311 Operation
Engine compartment
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 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.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 307).
Pull out oil dipstick1.
Wipe oil dipstick1 clean.
Fully insert oil dipstick1 into the
dipstick guide tube.
Pull out oil dipstick1 again after
approximately 3 seconds to obtain ac-
curate 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 en-
gine oil” (
page 312).
For more information on engine oil, see
“Fuels, coolants, lubricants, etc.”
(
page 449).
For more information on messages in the
multifunction display concerning engine
oil, see the “Practical hints” section
(page 368).iThe filling quantity between the upper
and lower marks on the oil dipstick is
approximately 2.1 US qt. (2.0 l).
312 OperationEngine compartmentAdding engine oil
Only use approved engine oils and oil fil-
ters 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
portfolio, or contact an authorized
Mercedes-Benz Center.
Using engine oils and oil filters of specifica-
tion other than those expressly required
for the Maintenance System (U.S. vehi-
cles) or FSS PLUS (Canada vehicles), or
changing of oil and oil filter at change inter-
vals longer than those called for by the
Maintenance System (U.S. vehicles) or
FSS PLUS (Canada vehicles) will result in
engine damage not covered by the
Mercedes-Benz Limited Warranty.
SLK 350 (example)1Filler capSLK 55 AMG1Filler cap
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 449) and
(
page 451).!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.
352 OperationMaintenance
Resetting the maintenance service indicator
In the event that the maintenance service
on your vehicle is not carried out by an au-
thorized Mercedes-Benz Center, you can
have the maintenance service indicator re-
set. The automotive maintenance facility
carrying out the maintenance service will
find the information for resetting the main-
tenance service indicator in the mainte-
nance-relevant information for your
vehicle. Such information is available from
either your authorized Mercedes-Benz
Center or directly from Mercedes-Benz.
iIf the battery is disconnected, the days
of disconnection will not be included in
the count shown by the maintenance
service indicator. To arrive at the true
maintenance service deadline, you will
need to subtract these days from the
days shown in the maintenance service
indicator.
Do not confuse the maintenance ser-
vice indicator with the engine oil level
indicatorN.
iIf the maintenance service indicator
was inadvertently reset, have an autho-
rized Mercedes-Benz Center correct it.
Only reset if the proper maintenance
service has been performed. Resetting
the system without performing the
proper maintenance service as called
for by the maintenance service indica-
tor will result in engine damage and/or
other vehicle damage not covered by
the Mercedes-Benz Limited Warranty.
379 Practical hints
What to do if …
When the message
Add 1 qt.
(Canada:
1 liter
) engine oil when next
refueling (SLK 55 AMG) or
Check oil
level when next refueling (SLK 280,
SLK 350) appears while the engine is run-
ning and at operating temperature, the en-
gine oil level has dropped to approximately
the minimum level.When this occurs, the warning will first
come on intermittently and then stay on if
the oil level drops further.
Visually check for oil leaks. If no obvious oil
leaks are noted, drive to the nearest ser-
vice station where the engine oil should be
topped to the required level with an ap-
proved oil specified in the Factory
Approved Service Products pamphlet.
Display symbol
Display message
Possible cause/consequence
Possible solution
N
Check oil level
when next refueling
SLK 280 and SLK 350 only:
The engine oil level has dropped to
a critical level.
Check the engine oil level (
page 308) and
add engine oil as required (page 312).
If you must add engine oil frequently, have
the engine checked for possible leaks.
USA only:Add 1 qt. engine oil
when next refuelingCanada only:Add 1 liter engine oil
when next refueling
SLK 55 AMG only:
The engine oil level is too low.
Add engine oil (
page 312) and check the
engine oil level (page 308).
!The engine oil level warnings should
not be ignored. Extended driving with
the symbol displayed could result in
serious engine damage that is not
covered by the Mercedes-Benz Limited
Warranty.
380 Practical hintsWhat to do if …Display symbol
Display message
Possible cause/consequence
Possible solution
N
Engine oil level
Stop, engine off
SLK 55 AMG only:
There is no oil in the engine. There
is a danger of engine damage.
Carefully bring the vehicle to a halt as soon
as possible.
Turn off the engine.
Add engine oil (
page 312) and check the
engine oil level (page 308).
Engine oil level
Visit workshop
SLK 55 AMG only:
The measuring system is malfunc-
tioning.
Have the measuring system checked by an
authorized Mercedes-Benz Center.
Engine oil level
Reduce oil level
SLK 55 AMG only:
You have added too much engine
oil. There is a risk of damaging the
engine or the catalytic converter.
Have oil siphoned or drained off.
Observe all legal requirements with respect
to its disposal.
Engine oil
Visit workshop
SLK 55 AMG only:
There may be water in the engine
oil.
Have the engine oil checked.
449 Technical data
Fuels, coolants, lubricants, etc.
Fuels, coolants, lubricants, etc.
CapacitiesVehicle components and their respective
lubricants must match. Therefore, only use
products tested and approved by
Mercedes-Benz.Please refer to the Factory Approved
Service Products pamphlet, or inquire at
your authorized Mercedes-Benz Center.
Model
Capacity
Fuels, coolants, lubricants etc.
Engine with oil filter
SLK 280, SLK 350
8.5 US qt (8.0 l)
Approved engine oils
SLK 55 AMG
8.5 US qt (8.0 l)
Automatic transmission*
SLK 280, SLK 350
10.4 US qt (9.8 l)
MB Automatic Transmission Fluid
SLK 55 AMG
10.4 US qt (9.8 l)
Manual transmission
SLK 280, SLK 350
1.6 US qt (1.5 l)
MB Manual Transmission Oil
Rear axle
SLK 280
1.1 US qt (1.0 l)
Hypoid gear oil SAE 85 W 90
SLK 350
1.2 US qt (1.1 l)
SLK 55 AMG
1.3 US qt (1.2 l)
Power steering
SLK 280, SLK 350
1.1 US qt (1.0 l)
MB Power Steering Fluid (Pentosin CHF 11S)
SLK 55 AMG
1.1 US qt (1.0 l)
Front wheel hubs
approx. 2.1oz (60g) each
High temperature roller bearing grease
Brake system
0.5 US qt (0.5 l)
MB Brake Fluid (DOT 4+)
451 Technical data
Fuels, coolants, lubricants, etc.
Engine oils
Engine oils are specifically tested for their
suitability in our engines and durability for
our service intervals. Therefore, only use
approved engine oils and oil filters re-
quired for vehicles with Maintenance
System (U.S. vehicles) or FSS PLUS (Cana-
da vehicles). For a listing of approved en-
gine oils and oil filters, refer to the Factory
Approved Service Products pamphlet, or
contact an authorized Mercedes-Benz
Center.
Engine oil additives
Do not blend oil additives with engine oil.
They may damage the engine. Damage or
malfunctions resulting from blending oil
additives are not covered by the
Mercedes-Benz Limited Warranty.Air conditioning refrigerant
R-134a (HFC) refrigerant and special
PAG lubricating oil are used in the air con-
ditioning system. Never use R-12 (CFC) or
mineral-based lubricating oil, otherwise
damage to the system will occur.
Brake fluid
During vehicle operation, the boiling point
of the brake fluid is continuously reduced
through the absorption of moisture from
the atmosphere.
Only brake fluid approved by
Mercedes-Benz is recommended. Your au-
thorized Mercedes-Benz Center will pro-
vide you with additional information.
!Using engine oils and oil filters of spec-
ification other than those expressly re-
quired 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 damage
not covered by the Mercedes-Benz
Limited Warranty.
Please follow Maintenance System
(U.S. vehicles) or FSS PLUS (Canada
vehicles) recommendations for sched-
uled oil changes. Failure to do so will
result in engine damage not covered by
the Mercedes-Benz Limited Warranty.
Warning!
G
Under extremely strenuous operating condi-
tions, this moisture content can lead to the
formation of bubbles in the system, thus re-
ducing the system’s efficiency.
Therefore, the brake fluid must be replaced
regularly. Refer to your vehicle’s
Maintenance Booklet for replacement
interval.
452 Technical dataFuels, coolants, lubricants, etc.Premium unleaded gasoline
Fuel requirements
Only use premium unleaded fuel:
The octane number (posted at the
pump) must be 91 min. It is an average
of both the Research (R) octane num-
ber and the Motor (M) octane number:
(R+M) / 2). This is also known as the
ANTI-KNOCK INDEX.
Unleaded gasoline containing oxygenates
such as ethanol, IPA, IBA, and TBA can be
used provided the ratio of any one of these
oxygenates to gasoline does not exceed
10%; MTBE not to exceed 15%.
The ratio of methanol to gasoline must not
exceed 3% plus additional cosolvents.
Using mixtures of ethanol and methanol is
not allowed. Gasohol, which contains
10% ethanol and 90% unleaded gasoline,
can be used.
These blends must also meet all other fuel
requirements, such as resistance to spark
knock, boiling range, vapor pressure, etc.
Warning!
G
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious inju-
ry. Whenever you are around gasoline, avoid
inhaling fumes and skin contact, extinguish
all smoking materials. Never allow sparks,
flame or smoking materials near gasoline!
!To maintain the engine’s durability and
performance, premium unleaded gaso-
line must be used. If premium unleaded
is not available and low octane fuel is
used, follow these precautions:
Have the fuel tank only partially
filled with unleaded regular and fill
up with premium unleaded as soon
as possible.
Avoid full throttle driving and abrupt
acceleration.
Do not exceed an engine speed of
3 000 rpm if the vehicle is loaded
with a light load such as two per-
sons and no luggage.
Do not exceed
2/3of maximum ac-
celerator pedal position if the vehi-
cle is fully loaded or operating in
mountainous terrain.