254 Engine compartment
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
Adding coolant
If coolant has to be added, a 50 / 50 mixture of water and
MB anticorrosion / antifreeze should be added.
The drain plugs for the cooling system are located on
the right side of the engine block and at the bottom of
the radiator.
Anticorrosion / antifreeze mixture, see page 321.
Wa r n i n g !
In order to avoid possible serious burns or injury:
• 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 indicates that the coolant is
overheated.• Do not remove pressure cap on coolant
reservoir if engine temperature is above 194
°F
(90
°C). Allow engine to cool down before
removing cap. The coolant reservoir contains
hot fluid and is under pressure.
• Using a rag, slowly open cap approximately
1/2 turn to relieve excess pressure. 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.
ProCarManuals.com
307
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
Technical dataSpare parts service ........................308
Warranty coverage .........................308
Identification labels .......................309
Layout of poly-V-belt drive ............ 310
Technical data ................................ 311
Fuels, coolants, lubricants etc. –
capacities ................................... 316
Engine oils ...................................... 318Engine oil additives ....................... 318
Air conditioner refrigerant ........... 318
Brake fluid ....................................... 318
Premium unleaded gasoline ......... 319
Fuel requirements ......................... 319
Gasoline additives ......................... 320
Coolants .......................................... 320
Consumer information ................. 322
ProCarManuals.com
310 Technical data
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
CLK 320 shown
3VIN, visible (lower edge of windshield)
4Engine number
5Body number and paintwork number
6Emission control label
7Information label, California version
Vacuum line routing for emission control systemLayout of poly-V-belt drive
1Automatic belt tensioner
2Crankshaft
3Air conditioner compressor
4Coolant pump
5Generator (alternator)
6Idler pulley
7Power steering pump
ProCarManuals.com
316 Fuels, coolants, lubricants etc. - capacities
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
Fuels, coolants, lubricants etc. – capacities
Vehicle components and their respective lubricants must match. Therefore use only brands tested and recommended
by us. Please refer to the Factory Approved Service Products pamphlet, or inquire at your Mercedes-Benz Center.
Fuels, coolants, lubricants etc. Model Capacity
Engine with oil filter
(recommended engine oils)CLK 320, CLK 430 8.5 US qt (8.0 l)
Automatic transmission
(automatic transmission fluid)
1
CLK 320
CLK 4308.5 US qt (8.0 l)
9.6 US qt (9.1 l)
Rear axle
(Hypoid gear oil SAE 90, 85 W 90)1.4 US qt (1.3 l)
Power steering
(MB Power steering fluid)approx. 1.1 US qt (1.0 l)
Front wheel hubs
(high temperature roller bearing grease)approx. 2.1 oz (60 g) each
Brake system
(MB Brake fluid (DOT 4))approx. 0.5 US qt (0.5 l)
Cooling system
(MB 325.0 Anticorrosion/Antifreeze Agent)CLK 320
CLK 430approx. 9.5 US qt (9.0 l)
approx. 11.7 US qt (11.1 l)
1 MB part no. 001 989 21 03 10.
ProCarManuals.com
318 Fuels, coolants, lubricants etc.
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
Engine oils
Engine oils are specifically tested for their suitability in
our engines. Therefore, use only engine oils
recommended by Mercedes-Benz. Information on
recommended brands is available in the Factory
Approved Service Products pamphlet or at your
authorized Mercedes-Benz Center.
Please follow Service Booklet recommendations for
scheduled oil changes. Failure to do so could result in
engine damage not covered by the Mercedes-Benz
Limited Warranty.
Engine oil additives
Do not blend oil additives with engine oil. They may be
harmful to the engine operation.
Damage or malfunctions resulting from blending oil
additives are not covered by the Mercedes-Benz Limited
Warranty.Air conditioner refrigerant
R-134a (HFC) refrigerant and special PAG lubricating oil
is used in the air conditioner 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. Under extremely hard
operating conditions, this moisture content can lead to
the formation of bubbles in the system thus reducing
the system’s efficiency.
The brake fluid must therefore be replaced every two
years, preferably in the spring.
It is recommended to use only brake fluid approved by
Mercedes-Benz. Your authorized Mercedes-Benz Center
will provide you with additional information.
ProCarManuals.com
319 Fuels, coolants, lubricants etc.
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index Premium unleaded gasoline
Caution!
To maintain the engine’s durability and performance,
premium unleaded gasoline must be used. If premium
unleaded is not available and low octane fuel is used,
follow these precautions:
•Have the fuel tank filled only partially 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 3000 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.Fuel requirements
Use only Premium unleaded meeting ASTM
standard D 439:
The octane number (posted at the pump) must be
91 min. It is an average of both the Research (R) octane
number and the Motor (M) octane number: [(R+M)/2].
This is also known as 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..
ProCarManuals.com
320 Fuels, coolants, lubricants etc.
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
Gasoline additives
A major concern among engine manufacturers is carbon
build up caused by gasoline. Mercedes-Benz
recommends the use of only 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:
•Warm-up hesitation
•Unstable idle
•Knocking/pinging
•Misfire
•Power loss
Do not blend other specific fuel additives with fuel.
They only result in unnecessary cost, and may be
harmful to the engine operation.
Damage or malfunctions resulting from poor fuel
quality or from blending specific fuel additives are not
covered by the Mercedes-Benz Limited Warranty.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 corrosion 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 approximately 266
°F (130
°C).
The coolant solution must be used year-round to provide
the necessary corrosion protection and increase boil-
over protection. You should have it replaced every 15
years or 150 000 miles (250 000 km), whichever comes
first. Coolant system design and coolant used stipulate
the replacement interval. The above replacement
interval is only applicable if MB 325.0 anticorrosion/
antifreeze solution or other Mercedes-Benz approved
products of equal specification (see Factory Approved
Service Products pamphlet) are used to renew the
coolant concentration or bring it back up to the proper
level.
ProCarManuals.com
321 Fuels, coolants, lubricants etc.
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index To provide the important corrosion protection, the
solution must be at least 45% anticorrosion/antifreeze
(equals a freeze protection to approx. - 22
°F [-30
°C]). If
you use a solution that is more than 55% anticorrosion/
antifreeze (freeze protection to approx. - 49
°F [-45
°C]),
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 that 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 your are not sure about the water
quality, consult your 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: Mercedes-Benz
325.0 Anticorrosion/Antifreeze Agent.
Before the start of the winter season (or once a year in
the hot southern regions), you should have the
anticorrosion/antifreeze concentration checked. The
coolant is also regularly checked each time you bring
your vehicle to your authorized Mercedes-Benz Center
for service.
Anticorrosion/antifreeze quantity
Model Approx. freeze protection
-35
°F
(-37°C)-49
°F (
-45°C)
CLK 320 4.8 US qt
(4.5 l)5.3 US qt
(5.0 l)
CLK 430 5.9 US qt 6.5 US qt
ProCarManuals.com