Page 449 of 481

448 Technical data
Fuels, coolants, lubricants, etc.
Capacities
Vehicle components and their respective
lubricants must match. Therefore only use
products tested and approved by
Mercedes-Benz.
Please refer to the Factory Approved Ser-
vice Products pamphlet, or inquire at your
Mercedes-Benz Center.
Warning!G
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 eyes or any open wounds.
If a service fluid is swallowed, contact a
physician immediately.
ModelCapacityFuels, coolants, lubricants, etc.
Engine with oil filterCLK 350
CLK 5508.5 US qt (8.0 l)
9.0 US qt (8.5 l)Approved engine oils
Automatic transmissionCLK 350
CLK 5509.0 US qt (8.5 l)
9.5 US qt (9.0 l)MB Automatic Transmission Fluid
Rear axleCLK 350
CLK 5501.16 US qt (1.1 l)
1.27 US qt (1.2 l)Hypoid gear oil SAE 85 W 90
Power steeringapprox. 1.1 US qt (1.0 l)MB Power Steering Fluid (Pentosin
CHF 11S)
Front wheel hubsapprox. 3.0 oz (85 g) eachHigh temperature roller bearing grease
Brake system0.64 US qt (0.6 l)MB Brake Fluid (DOT 4+)
Page 450 of 481
449 Technical data
Fuels, coolants, lubricants, etc.
ModelCapacityFuels, coolants, lubricants, etc.
Cooling systemCLK 350
CLK 550approx. 7.8 US qt (7.4 l)
approx. 9.7 US qt (9.2 l)MB 325.0 Anticorrosion/Antifreeze
Agent
Fuel tank
including a reserve of16.35 US gal (62.0 l)
2.11 US gal (8.0 l)Premium unleaded gasoline:
Minimum Posted Octane 91
(Avg.of96RON/86MON)
Air conditioning systemR-134a refrigerant and special PAG lu-
bricant oil (never R-12)
Windshield washer and
headlamp cleaning system*6.4 US qt (6.0 l)MB Windshield Washer Concentrate1
1Use MB Windshield Washer Concentrate “MB SummerFit” and water for temperatures above freezing point or MB Windshield Washer Concentrate “MB SummerFit”
and commercially available premixed windshield washer solvent / antifreeze for temperatures below freezing point. Follow suggested mixing ratios (page 455).
Page 451 of 481

450 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 (Canada
vehicles). For a listing of approved engine
oils and oil filters, refer to the Factory Ap-
proved 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
conditioning 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. An
authorized Mercedes-Benz Center will
provide you with additional information.
!Using engine oils and oil filters of specifica-
tion other than those expressly required for the
Maintenance System (U.S. vehicles) or FSS
(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 (Canada vehicles) will result in engine or
emission control system damage not covered by
the Mercedes-Benz Limited Warranty. Please follow Maintenance System
(U.S. vehicles) or FSS (Canada vehicles) recom-
mendations for scheduled oil changes. Failure to
do so will result in engine or emission control
system 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 Mainte-
nance Booklet for replacement interval.
Page 452 of 481

451 Technical data
Fuels, coolants, lubricants, etc.
Premium unleaded gasolineFuel 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 per-
sonal injury.
Never allow sparks, flame or smoking mate-
rials near gasoline!
Turn off the engine before refueling
Whenever you are around gasoline, avoid in-
haling fumes and skin or clothing contact,
extinguish all smoking materials.
Direct skin contact with fuels and the inha-
lation of fuel vapors can be damaging to
your health.
!To maintain the engine’s durability and per-
formance, premium unleaded gasoline must be
used. If premium unleaded is not available and
low octane fuel is used, follow these precau-
tions:
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 acceler-
ation.
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.
Do not exceed 2/3 of maximum accelerator
pedal position if the vehicle is fully loaded or
operating in mountainous terrain.
Page 453 of 481

452 Technical data
Fuels, coolants, lubricants, etc.
Gasoline additives
A major concern among engine manufac-
turers is carbon build-up caused by gaso-
line. Mercedes-Benz recommends only the
use of quality gasoline containing additives
that prevent the build-up of carbon depos-
its.
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 en-
gine performance problems such as:
Warm-up hesitation
Unstable idle
Knocking/pinging
Misfire
Power lossIn areas where carbon deposits may be en-
countered due to lack of availability of gas-
olines which contain these additives,
Mercedes-Benz recommends the use of
additives approved by us for use on
Mercedes-Benz vehicles. Refer to Factory
Approved Service Products pamphlet for a
listing of approved product(s). Follow di-
rections on 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 addition-
al fuel additives other than those tested
and approved by us for use on
Mercedes-Benz vehicles listed in the
Factory Approved Service Products pam-
phlet are not covered by the
Mercedes-Benz Limited Warranty.
Page 454 of 481

453 Technical data
Fuels, coolants, lubricants, etc.
Coolants
The engine coolant is a mixture of water
and anticorrosion / antifreeze, which
provides:
Corrosion protection
Freeze protection
Boiling protection (by increasing the
boiling point)
The cooling system was filled at the factory
with a coolant providing freeze protection
to approximately -22°F (-30°C) and corro-
sion protection.
If the antifreeze mixture is effective
to -22°F (-30°C), the boiling point of the
coolant in the pressurized cooling system
is reached at approx. 266°F (130°C).The coolant solution must be used
year-round to provide the necessary corro-
sion protection and increase boil-over pro-
tection. Refer to 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 solu-
tion or other Mercedes-Benz approved
products of equal specification (see Facto-
ry Approved Service Products pamphlet)
are used to renew the coolant concentra-
tion or bring it back up to the proper level.To provide important corrosion protection,
the solution must be at least 45% anticor-
rosion/antifreeze (equivalent to freeze
protection to approx. -22°F [-30°C]). If you
use a solution that is more than 55% anti-
corrosion/antifreeze (freeze protection to
approx. -49°F [-45°C]), the engine temper-
ature will increase due to the lower heat
transfer capability of the solution. There-
fore, do not use more than this amount of
anticorrosion/antifreeze.
If the coolant level is low, water and MB
Anticorrosion /Antifreeze should be used
to bring it up to the proper level (have cool-
ing system checked for signs of leakage).
Please make sure the mixture is in accor-
dance 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,
consult an authorized Mercedes-Benz
Center.
!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
Page 455 of 481

454 Technical data
Fuels, coolants, lubricants, etc.
Anticorrosion/antifreeze
Your vehicle contains a number of alumi-
num parts. The use of aluminum compo-
nents in motor vehicle engines
necessitates that anticorrosion/antifreeze
coolant used in such engines be specifical-
ly formulated to protect the aluminum parts. (Failure to use such anticorro-
sion/antifreeze coolant will result in a sig-
nificantly shortened service life.)
Therefore, the following product is strongly
recommended for use in your vehicle:
Mercedes-Benz 325.0 Anticorrosion/Anti-
freeze 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.
Anticorrosion/antifreeze quantity
ModelApprox. freeze protection
–35°F (–37°C)–49°F (–45°C)
CLK 3503.9 US qt (3.7 l)4.3 US qt (4.1 l)
CLK 5504.9 US qt (4.6 l)5.3 US qt (5.1 l)
Page 456 of 481

455 Technical data
Fuels, coolants, lubricants, etc.
Windshield washer system and
headlamp cleaning system*
Both the windshield washer and headlamp
cleaning system are supplied from the
windshield washer fluid reservoir.
The washer fluid reservoir has a capacity of
approx. 6.4 US qt (6.0 l).
Refill the reservoir with MB Windshield
Washer Concentrate “MB SummerFit”
and water (or concentrate and com-
mercially available premixed wind-
shield washer solvent / antifreeze,
depending on ambient temperatures).Windshield and headlamp washer fluid
mixing ratio
For temperatures above freezing point, use
MB Windshield Washer Concentrate
“MB SummerFit” and water:
1 part “MB SummerFit” to 100 parts
water
(1.34 fl oz [40 ml] “MB SummerFit” to
1 gallon [4.0 l] water)
For temperatures below freezing point, use
MB Windshield Washer Concentrate
“MB SummerFit” and commercially avail-
able premixed windshield washer
solvent / antifreeze:
1 part “MB SummerFit” to 100 parts
solvent
(1.34 fl oz [40 ml] “MB SummerFit” to
1 gallon [4.0 l] solvent)
Warning!G
Washer solvent/antifreeze is highly flam-
mable. Do not spill washer
solvent/antifreeze on hot engine parts, be-
cause it may ignite and burn. You could be
seriously burned.