2008 MERCEDES-BENZ SLK350 Owner's Manual

296 Operation
Engine compartment
Engine oil
The amount of oil your engine needs will
depend on a number of factors, including
driving style. Higher oil consumption can
occur when

the vehicle is new

the vehicle is driven frequently at
higher engine speeds
Engine oil consumption checks should only
be made after the vehicle break-in period.Checking engine oil level with the
control system (SLK 55 AMG only)
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 sta-
tionary for at least 5 minutes with the
engine turned off.

with the engine not at operating tem-
perature, the vehicle must have been
stationary for at least 30 minutes with
the engine turned off.To check the engine oil level via the
multifunction display, do the following:
Switch on the ignition (page 37).
The standard display appears in the
multifunction display (
page 127).
Press buttonk orj on the mul-
tifunction steering wheel repeatedly
until the following message appears in
the multifunction display (
page 122):
!Do not use any special lubricant additives,
as these may damage the drive assemblies.
Using special additives not approved by
Mercedes-Benz may cause damage not covered
by the Mercedes-Benz Limited Warranty.
More information on this subject is available at
any authorized Mercedes-Benz Center.

297 Operation
Engine compartment
One of the following messages will
subsequently appear in the multifunc-
tion display:

Engine Oil Level
OK

Add 1.0 qt. (Canada: 1.0 liter)
to reach max. oil level.

Add 1.5 qts. (Canada:
1.5 liters)
to reach max. oil level.

Add 2.0 qts. (Canada:
2.0 liters)
to reach max. oil level.
If necessary, add engine oil.
For adding engine oil, see “Adding
engine oil” (
page 299).
For more information on engine oil, see
“Fuels, coolants, lubricants, etc.”
(
page 451).Other display messages
If the ignition is not switched on, the fol-
lowing message will appear:
Turn on ignition
to see engine oil level
.
Switch on the ignition (page 37).
If you see the message:
Observe
Waiting Time
If engine is at operating temperature,
wait 5 minutes before repeating check
procedure.
If engine is not at operating tempera-
ture yet, you must wait 30 minutes
before checking oil.If you see the message:
Cannot check engine oil level
with engine on.
Turn off the engine.
If the engine is at operating tempera-
ture, wait 5 minutes before checking
oil.
If the engine is not at operating
temperature yet, you must wait
30 minutes before checking oil.
iIf you want to interrupt the checking
procedure, press buttonk orj on the
multifunction steering wheel (
page 122).
iIf you want to interrupt the checking
procedure, press buttonk orj on the
multifunction steering wheel (
page 122).

298 Operation
Engine compartment
If there is excess engine oil with the engine
at normal 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 Center.
For more information on messages in the
display concerning engine oil, see the
“Practical hints” section (
page 360).Checking engine oil level with the oil
dipstick (SLK 280, SLK 350 only)
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, the vehicle must have been
stationary for at least 30 minutes with
the engine turned off.1Oil dipstick
2Upper (max) mark
3Lower (min) mark
To check the engine oil level with the oil
dipstick, do the following:
Open the hood (page 294).
Pull out oil dipstick1.
Wipe oil dipstick1 clean.
Fully insert oil dipstick1 into the
dipstick guide tube.
!Excess oil must be siphoned or drained off.
It could cause damage to the engine and
catalytic converter not covered by the
Mercedes-Benz Limited Warranty.

299 Operation
Engine compartment
Pull out oil dipstick1 again after
approximately 3 seconds to obtain
accurate reading.
The oil level is correct when it is be-
tween the lower (min) mark3 and
upper (max) mark2 of oil dipstick1.
If necessary, add engine oil.
For adding engine oil, see “Adding
engine oil” (
page 299).
For more information on engine oil, see
“Fuels, coolants, lubricants, etc.”
(
page 451).
For more information on messages in the
multifunction display concerning engine
oil, see the “Practical hints” section
(
page 360).Adding engine oil
SLK 350 (example illustration)
1Filler cap
SLK 55 AMG
1Filler cap
iThe filling quantity between the upper and
lower marks on the oil dipstick is approximately
2.1 US qt. (2.0 l).
!Only use approved engine oils and oil filters
required for vehicles with Maintenance System.
For a listing of approved engine oils and oil
filters, refer to the Factory Approved Service
Products pamphlet (USA only) in your vehicle
literature portfolio, or contact an authorized
Mercedes-Benz Center.
Using engine oils and oil filters of specification
other than those expressly required for the
Maintenance System, or changing of oil and oil
filter at change intervals longer than those called
for by the Maintenance System will result in
engine or emission control system damage not
covered by the Mercedes-Benz Limited
Warranty.

300 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” (
page 451) and
(
page 453).
Transmission fluid level*
Vehicles with automatic transmission*:
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 Center
check the transmission.
Coolant level
The engine coolant is a mixture of water
and anticorrosion/antifreeze.
When checking the coolant level,

the vehicle must be parked on level
ground

the coolant temperature must be
below 158°F (70°C)
!Excess oil must be siphoned or drained off.
It could cause damage to the engine and
emission control system not covered by the
Mercedes-Benz Limited Warranty.
Warning!G
In order to avoid any potentially 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 1/2turn to relieve excess pres-
sure. If opened immediately, scalding
hot fluid and steam will be blown out
under pressure.

Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene
glycol which may burn if it comes into
contact with hot engine parts.

301 Operation
Engine compartment
The coolant expansion tank is located on
the passenger side of the engine compart-
ment.
SLK 350 (example illustration)
1Coolant expansion tank
2Cap
3Marking bar in the expansion tank
Using a rag, turn cap2 slowly approx-
imately one half turn counterclockwise
to release any excess pressure.
Continue turning cap2 counterclock-
wise and remove it.
The coolant level is correct if the level

for cold coolant: reaches marking
bar3 in expansion tank1

for warm coolant: is approximately
0.6 in (1.5 cm) higher
Add coolant as required.
Replace and tighten cap2.
For more information on coolant, see
“Coolants” (
page 456).Windshield washer system and
headlamp cleaning system*
The windshield washer reservoir is located
on the passenger side of the engine com-
partment.
SLK 350 (example illustration)
1Cap for windshield 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
approximately 7.4 US qt (7 l).

302 Operation
Engine compartment
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 cap 1 upwards.
Refill the reservoir with MB Windshield
Washer Concentrate “MB SummerFit”
and water (or commercially available
premixed windshield washer
solvent/antifreeze, depending on
ambient temperatures).
For more information, see “Windshield
washer system and headlamp cleaning
system*” (
page 458).
Battery
Your vehicle’s battery is located in the en-
gine compartment.
The battery should always be sufficiently
charged in order to achieve its rated ser-
vice life. Refer to the Maintenance Booklet
for battery maintenance intervals.
If you use your vehicle mostly for
short-distance trips, you will need to
have the battery charge checked more
frequently.
When replacing the battery, always use
batteries approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, consult an
authorized Mercedes-Benz Center about
steps you need to observe.
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 dam-
age the plastic lenses of the headlamps.

303 Operation
Engine compartment
Batteries contain materials that can harm
the environment if disposed of improperly.
Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.
Warning!G
Observe all safety instructions and precau-
tions when handling automotive batteries.
Risk of explosion.
Fire, open flames and smoking
are prohibited when handling
batteries. Avoid creating sparks.
Battery acid is caustic. Do not
allow it to come into contact
with skin, eyes or clothing.
Wear suitable protective cloth-
ing, especially gloves, apron and
faceguard.
Wear eye protection.
Rinse any acid spills immediate-
ly with clear water. Contact a
physician if necessary.
Keep children away.
Follow the instructions in this
Operator’s Manual.