Page 369 of 570

368 Operation
Engine compartment
If there is excess engine oil with the engine
at operating temperature, the following
message will appear:
Engine oil level
Reduce oil level
Have excess oil siphoned or drained
off. Contact an authorized
Mercedes-Benz Light Truck Center.
For more information on messages in the
multifunction display concerning engine
oil, see the “Practical hints” section
(
page 459).Checking engine oil level with the oil
dipstick (except R 500)
When checking the oil level
the vehicle must be parked on level
ground
with the engine at operating tempera-
ture, the vehicle must have been
stationary for at least 5 minutes with
the engine turned off
with the engine not at operating tem-
perature yet, the vehicle also must
have been stationary for at least
5 minutes with the engine turned off1Oil dipstick
2Upper mark
3Lower mark
Open the hood (page 364).
Pull out oil dipstick1.
Wipe oil dipstick 1 clean.
Fully insert oil dipstick1 into the
dipstick guide tube.
Pull out oil dipstick1 again after
approximately 3 seconds to obtain
accurate reading.
The oil level is correct when it is between
lower mark 3 (min.) and upper mark 2
(max.) of the oil dipstick.
!Excess oil must be siphoned or drained off.
It could cause damage to the engine and/or
catalytic converter (gasoline engine) or the
oxidation catalyst (diesel engine) not covered by
the Mercedes-Benz Limited Warranty.
Page 370 of 570

369 Operation
Engine compartment
If necessary, add engine oil.
For more information on engine oil, see
“Technical data” section (
page 538) and
(
page 540).
For information on messages in the multi-
function display concerning engine oil, see
the “Practical hints” section (
page 459).Adding engine oil
R 350 (R 320 CDI similar)
1Filler cap
R 500 (R 63 AMG similar)
1Filler cap
iAll models (except R 63 AMG):
The filling quantity between the upper and
lower marks on the oil dipstick is approximately
2.1 US qt (2.0 l).
R 63 AMG:
The filling quantity between the upper and
lower marks on the oil dipstick is approximately
1.6 US qt (1.5 l).
!Only use approved engine oils and oil filters
required for vehicles with Maintenance System
(U.S. vehicles) or FSS PLUS (Canada vehicles).
For a listing of approved engine oils and oil
filters, refer to the Factory Approved Service
Products pamphlet in your vehicle literature port-
folio, or contact an authorized Mercedes-Benz
Light Truck Center.
Using engine oils and oil filters of specification
other than those expressly required for the
Maintenance System (U.S. vehicles) or
FSS PLUS (Canada vehicles), or changing of oil
and oil filter at change intervals longer than
those called for by the Maintenance System
(U.S. vehicles) or FSS PLUS (Canada vehicles)
will result in engine or emission control system
damage not covered by the Mercedes-Benz
Limited Warranty.
Page 371 of 570

370 Operation
Engine compartment
Unscrew filler cap1 from filler neck.
Add engine oil as required. Be careful
not to overfill 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 538) and
(
page 540).
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.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.
!Excess oil must be siphoned or drained off.
It could cause damage to the engine or
emission control system not covered by the
Mercedes-Benz Limited Warranty.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.
Page 372 of 570
371 Operation
Engine compartment
The coolant expansion tank is located on
the passenger side of the engine compart-
ment.
1Cap
2Coolant expansion tank
3Indicator wall
4Coolant levelUsing 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
“Coolants” (
page 543).
Using a rag, slowly open the cap approx-
imately 1/2turn 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.
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372 Operation
Engine compartment
Windshield/rear window washer
system and headlamp cleaning*
system
The windshield washer reservoir is located
in the engine compartment.
1Cap
2Windshield washer reservoirFluid 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 “MB SummerFit” 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 “MB SummerFit”
and water (or commercially available
premixed windshield washer sol-
vent/antifreeze, depending on ambient
temperatures).
For more information, see “Windshield and
headlamp washer fluid mixing ratio”
(
page 546).
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.
!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.
!Only use washer fluid which is suitable for
plastic lenses. Improper washer fluid can
damage the plastic lenses of the headlamps.
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373 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.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
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.
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374 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 380).Tire inspection
Every time you check your tire inflation
pressure, you should also inspect your
tires for the following:
excessive treadwear (page 375)
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.
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375 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
1/16in (1.6 mm), at which point the
tire is considered worn and should be re-
placed.
Recommended minimum tire tread depth:
Summer tires 1/8in (3 mm)
Winter tires 1/6in (4 mm)
1TWI (T
read Wear Indicator)
The treadwear indicator appears as a solid
band across the tread.Storing tires
Cleaning tires
Direction 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.
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 ap-
proaches 1/8in (3 mm), the adhesion prop-
erties on a wet road are sharply reduced.
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
fuels.
!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.