412 Technical dataFuels, coolants, lubricants, etc.Engine oils
Engine oils are specifically tested for their
suitability in our engines. Therefore, only
use engine oils approved by
Mercedes-Benz. Information on approved
engine oils is available in the Factory Ap-
proved Service Products pamphlet, or at
your authorized Mercedes-Benz Center.Please follow FSS 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 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 condition-
ing system.Never use R-12 (CFC) or mineral-based lu-
bricating 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 strenu-
ous operating conditions, this moisture
content can lead to the formation of bub-
bles in the system, thus reducing the sys-
tem’s efficiency.
Therefore, the brake fluid must be re-
placed every two years, preferably in the
spring.
Only brake fluid approved by
Mercedes-Benz is recommended. Your au-
thorized Mercedes-Benz Center will pro-
vide you with additional information.
!Always check the oil filler cap
(page 291) for important information
pertaining to the engine oil needing to
meet a specific Mercedes-Benz specifi-
cation (e.g. MB 229.5). If such informa-
tion is printed on the oil filler cap, only
use an engine oil from the list of ap-
proved engine oils in the Factory Ap-
proved Service Products pamphlet that
meets the specification indicated on
the oil filler cap.
Using engine oils of other specification
may cause the FSS to incorrectly deter-
mine the next service interval and will
result in engine damage not covered by
the Mercedes-Benz Limited Warranty.
413 Technical data
Fuels, coolants, lubricants, etc.
Premium unleaded gasoline
Fuel requirements
Only use premium unleaded gasoline
meeting ASTM standard D 439:
The octane number (posted at the
p um p) m us t be 91 mi n. It i s an a vera ge
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.
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 loss
Do not blend any specific fuel additives
with fuel. This only results in unnecessary
cost and may be harmful to the engine op-
eration.
!To maintain the engine’s durability and
performance, premium unleaded gaso-
l i n e m u s t b e u s e d . I f p r e m i u m u n l e a d e d
is not available and low octane fuel is
used, follow these precautions:
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
acceleration.
Do not exceed an engine speed of
3 000 rpm if the vehicle is loaded
with a light load such as two per-
sons and no luggage.
Do not exceed
2⁄3 of maximum ac-
celerator pedal position if the vehi-
cle is fully loaded or operating in
mountainous terrain.
414 Technical dataFuels, coolants, lubricants, etc.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 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 approximately 266°F
(130°C).
The coolant solution must be used year
round to provide the necessary corrosion
protection and increase boil-over protec-
tion. Refer to Service Booklet for replace-
ment interval.
Coolant system design and coolant used
stipulate the replacement interval. The
replacement interval published in the
Service 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, con-
sult your authorized Mercedes-Benz
Center.
415 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 Mercedes-Benz 325.0 An-
ticorrosion/Antifreeze AgentBefore 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 your authorized Mercedes-Benz
Center for service.
Anticorrosion/antifreeze quantityModel
Approx. freeze protection–35°F (–37°C)
–49°F (–45°C)
CLK 320
5.3 US qt (5.0 l)
5.9 US qt (5.5 l)
CLK 500
6.4 US qt (6.0 l)
7.0 US qt (6.6 l)
CLK 55 AMG
6.4 US qt (6.0 l)
7.0 US qt (6.6 l)
416 Technical dataFuels, 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 “S” and water (or
concentrate and commercially avail-
able premixed windshield washer
solvent / antifreeze, depending on am-
bient temperatures).Windshield and headlamp washer fluid
mixing ratio
For temperatures above freezing point, use
MB Windshield Washer Concentrate “S”
and water:
1 part “S” to 100 parts water
[40 ml “S” to 1 gallon (4 l) water].
For temperatures below freezing point, use
MB Windshield Washer Concentrate “S”
and commercially available premixed
windshield washer solvent / antifreeze:
1 part “S” to 100 parts solvent
[40 ml “S” to 1 gallon (4 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.
424 Technical termsRemote Vehicle Diagnostics
Transmission of vehicle data and cur-
rent location to the Mercedes-Benz
Customer Assistance Center for sub-
scribers to Tele Aid service.
REST
(Residual engine heat utilization)
Feature that uses the engine heat
stored in the coolant to heat the vehi-
cle interior for a short time after the en-
gine has been turned off.
Restraint systems
Seat belts, belt tensioners, airbags and
child restraint systems. As indepen-
dent systems, their protective func-
tions complement one another.Roll bars
Occupant protection system which
consists of tubular steel, integrated in
the rear head restraints. The roll bars
are lowered into the car body during
normal driving conditions and raised
automatically in an accident or in a crit-
ical driving situation.
RON
(R
esearch O
ctane N
umber)
The Research Octane Number for gaso-
line as determined by a standardized
method. It is an indication of a gaso-
line's ability to resist undesired detona-
tion (knocking). The average of both
the ->MON (Motor Octane Number)
and RON (Research Octane Number) is
posted at the pump, also known as
ANTI-KNOCK INDEX.Shift lock
When the vehicle is parked, this lock
prevents the gear selector lever from
being inadvertently moved out of
positionP without SmartKey turned
and brake pedal depressed.
Soft top
Soft top roof that can be opened by
pulling and closed by pressing a switch
and stored in the soft top compartment
in the trunk area.
Speedshift (CLK 55 AMG)
Steering wheel gearshift control. You
can change the gears yourself with the
steering wheel gearshift buttons.
SRS
(S
upplemental R
estraint S
ystem)
Seat belts, emergency tensioning de-
vice and airbags. Though independent
systems, they are closely interfaced to
provide effective occupant protection.
427 Index
A
ABS 23, 77, 419
Malfunction indicator lamp 312
Messages in display 321
Accelerator position,
automatic transmission 163
Accident
In case of 51
Activating
Air conditioning (cooling) 181
Air recirculation mode 178
Anti-theft alarm system 83
Automatic climate control 173
Central locking (control system) 149
Charcoal filter 179
Distance warning function* 238
Distronic* 233, 234
Easy-entry/exit feature 150
ESP 81
Exterior headlamps 47
Exterior lamps 120
Exterior rear view
mirror parking position 169
Front and rear fog lamp 121, 122
Hazard warning flasher 123
Headlamps 47High beams 123
Ignition 31
Ignition with KEYLESS-GO* 33
Immobilizer 54, 82
Manual shift programm
CLK 55 AMG 164
Rear window defroster 171
Residual heat 181
Seat ventilation* 113
Steering wheel gearshift
control (CLK 55 AMG) 164
Tow-away alarm 85
Windshield wipers 49
Adding
Coolant 292
Engine oil 291
Additional turn signals 373
Adjustable air vents,
rear passenger compartment 182Adjusting 34
Air distribution 176
Air volume 177
Backrest tilt 36
Exterior rear view mirror 39
Head restraint height 36
Head restraint tilt 36
Instrument cluster illumination 126
Interior rear view mirror 38
Mirrors 38
Multicontour seat* 112
Seat cushion depth 112
Seat cushion tilt 36
Seat fore and aft adjustment 35
Seat height 36
Seats 34
Steering column in/out 38
Steering column up/down 38
Steering wheel 37
Air conditioning (cooling)
Turning off 181
Turning on 181
Air conditioning refrigerant 412
Air distribution
Adjusting 176
431 Index
Centigrade
Setting temperature units 142
Central locking
Automatic 107
From inside 108
Locking from inside 108
Switch 108
Switching on/off
(control system) 149
Unlocking from inside 108
Central locking switch 108
Changing
Batteries (SmartKey with
KEYLESS-GO*) 351
Batteries (SmartKey) 350
Key setting 149
Changing CDs 199
Charcoal filter 179
Activating 179
Deactivating 180
Charging
Vehicle battery 386
CHECK ENGINE
malfunction indicator lamp 314Checking
Coolant level 292
Oil level 286, 289
Tire inflate pressure 286
Vehicle lighting 286
Child safety 69
Airbags 60
Infant and child
restraint systems 64, 69
LATCH child seat anchors 73
Child safety switch see
Blocking of rear window operation
Child seat anchors see
LATCH child seat anchors
Cigarette lighter 254Cleaning
Cup holder 309
Distronic* system sensor cover 308
Gear selector lever 309
Hard plastic trim items 310
Headlamps 167
Headliner 310
Instrument cluster 309
Leather upholstery 310
Light alloy wheels 309
Nubuck leather upholstery
(CLK 55 AMG) 310
Parktronic* system sensor 308
Plastic and rubber parts 310
Seat belts 310
Soft top 306
Steering wheel 309
Upholstery 310
Windows 309
Windshield 50
Wiper blades 308
Wood trims 310
CLK 55 AMG
Manual shift program mode 164
Clock 23, 144