
Rusing a rag, slowly turn the cap
approximately 1
/ 2 turn to relieve excess
pressure. If opened immediately, scalding
hot fluid and steam will be blown out under
pressure.
R do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts.XPark the vehicle on a level surface.
Only check the coolant level when the
vehicle is on a level surface and the engine
has cooled down.XTurn the SmartKey to position 2 in the
ignition lock ( Y page 131).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice ( Y page 131).XCheck the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
158 ‡ (70 †).XTurn the SmartKey to position
0 (Y page 131) in the ignition lock.XSlowly turn cap ; half a turn counter-
clockwise to allow excess pressure to
escape.XTurn cap ; further counter-clockwise and
remove it.
If the coolant is at the level of marker bar
= in the filler neck when cold, there is
enough coolant in coolant expansion
tank :.
If the coolant level is approximately 0.6 in
(1.5 cm) above marker bar = in the fillerneck when warm, there is enough coolant
in coolant expansion tank :.XIf necessary, add coolant that has been
tested and approved by Mercedes-Benz.XReplace cap ; and turn it clockwise as far
as it will go.
For further information on coolant, see
( Y page 327).
Adding washer fluid to the windshield
washer system/headlamp cleaning
system
GWARNING
Washer solvent/antifreeze is highly
flammable. Do not spill washer solvent/
antifreeze on hot engine parts, because it may
ignite and burn. You could be seriously
burned.
XTo open: pull cap : upwards by the tab.XAdd the premixed washer fluid.XTo close: press cap : onto the filler neck
until it engages.
The washer fluid reservoir is used for both the
windshield washer system and the headlamp
cleaning system.
Further information on windshield washer
fluid/antifreeze ( Y page 328).
Brake fluid level
! If the brake fluid level in the brake fluid
reservoir has fallen to the MIN mark or
below, check the brake system
Engine compartment263Maintenance and careZ

In addition to being stamped on the vehicle
identification plate, the vehicle identification
number (VIN) is also stamped onto the vehicle
body.
It is located in the transmission tunnel on the
front-passenger side.XSlide the front-passenger seat to its
frontmost position.XFold trim : upwards.
You will see vehicle identification number
(VIN) ;.
Engine number
:Emission control information plate,
including the certification of both federal
and Californian emissions standards;Engine number (stamped into the
crankcase)=VIN (on the lower edge of the windshield)Service products and filling
capacities
Important safety notes
GWARNING
Comply with all valid regulations with respect
to handling, storing and disposing of service
fluids. Otherwise, you could endanger
persons or the environment.
Keep service fluids out of the reach of
children.
For health reasons, you should prevent
service fluids from coming into direct contact
with your skin or clothing.
If a service fluid is swallowed, contact a
physician immediately.
Service products include the following:
R fuels
R lubricants (e.g. engine oil, transmission oil)
R coolant
R brake fluid
R windshield washer fluid
R climate control system refrigerant
Vehicle components and their service
products must match. Therefore only use
products tested and approved by Mercedes-
Benz.
Information about tested and approved
products can be obtained from an authorized
Mercedes-Benz Center or on the Internet at
http://bevo.mercedes-benz.com.
You can recognize service products approved
by Mercedes-Benz by the following
inscription on the containers:
R MB-Freigabe (e.g. MB-Freigabe 229.51)
R MB Approval (e.g. MB Approval 229.51)
Other designations or recommendations
indicate a level of quality or a specification in
accordance with an MB Sheet number (e.g.
MB 229.5). They have not necessarily been
approved by Mercedes-Benz.
324Service products and filling capacitiesTechnical data

Filling capacities
The following values refer to an oil change
including the oil filter.
ModelCapacitySLK 2505.8 US qt (5.5 l)SLK 3506.9 US qt (6.5 l)SLK 55 AMG10.0 US qt (9.5 l) 24
Additives
!
Do not use any additives in the engine oil.
This could damage the engine.
Engine oil viscosity
Viscosity describes the flow characteristics
of a fluid. If an engine oil has a high viscosity,
this means that it is thick; a low viscosity
means that it is thin.
Select an engine oil with an SAE (viscosity)
classification suitable for the prevailing
outside temperatures. The table shows you
which SAE classifications are to be used. The
low-temperature characteristics of engine
oils can deteriorate significantly, e.g. as a
result of aging, soot and fuel deposits. It is
therefore strongly recommended that you
carry out regular oil changes using an
approved engine oil with the appropriate SAE
classification.
Brake fluidGWARNING
Over a period of time, the brake fluid absorbs
moisture from the air; this lowers its boiling
point.
If the boiling point of the brake fluid is too low,
vapor pockets may form in the brake system
when the brakes are applied hard (e.g. when
driving downhill). This would impair braking
efficiency.
You should have the brake fluid renewed at
regular intervals. The brake fluid change
intervals can be found in the Maintenance
Booklet.
Only use brake fluid approved by Mercedes-
Benz. Information about approved brake fluid
can be obtained at any qualified specialist
workshop or on the Internet at
http://bevo.mercedes-benz.com.
Coolant
Important safety notes
GWARNING
Antifreeze is highly flammable. Fire, naked
flames and smoking are prohibited when
handling antifreeze.
If antifreeze comes into contact with hot
engine parts, it may ignite and you could burn
yourself. Do not spill any antifreeze on hot
engine parts.
! Only add coolant that has been premixed
with the desired antifreeze protection. You
could otherwise damage the engine.
Further information on coolants can be
found in the Mercedes-Benz Specifications
for Service Products, MB Specifications for
Service Products 310.1, e.g. on the
Internet at
http://bevo.mercedes-benz.com. Or
contact a qualified specialist workshop.
24 Including external oil cooler.Service products and filling capacities327Technical dataZ

! Always use a suitable coolant mixture,
even in countries where high temperatures
prevail.
Otherwise, the engine cooling system is not
sufficiently protected from corrosion and
overheating.
The coolant is a mixture of water and
antifreeze/corrosion inhibitor. It performs
the following tasks:
R corrosion protection
R antifreeze protection
R raising the boiling point
If the coolant has antifreeze protection down
to -35 ‡ (-37 †), the boiling point of the
coolant under operating conditions is
approximately 266 ‡ (130 †).
The antifreeze/corrosion inhibitor
concentration in the engine cooling system
should:
R be at least 50 %. This will protect the engine
cooling system against freezing down to
approximately -35 ‡ (-37 †).
R not exceed 55% (antifreeze protection
down to -49 ‡ [-45 †]). Otherwise, heat
will not be dissipated as effectively.
If the vehicle has lost coolant, add equal
amounts of water and antifreeze/corrosion
inhibitor. Mercedes-Benz recommends an
antifreeze/corrosion inhibitor concentrate in
accordance with MB Specifications for
Service Products 310.1.
The coolant is checked with every
maintenance interval at a qualified specialist
workshop.
i When the vehicle is first delivered, it is
filled with a coolant mixture that ensures
adequate antifreeze and corrosion
protection.CapacityModelCapacitySLK 250Approx. 10.1 US qt (9.6 l)SLK 350Approx. 11.0 US qt(10.4 l)SLK 55 AMGApprox. 10.0 US qt (9.5 l)
iUse MB 325.0 or MB 326.0 corrosion
inhibitor/antifreeze.
Washer fluid
GWARNING
Washer solvent/antifreeze is highly
flammable. 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 that is suitable for
plastic lamp lenses, e.g. MB SummerFit or
MB WinterFit. Unsuitable washer fluid
could damage the plastic lenses of the
headlamps.
! Do not add distilled or de-ionized water to
the washer fluid container. Otherwise, the
level sensor may be damaged.
! Only MB SummerFit and MB WinterFit
washer fluid should be mixed together. The
spray nozzles may otherwise become
blocked.
At temperatures above freezing:
XFill the washer fluid reservoir with a mixture
of water and windshield washer fluid, e.g.
MB SummerFit.XAdd 1 part MB SummerFit to 100 parts
water.328Service products and filling capacitiesTechnical data