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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
R134a (HFC) refrigerant and special PAG
lubricating
oil are used in the air conditioning
system.
! Never use R 12 (CFC) or mineral-based
lubricating oil. Otherwise damage to the
system will occur. Brake fluid
G
Warning!
During vehicle operation, the boiling point of
the brake fluid is continuously reduced
through the absorption of moisture from the
atmosphere.
Under extremely strenuous operating
conditions, this moisture content can lead to
the formation of bubbles in the system, thus
reducing the system’s efficiency.
Therefore, the brake fluid must be replaced
regularly.
Refer to your vehicle’s Maintenance
Booklet for replacement interval.
Only brake fluid approved by Mercedes-Benz
is recommended. Any authorized Mercedes-
Benz Center will provide you with additional
information. Premium unleaded gasoline
G
Warning!
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious
personal injury. Never allow sparks, flames or smoking
materials near gasoline!
Turn off the engine before refueling.
Whenever you are around gasoline, avoid
inhaling fumes and any skin or clothing
contact. Extinguish all smoking materials.
Direct skin contact with fuels and the
inhalation of fuel vapors are damaging your
health.
! To maintain the engine’s durability and
performance, premium unleaded gasoline
must be used.
If premium unleaded gasoline is not
available and low octane gasoline is used,
follow these precautions:
R Have the fuel tank only partially filled
with
unleaded regular gasoline and fill up
with premium unleaded gasoline as soon
as possible.
R Avoid full throttle driving and abrupt
acceleration.
R Do not exceed an engine speed of
3 000 rpm if the vehicle is loaded with a
light load such as two persons and no
luggage.
R Do not exceed 2
/ 3 of maximum
accelerator pedal position if the vehicle
is fully loaded or operating in
mountainous terrain. Fuel requirements
Only use premium unleaded gasoline. The
octane
number (posted at the pump) must be
91 min. It is an average of both the Research
Octane Number (RON) and the Motor Octane
Number (MON): (RON+MON)/2. This is also
known as the ANTI-KNOCK INDEX.
Reformulated gasolines (RFG) and/or
unleaded gasoline containing oxygenates
such as ethanol, TAME, ETBE, IPA, IBA, and
TBA can be used provided the ratio of any one Fuels, coolants, lubricants, etc.
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of these oxygenates to gasoline does not
exceed 10%; MTBE must not 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. Gasoline additives
A major concern among engine
manufacturers is carbon build-up caused by
gasoline. Mercedes-Benz recommends only
the use of quality gasoline containing
additives that prevent the build-up of carbon
deposits.
After an extended period of using fuels
without such additives carbon deposits can
build up, especially on the intake valves and
in the combustion area, leading to engine
performance problems such as:
R Warm-up hesitation
R Unstable idle
R Knocking/pinging
R Misfire
R Power loss
In areas where carbon deposits may be
encountered due to lack of availability of
gasoline which contains these additives, the
use of Mercedes-Benz approved additives is
recommended.
Contact
an authorized Mercedes-Benz Center
or visit www.mbusa.com (USA only) for a
listing of approved products. Follow
directions on the product label.
Do not blend other fuel additives with fuel.
This only results in unnecessary cost and may
be harmful to the engine operation. !
Damage or malfunction resulting from
poor
fuel quality or from blending additional
fuel additives other than those tested and
approved by us for use on Mercedes-Benz
vehicles are not covered by the Mercedes-
Benz Limited Warranty or by any pre-owned
or Extended Limited Warranties. Coolants
The engine coolant is a mixture of water and
anticorrosion/antifreeze, which provides:
R Corrosion protection
R Freeze protection
R Boiling
protection (by increasing the boiling
point)
The cooling system was filled at the factory
with a coolant providing freeze protection to
approximately -35‡ (-37†) and corrosion
protection.
! Add premixed coolant solution only.
Adding water and MB 325.0 Anticorrosion/
Antifreeze separately from each other,
could cause engine damage not covered by
the Mercedes-Benz Limited Warranty.
If the antifreeze mixture is effective to -35‡
(-37†), the boiling point of the coolant in the
pressurized cooling system is reached at
approximately 266‡ (130†).
The coolant solution must be used year round
to provide the necessary corrosion protection
and increase boil-over protection. Refer to
the Maintenance Booklet for replacement
interval.
Coolant system design and coolant used
determine the replacement interval. The
replacement interval published in the
Maintenance Booklet is only applicable if
MB 325.0 Anticorrosion/Antifreeze solution
or other Mercedes-Benz approved products
of equal specification are used to renew the
coolant concentration or bring it back up to
the proper level. 304
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For information on other Mercedes-Benz
approved products of equal specification,
contact
an authorized Mercedes-Benz Center
or visit www.mbusa.com (USA only).
To provide important corrosion protection,
the solution must be at least 50%
anticorrosion/antifreeze (equivalent to
freeze protection to approximately -35‡
[-37†]).
If you use a solution that is more than 55%
anticorrosion/antifreeze (freeze protection
to approximately -49‡ [-45†]), the engine
temperature will increase due to the lower
heat transfer capability of the solution.
Therefore, do not use more than this amount
of anticorrosion/antifreeze.
If the coolant level is low, water and MB 325.0
Anticorrosion/Antifreeze should be used to
bring it up to the proper level (have cooling
system checked for signs of leakage). Please
make sure the mixture is in accordance with
label instructions.
The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water. If you are not sure about the water quality,
contact an authorized Mercedes-Benz
Center.
Anticorrosion/antifreeze Your vehicle contains a number of aluminum
parts. The use of aluminum components in
motor vehicle engines necessitates that
anticorrosion/antifreeze coolant used in
such engines be specifically formulated to
protect the aluminum parts. Failure to use
such anticorrosion/antifreeze coolant will
result
in a significantly shortened service life.
Therefore, the following product is strongly
recommended for use in your vehicle:
MB 325.0 Anticorrosion/Antifreeze agent.
Before the start of the winter season (or once
a year in hot southern regions), you should
have the anticorrosion/antifreeze
concentration checked.
The coolant is also regularly checked each
time you bring your vehicle to an authorized
Mercedes-Benz Center for service. Model Approximate freeze protection
-35‡ (-37†) -49‡ (-45†)
Cooling system
SLK 300
SLK 350 5.2 US qt (4.9 l) 5.7 US qt (5.4 l)
SLK 55 AMG 5.9 US qt (5.55 l) 6.5 US qt (6.1 l)Fuels, coolants, lubricants, etc.
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Washer system and headlamp
cleaning system
G
Warning!
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.
X Use MB Windshield Washer Concentrate
“MB SummerFit”.
X Mix with water for temperatures above
freezing point.
X Mix with commercially available premixed
washer solvent/antifreeze for
temperatures below freezing point.
Washer fluid mixing ratio For temperatures above the freezing point:
1 part “MB SummerFit” to 100 parts water
(1.34 fl oz [40 ml] “MB SummerFit” to 1 gal
[4.0 l] water)
For temperatures below freezing point:
1 part “MB SummerFit” to 100 parts solvent
(1.34 fl oz [40 ml] “MB SummerFit” to 1 gal
[4.0 l] solvent)306
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Service and Literature
Your authorized Mercedes-Benz Center has
trained technicians and Genuine Mercedes-
Benz Parts to service your vehicle properly.
For
expert advice and quality service, contact
an authorized Mercedes-Benz Center.
If you are interested in obtaining service
literature for your vehicle, please contact an
authorized Mercedes-Benz Center.
We consider this the best way for you to
obtain accurate information for your vehicle.
For further information you can find us on the
Mercedes-Benz web site www.mbusa.com
(USA only) or www.mercedes-benz.ca
(Canada only). G
Warning!
To help avoid personal injury, be extremely
careful when performing any service work or
repairs.
Improper or incomplete service or the
use of incorrect or inappropriate parts or
materials may damage the vehicle or its
equipment, which may in turn result in
personal injury.
If you have any questions about carrying out
any type of service, turn to the advice of an
authorized Mercedes-Benz Center.
We reserve the right to make changes in
design and equipment.
Therefore, information, illustrations and
descriptions in this Operator’s Manual might
differ from your vehicle.
Reprinting, translation and copying, even of
excerpts, is not permitted without our prior
authorization in writing.
Press time May 13, 2009
GSP/OIS
Printed in U. S. A.
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Order no. 6515 3297 13Part no. 171 584 27 96Edition A 2010
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