2008 MERCEDES-BENZ R320 flat tire

355 Operation
At the gas station
Engine oil level
For more information on engine oil, see
“Engine oil” (
page 358).
Coolant
For normal replenishing, use water (pota-
ble water quality). For more information,
see “Coolant level” (
page 360) and
“Fuels, coolants, lubricants, etc.”
(
page 536).
Brake fluidWindshield/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 362).
Vehicle lighting
Check function and cleanliness. For infor-
mation on replacing light bulbs, see “Re-
placing bulbs” (
page 480).
For more information, see “Exterior lamp
switch” (
page 143).
Tire inflation pressure
For more information, see “Checking tire
inflation pressure” (
page 373).
!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. Contact 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 539).

363 Operation
Tires and wheels
Tires and wheels
Contact an authorized Mercedes-Benz
Light Truck Center for information on
tested and recommended rims and tires
for summer and winter operation. They can
also offer advice concerning tire service
and purchase.Important guidelines

Only use sets of tires and rims of the
same type and make.

Tires must be of the correct size for the
rim.

Break in new tires for approximately
60 miles (100 km) at moderate
speeds.

Regularly check the tires and rims for
damage. Dented or bent rims can
cause tire inflation pressure loss and
damage to the tire beads.

If vehicle is heavily loaded, check tire
inflation pressure and correct as
required.

Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths of less than
1/8in (3 mm).

When replacing individual tires, you
should mount new tires on the front
wheels first (on vehicles with
same-sized wheels all around).
Warning!G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. See an authorized
Mercedes-Benz Light Truck Center for
further information. If incorrectly sized rims
and tires are mounted:

The wheel brakes or suspension
components can be damaged.

The operating clearance of the wheels
and the tires may no longer be correct.
Warning!G
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can
result in the bolts loosening and possibly an
accident.
Retreaded tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on
retreads. The operating safety of the vehicle
cannot be assured when such tires are used.

364 Operation
Tires and wheels
Tire care and maintenance
Regularly check the tire inflation pressure
at least once a month. For more informa-
tion on checking tire inflation pressure,
see “Recommended tire inflation pres-
sure” (
page 371).Tire inspection
Every time you check the tire inflation
pressure, you should also inspect your
tires for the following:

excessive treadwear (page 365)

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.
Damaged tires can cause tire inflation pres-
sure 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.

366 Operation
Tires and wheels
Loading the vehicle
Two labels on your vehicle show how much
weight it may properly carry.
1) The Tire and Loading Information
placard can be found on the driver’s
door B-pillar. This placard tells you im-
portant information about the number
of people that can be in the vehicle and
the total weight that can be carried in
the vehicle. It also contains information
on the proper size and recommended
tire inflation pressures for the original
equipment tires on your vehicle.2) The certification label, also found on
the driver’s door B-pillar. It tells you
about the gross weight capacity of your
vehicle, called the Gross Vehicle
Weight Rating (GVWR). The GVWR
includes the weight of the vehicle, all
occupants, fuel and cargo. The certifi-
cation label also tells you about the
front and rear axle weight capacity,
called the Gross Axle Weight Rating
(GAWR). The GAWR is the total allow-
able weight that can be carried by a
single axle (front or rear). Never exceed
the GVWR or GAWR for either the front
axle or rear axle.
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.
iSpare wheels may be mounted against the
direction of rotation (spinning) even with a
unidirectional tire for temporary use only until
the regular drive wheel has been repaired or
replaced. Always observe and follow applicable
temporary use restrictions and speed limitations
indicated on the spare wheel.

371 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 366).
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 352) for any additional infor-mation pertaining to special driving situa-
tions. For more information, see
“Important notes on tire inflation
pressure” (
page 372).
1Tire and Loading Information placard
with recommended cold tire inflation
pressuresWarning!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 driv-
er’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. Tire data are specific to each vehicle and
may vary from data shown in the following
illustration. Refer to Tire and Loading
Information placard on vehicle for actual data
specific to your vehicle.

372 Operation
Tires and wheels
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.Make 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 352).
Tire inflation pressure changes by approxi-
mately 1.5 psi (0.1 bar) per 18°F (10°C) of
air temperature change. Keep this in mind
when checking tire inflation pressure
where the temperature is different from
the outside temperature.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.

373 Operation
Tires and wheels
Checking tire inflation pressure
Regularly check the tire inflation pressure
at least once a month.
Check and adjust the tire inflation
pressure when the tires are cold. The tires
can be considered cold if the vehicle has
been parked for at least 3 hours or driven
less than 1 mile (1.6 km).
If you check the tire inflation pressure
when the tires are warm (the vehicle has
been driven for several miles or sitting less
than 3 hours), the reading will be
approximately 4 psi (0.3 bar) higher than
the cold reading. This is normal. Do not let
air out to match the specified cold tire
inflation pressure. Otherwise, the tire will
be underinflated.Checking tire inflation pressure
manually
Follow the steps below to achieve correct
tire inflation pressure:
Remove the cap from the valve on one
tire.
Firmly press a tire gauge onto the
valve.
Read tire inflation pressure on tire
gauge and check against the recom-
mended tire inflation pressure on the
Tire and Loading Information placard
on the driver’s door B-pillar
(
page 366) or, if available, the tire in-
flation pressure label on the inside of
the fuel filler flap. If necessary, add air
to achieve the recommended tire
inflation pressure.
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.


374 Operation
Tires and wheels
Install the valve cap.
Repeat this procedure for each tire.
Run Flat Indicator (Canada only)
While the vehicle is being driven, the Run
Flat Indicator monitors the set tire inflation
pressures by evaluating each wheel’s rota-
tional speed. This allows the system to de-
tect a significant loss of pressure in a tire.
If a wheel’s rotational speed changes due
to falling tire inflation pressure, you will
see a corresponding warning message in
the multifunction display.The Run Flat Indicator may function in a re-
stricted manner or with a delay

if snow chains are mounted to the
vehicle

in presence of ice and snow

if you are driving on a loose surface
(e.g. sand or gravel)

if you are driving in a very sporty
manner (involving rapid acceleration or
high speeds in curves)
iIf you have overfilled the tire, release tire in-
flation pressure by pushing the metal stem of the
valve with e.g. a tip of a pen. Then recheck the
tire inflation pressure with the tire gauge.Warning!G
When the multifunction display shows the
message
Tire Pressure Check Tires,
one or more of your tires is significantly un-
derinflated. You should stop and check your
tires as soon as possible, and inflate them to
the proper tire inflation pressure as in-
dicated on the vehicle’s Tire and Loading
Information placard or, if available, on the
tire inflation pressure label. Driving on a sig-
nificantly underinflated tire causes the tire
to overheat and can lead to tire failure. Un-
derinflation also reduces fuel efficiency and
tire tread life, and may affect the vehicle’s
handling and stopping ability. Each tire, in-
cluding the spare, should be checked
monthly when cold and set to the recom-
mended tire inflation pressure as specified
on the Tire and Loading Information placard
(
page 366) or on the tire inflation pres-
sure label located on the inside of the fuel
filler flap (
page 352).