operation
Tires and wheels
1Driver’s door B-pillar
Following is a discussion on how to work
with the information contained on the Tire
and Loading Information placard with
regards to loading your vehicle.Tire and Loading Information
Tire and Loading Information placard1Load limit information on the Tire and
Loading Information placard
The Tire and Loading Information placard
showing the load limit information is
located on the driver’s door B-pillar
(
page 388).
Locate the statement “The combined
weight of occupants and cargo should
never exceed XXX kilograms or
XXX lbs.” on the Tire and Loading Infor-
mation placard.
The combined weight of all occupants,
cargo/luggage and trailer tongue load
(if applicable) should never exceed the
weight referenced in that statement.
Warning!G
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard 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.
iData shown on Tire and Loading Information
placard example are for illustration purposes
only. Load limit data are specific to each vehicle
and may vary from data shown in the illustration
below. Refer to Tire and Loading Information
placard on vehicle for actual data specific to your
vehicle.
164.boo Seite 388 Freitag, 30. März 2007 12:54 12

389 Operation
Tires and wheels
Seating capacity
The seating capacity gives you important
information on the number of occupants
that can be in the vehicle. Observe front
and rear seating capacity. The Tire and
Loading Information placard showing the
seating capacity is located on the driver’s
door B-pillar (
page 388).
1Seating capacity information on the
Tire and Loading Information placard.
Steps for determining correct load limit
The following steps have been developed
as required of all manufacturers under
Title 49, Code of U.S. Federal Regulations,
Part 575 pursuant to the “National Traffic
and Motor Vehicle Safety Act of 1966”.Step 1
Locate the statement “The combined
weight of occupants and cargo should
never exceed XXX kg or XXX lbs.” on
your vehicle’s Tire and Loading
Information placard.
Step 2
Determine the combined weight of the
driver and passengers that will be
riding in your vehicle.
Step 3
Subtract the combined weight of the
driver and passengers from
XXX kilograms or XXX lbs.
iData shown on Tire and Loading Information
placard example are for illustration purposes
only. Seating data are specific to each vehicle
and may vary from data shown in the illustration
below. Refer to Tire and Loading Information
placard on vehicle for actual data specific to your
vehicle.

164.boo Seite 389 Freitag, 30. März 2007 12:54 12

390 Operation
Tires and wheels
Step 4
The resulting figure equals the avail-
able amount of cargo and luggage load
capacity. For example, if the “XXX”
amount equals 1400 lbs and there will
be five 150 lbs passengers in your
vehicle, the amount of available cargo
and luggage load capacity is 650 lbs
(1400-750 (5 x150) = 650 lbs).
Step 5
Determine the combined weight of
luggage and cargo being loaded on the
vehicle. That weight may not safely
exceed the available cargo and luggage
load capacity calculated in step 4.Step 6 (if applicable)
If your vehicle will be towing a trailer,
load from your trailer will be trans-
ferred to your vehicle. Consult this
manual to determine how this reduces
the available cargo and luggage load
capacity of your vehicle (
page 392).
The following table shows examples on
how to calculate total and cargo load
capacities with varying seating configura-
tions and number and size of occupants.
The following examples use a load limit
of 1500 lbs. This is for illustration
purposes only. Make sure you are using
the actual load limit for your vehicle stated
on the vehicle’s Tire and Loading
Information placard (
page 388).

164.boo Seite 390 Freitag, 30. März 2007 12:54 12

391 Operation
Tires and wheels
The higher the weight of all occupants, the
less cargo and luggage load capacity is
available.
For more information, see “Trailer tongue
load” (
page 392).
ExampleCombined
weight limit
of occu-
pants and
cargo from
placardNumber of
occupants
(driver and
passengers)Seating
configura-
tionOccupants weight Combined
weight of all
occupantsAvailable cargo/luggage and trailer
tongue weight (total load limit from
placard minus combined weight of
all occupants)
11500 lbs5front: 2
rear: 3Occupant 1: 150 lbs
Occupant 2: 180 lbs
Occupant 3: 160 lbs
Occupant 4: 140 lbs
Occupant 5: 120 lbs750 lbs1500 lbs - 750 lbs = 750 lbs
21500 lbs3front: 1
rear: 2Occupant 1: 200 lbs
Occupant 2: 190 lbs
Occupant 3: 150 lbs540 lbs1500 lbs - 540 lbs = 960 lbs
31500 lbs1front:1Occupant 1: 150 lbs150 lbs1500 lbs - 150 lbs = 1350 lbs
164.boo Seite 391 Freitag, 30. März 2007 12:54 12

392 Operation
Tires and wheels
Certification label
Even after careful determination of the
combined weight of all occupants, cargo
and the trailer tongue load (if applicable)
(
page 392) as to not exceed the permis-
sible load limit, you must make sure that
your vehicle never exceeds the Gross
Vehicle Weight Rating (GVWR) and the
Gross Axle Weight Rating (GAWR) for ei-
ther the front or rear axle. You can obtain
the GVWR and GAWR from the certification
label. The certification label can be found
on the driver’s door B-pillar, see “Technical
data” (
page 547).Gross Vehicle Weight Rating (GVWR): The
total weight of the vehicle, all occupants,
all cargo, and the trailer tongue load
(
page 392) must never exceed the
GVWR.
Gross Axle Weight Rating (GAWR): The to-
tal allowable weight that can be carried by
a single axle (front or rear).
To assure that your vehicle does not ex-
ceed the maximum permissible weight
limits (GVWR and GAWR for front and rear
axle), have the loaded vehicle (including
driver, passengers and all cargo and, if
applicable, trailer fully loaded) weighed on
a suitable commercial scale.Trailer tongue load
The tongue load of any trailer is an impor-
tant weight to measure because it affects
the load you can carry in your vehicle. If a
trailer is towed, the tongue load must be
added to the weight of all occupants riding
and any cargo you are carrying in the
vehicle. The tongue load typically is
between 8% and 15% of the trailer weight
and everything loaded in it.
For more information on trailer tongue
load, see “Loading a trailer” (
page 365).
164.boo Seite 392 Freitag, 30. März 2007 12:54 12

393 Operation
Tires and wheels
Recommended tire inflation pressure
Your vehicle is equipped with the Tire and
Loading Information placard located on the
driver’s door B-pillar (
page 388).
The tire inflation pressure should be
checked regularly and should only be ad-
justed on cold tires. The tires can be con-
sidered cold if the vehicle has been parked
for at least 3 hours or driven less than
1 mile (1.6 km).Follow recommended cold tire inflation
pressures listed on Tire and Loading
Information placard on the driver’s door
B-pillar.
Keeping the tires properly inflated
provides the best handling, tread life and
riding comfort.
In addition to the Tire and Loading
Information placard on the driver’s door
B-pillar, also consult the tire inflation
pressure label (if available) on the fuel filler
flap (page 374) for any additional infor-
mation pertaining to special driving situa-
tions. For more information, see
“Important notes on tire inflation pressure”
(
page 394).
Warning!G
Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly,
adversely affect handling and fuel economy,
and are more likely to fail from being over-
heated.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride
comfort, wear unevenly, increase stopping
distance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road
debris, potholes etc.
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard 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.
164.boo Seite 393 Freitag, 30. März 2007 12:54 12

394 Operation
Tires and wheels
1Tire and Loading Information placard
with recommended cold tire inflation
pressures
The Tire and Loading Information placard
lists the recommended cold tire inflation
pressures for maximum loaded vehicle
weight. The tire inflation pressures listed
apply to the tires installed as original
equipment.Important notes on tire inflation
pressure
Tire temperature and tire inflation pressure
are also increased while driving, depending
on the driving speed and the tire load.
If you will be driving your vehicle at high
speeds of 100 mph (160 km/h) or higher,
where it is legal and conditions allow,
consult the tire inflation pressure label on
the inside of the fuel filler flap (if available)
on how to adjust the cold tire inflation
pressure. If you do not adjust the tire infla-
tion pressure, excessive heat can build up
and result in sudden tire failure.If your vehicle is not equipped with the tire
inflation pressure label on the inside of the
fuel filler flap, contact an authorized
Mercedes-Benz Light Truck Center for
proper tire inflation pressure.
Be sure to readjust the tire inflation
pressure for normal driving speeds. You
should wait until the tires are cold before
adjusting the tire inflation pressure.
Some vehicles may have supplemental tire
inflation pressure information for vehicle
loads less than the maximum loaded vehi-
cle condition. If such information is provid-
ed, it can be found on the tire inflation
pressure label located on the inside of the
fuel filler flap (
page 374).
iData shown on Tire and Loading Information
placard example are for illustration purposes
only. Tire data are specific to each vehicle and
may vary from data shown in the illustration
below. Refer to Tire and Loading Information
placard on vehicle for actual data specific to your
vehicle.
Warning!G
If the tire inflation pressure drops
repeatedly:

Check the tires for punctures from
foreign objects.

Check to see whether air is leaking from
the valves or from around the rim.
iDriving comfort may be reduced when the
tire inflation pressure is adjusted to the value for
speeds above 100 mph (160 km/h) as specified
on the tire inflation pressure label located on the
inside of the fuel filler flap.
164.boo Seite 394 Freitag, 30. März 2007 12:54 12