MERCEDES-BENZ R500 2006 W251 Owner's Manual

350 OperationEngine compartmentR3501Filler capR5001Filler cap

Unscrew filler cap1 from filler neck.

Add engine oil as required. Never over-
fill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.

Screw filler cap1 back on filler neck.
For more information on engine oil, see
“Technical data” section (
page 521) and
(
page 523).
Transmission fluid level
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Light
Truck Center check the automatic trans-
mission.
!Excess oil must be siphoned or drained
off. It will cause damage to the engine
and catalytic converter not covered by
the Mercedes-Benz Limited Warranty.

351 Operation
Engine compartment
Coolant level
The engine coolant is a mixture of water
and anticorrosion / antifreeze. To check
the coolant level, the vehicle must be
parked on level ground and the engine
must be cool.
1Cap
2Coolant expansion tank
3Indicator wall
4Coolant level

Using a rag, turn cap 1 slowly approx-
imately one half turn counterclockwise
to release any excess pressure.

Continue turning cap 1 counterclock-
wise and remove it.
Coolant level 4 is correct if the level:

for cold coolant: reaches the top of
indicator wall 3 visible through the
filling opening


for warm coolant: is approximately
0.6 in (1.5 cm) higher

Add coolant as required.

Replace and tighten cap 1.
For more information on coolant, see the
“Technical data” section (
page 525).
Warning!
G
In order to avoid any possibly serious burns:

Use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system,
or if the coolant temperature gauge indi-
cates that the coolant is overheated.


Do not remove pressure cap on coolant
reservoir if coolant temperature is
above 158°F (70°C). Allow engine to
cool down before removing cap. The
coolant reservoir contains hot fluid and
is under pressure.


Using a rag, slowly open the cap approx-
imately
1/2 turn to relieve excess pres-
sure. If opened immediately, scalding
hot fluid and steam will be blown out un-
der pressure.


Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene gly-
col which may burn if it comes into con-
tact with hot engine parts.

352 OperationEngine compartmentWindshield / rear window washer
system and headlamp cleaning system*
The windshield washer reservoir is located
in the engine compartment.
1Cap
2Windshield washer reservoir
Fluid for the windshield washer system and
the headlamp cleaning system* is supplied
from the windshield washer reservoir. It
has a capacity of 8.0 US qt (7.6 l).During all seasons, add MB Windshield
Washer Concentrate “S” to water. Premix
the windshield washer fluid in a suitable
container.

Use the tab to pull cap1 upwards.

Refill the reservoir with MB Windshield
Washer Concentrate “S” and water (or
commercially available premixed wind-
shield washer solvent/antifreeze, de-
pending on ambient temperatures).
Always use washer solvent/antifreeze
where temperatures may fall below
freezing point. Failure to do so could
result in damage to the washer
system/reservoir.For more information, see “Windshield and
headlamp washer fluid mixing ratio”
(
page 528).
Warning!
G
Washer solvent/antifreeze is highly flamma-
ble. Do not spill washer solvent/antifreeze
on hot engine parts, because it may ignite
and burn. You could be seriously burned.
!Only use washer fluid which is suitable
for plastic lenses. Improper washer
fluid can damage the plastic lenses of
the headlamps.

353 Operation
Tires and wheels
Tires and wheels
See 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.
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.
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 under
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 fur-
ther 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.

354 OperationTires and wheelsTire 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 363).Tire inspection
Every time you check your tire inflation
pressure, you should also inspect your
tires for the following:


excessive treadwear (
page 355)


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.

355 Operation
Tires and wheels
Tread depth
Do not allow your tires to wear down too
far. Adhesion properties on wet roads are
sharply reduced at tread depths under 1/8in (3 mm).
Treadwear indicators (TWI) are required by
law. These indicators are located in six
places on the tread circumference and
become visible at a tread depth of approx-
imately
1/16
in (1.6 mm), at which point
the tire is considered worn and should be
replaced.
Recommended minimum tire tread depth:


Summer tires
1/8in (3 mm)


Winter tires
1/6in (4 mm)
1TWI (T
read W
ear I
ndicator)
The treadwear indicator appears as a solid
band across the tread.Storing tires
Cleaning tires
Warning!
G
Although the applicable federal motor safety
laws consider a tire to be worn when the
treadwear indicators (TWI) become visible at
approximately
1/16in (1.6 mm), we recom-
mend that you do not allow your tires
to wear down to that level. As tread depth
approaches
1/8in (3 mm), the adhesion
properties on a wet road are sharply re-
duced.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
!Keep unmounted tires in a cool, dry
place with as little exposure to light as
possible. Protect tires from contact
with oil, grease and gasoline.!Never use a round nozzle to power
wash tires. The intense jet of water can
result in damage to the tire.
Always replace a damaged tire.

356 OperationTires and wheelsDirection of rotation
Unidirectional tires offer added advan-
tages, such as better hydroplaning perfor-
mance. To benefit, however, you must
make sure the tires rotate in the direction
specified.
An arrow on the sidewall indicates the
intended direction of rotation (spinning) of
the tire.
Loading the vehicle
Two labels on your vehicle show how much
weight it may properly carry.

The Tire and Loading Information
placard (Example A) or the Vehicle Tire
Information placard (Example B) can be
found on the driver’s door B-pillar. This
placard tells you important 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.


The Certification label, also found on
the driver’s door B-pillar tells you about
the gross weight capacity of your vehi-
cle, called the Gross Vehicle Weight
Rating (GVWR). The GVWR includes the
weight of the vehicle, all occupants,
fuel and cargo. The Certification label
also tells you about the front and rear
axle weight capacity, called the Gross
Axle Weight Rating (GAWR). The GAWR
is the total allowable 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.
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 tempo-
rary use restrictions and speed limita-
tions indicated on the spare wheel.

357 Operation
Tires and wheels
1Driver’s door B-pillar
Following is a discussion on how to work
with the information contained on the two
placards with regards to loading your vehi-
cle.Tire and Loading Information
Your vehicle is equipped with either the
Tire and Loading Information placard
(Example A) or the Vehicle Tire Information
placard (Example B).Placard (Example A)
1Load limit information on the Tire and
Loading Information placard
Warning!
G
Do not overload the tires by exceeding the
specified load limit as indicated on the plac-
ard on the driver’s door B-pillar. Overloading
the tires can overheat them, possibly caus-
ing a blowout. Overloading the tires can also
result in handling or steering problems, or
brake failure.
iData shown on placard examples are
for illustration purposes only. Load lim-
it data are specific to each vehicle and
may vary from data shown in the illus-
trations below. Refer to placard on ve-
hicle for actual data specific to your
vehicle.

358 OperationTires and wheelsThe placard showing the load limit informa-
tion is located on the driver’s door B-pillar.
If your vehicle is equipped with the Tire and
Loading Information placard (Example A),
locate the statement “The combined
weight of occupants and cargo should
never exceed XXX kilograms or XXX lbs.”
on this placard. The combined weight of all
occupants, cargo/luggage and trailer
tongue load (if applicable) should never
exceed the weight referenced in that
statement.
Placard (Example B)
1Load limit information on the Vehicle
Tire Information placardThe placard showing the load limit informa-
tion is located on the driver’s door B-pillar.
If your vehicle is equipped with the Vehicle
Tire Information placard (Example B),
locate the heading “Vehicle Capacity
Weight” on this placard. The combined
weight of all occupants, cargo/luggage
and trailer tongue (if applicable) should
never exceed the weight listed next to
vehicle capacity weight.
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. Depending on
production date, your vehicle may be
equipped with placard Example A or plac-
ard Example B.
Your vehicle may not be equipped with
placard A nor other placard posting the
seating capacity. If this is the case, legal
requirements at time of production of your
vehicle did not require manufacturers to
post the seating capacity. Never let more people ride in the vehicle
than there are designated seating posi-
tions and seat belts available. Be sure
everyone riding in the vehicle is correctly
restrained with a separate seat belt.
iData shown on placard examples are
for illustration purposes only. Seating
data are specific to each vehicle and
may vary from data shown in the illus-
tration below. Refer to placard on vehi-
cle for actual data specific to your
vehicle.

359 Operation
Tires and wheels
Placard (Example A)1Seating capacityPlacard (Example B)1Seating capacitySteps 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 (Vehicles equipped with placard
Example A)

Locate the statement “The combined
weight of occupants and cargo should
never exceed XXX kg or XXX lbs.” on
your vehicle’s placard.
Step 1 (Vehicles equipped with placard
Example B)

Locate the heading “Vehicle Capacity
Weight” on your vehicle’s 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.
Step 4

The resulting figure equals the avail-
able amount of cargo and luggage load
capacity. For example, if the “XXX”
amount equals 1 400 lbs. and there will
be five 150 lbs. passengers in your
vehicle, the amount of available cargo
and luggage load capacity is 650 lbs.
(1 400 - 750 (5 x 150) = 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.