engine coolant MERCEDES-BENZ CLK320 CABRIOLET 2003 C208 Owner's Guide

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.

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..

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.

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

326 Index
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car careIndex
CCapacities
Fuels, coolants, lubricants etc. ............................... 316
Cargo tie-down rings ..................................................... 152
Catalytic converter......................................................... 176
CD changer
See Audio system ...................................................... 136
Cellular telephone ......................................................... 153
Center console .................................................................. 18
Central locking switch .................................................... 33
Central locking system ................................................... 25
Automatic central locking ......................................... 34
Choosing global or selective mode........................... 28
Electronic key .............................................................. 23
Locking and unlocking............................................... 27
Mechanical keys ........................................................... 30
Remote control ............................................................ 25
Changing wheels ........................................................... 263
CHECK ENGINE malfunction indicator lamp............ 224
Check regularly and before a long trip ...................... 222
Checking engine oil level
Via engine oil level indicator .................................. 108
Via oil dipstick........................................................... 252Child restraint .............................................. 53, 58, 59, 69
Child seat
See Infant and child restraint systems .................... 69
Cleaning and care of the vehicle ................................ 300
Clock, setting .................................................................. 102
COMAND, radio and telephone.................................... 174
Combination switch ....................................................... 113
Consumer information ................................................. 322
Control and operation of radio transmitters .............. 174
COOLANT (coolant level) - malfunction and warning
messages ................................................................... 236
Coolant level
Adding coolant.......................................................... 254
Checking .................................................................... 253
COOLANT TEMP. (coolant temperature) - malfunction
and warning messages ............................................ 237
Coolant temperature gauge ............................................ 82
Coolants .......................................................................... 320
Anticorrosion/antifreeze quantity ........................ 320
Cruise control ................................................................. 210
Cup holder
Center console, front ................................................ 149

330 Index
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car careIndex
LLamps, exterior
Fog lamps ....................................................................110
Headlamp, adjusting ................................................282
Headlamps ..................... 110, 238, 239, 278, 282, 303
Low and high beam .......................................... 113, 279
Parking lamps ...................................................110, 279
Replacing bulbs ......................................................... 277
Side marker lamp, front ........................................... 281
Standing lamps ..................................................110, 279
Taillamp assemblies ......................................... 110, 280
Turn signal lamps ............................................. 113, 279
Layout of poly-V-belt drive ............................................ 310
LIGHT SENSOR - malfunction and
warning messages ......................................................... 239
Lighter ............................................................................. 151
LIGHTING SYSTEM - malfunction and
warning messages ......................................................... 238
Limp home mode (Automatic transmission) ............. 199
Locking and unlocking ................................................... 27
Low beams
See Exterior lamps .................................................... 277
Low engine coolant level warning............................... 236
Luggage cover .................................................................246
MMaintenance ................................................................... 175
Malfunction and indicator lamps in the
instrument cluster ....................................................... 224
Malfunction and warning messages .......................... 230
ABS-SYSTEM ............................................................. 233
BATTERY/ALTERNATOR ......................................... 232
BRAKE ASSIST ......................................................... 233
BRAKE FLUID ........................................................... 234
BRAKE LINING WEAR ............................................ 234
COOLANT (coolant level) ........................................ 236
COOLANT TEMP. (coolant temperature) .............. 237
DISPLAY DEFECTIVE (engine control unit) .........231
DISPLAY DEFECTIVE (several systems) ................231
ELEC. STABIL. PROG. ............................................... 241
ENGINE FAN ............................................................. 235
ENGINE OIL LEVEL ................................................. 240
LIGHT SENSOR ......................................................... 239
LIGHTING SYSTEM .................................................. 238
PARKING BRAKE ..................................................... 235
REMOVE KEY ............................................................ 241
STEER. WHEEL ADJUST. ......................................... 239
TELE AID ................................................................... 243
WASHER FLUID ........................................................ 242
Malfunction/warning message memory .................... 100