Page 407 of 464
407 Technical data
Electrical system
Electrical system
Model
CLK 320
CLK 500
CLK 55 AMG
Generator (alternator)
14 V/120 A
14 V/150 A
14 V/150 A
Starter motor
14 V/1.4 KW
14 V/1.7 KW
14 V/1.7 KW
Battery
12 V/100 Ah
12 V/100 Ah
12 V/100 Ah
Spark plugs
Bosch F8 DPP 332
NGK PFR 5R-11
Bosch F8 DPP 332
NGK PFR 5R-11
NGK ILFR 6A
Electrode gap
0.039 in (1.00 mm)
0.039 in (1.00 mm)
0.031 in (0.8 mm)
Tightening torque
18.5 - 22 lb-ft (25 - 30 Nm)
18.5 - 22 lb-ft (25 - 30 Nm)
18.5 - 22 lb-ft (25 - 30 Nm)
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408 Technical dataMain dimensions
Main dimensionsModel
CLK 320
CLK 500
CLK 55 AMG
Overall vehicle length
182.6 in (4 638 mm)
182.6 in (4 638 mm)
182.6 in (4 638 mm)
Overall vehicle width
68.5 in (1 740 mm)
68.5 in (1 740 mm)
68.5 in (1 740 mm)
Overall vehicle height
55.4 in (1 406 mm)
55.4 in (1 408 mm)
55.4 in (1 408 mm)
Overall vehicle height when
opening/closing soft top
80.9 in (2 055 mm)
81.0 in (2 057 mm)
80.6 in (2 047 mm)
Wheelbase
106.9 in (2 715 mm)
106.9 in (2 715 mm)
106.9 in (2 715 mm)
Track, front
58.8 in (1 493 mm)
58.9 in (1 497 mm)
58.9 in (1 497 mm)
Track, rear
58.0 in (1 474 mm)
58.2 in (1 478 mm)
58.2 in (1 478 mm)
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Page 409 of 464
409 Technical data
Weights
Weights
Trunk load max.
220 lb (100 kg)
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Page 410 of 464

410 Technical dataFuels, coolants, lubricants, etc.
Fuels, coolants, lubricants, etc.CapacitiesVehicle components and their respective
lubricants must match. Therefore only use
brands tested and approved by
Mercedes-Benz.Please refer to the Factory Approved Ser-
vice Products pamphlet, or inquire at your
Mercedes-Benz Center.
Model
Capacity
Fuels, coolants, lubricants, etc.
Engine with oil filter
CLK 320
CLK 500
CLK 55 AMG
8.5 US qt (8.0 l)
8.0 US qt (7.5 l)
9.0 US qt (8.5 l)
Approved engine oils
Automatic transmission
CLK 320
CLK 500
CLK 55 AMG
8.0 US qt (7.5 l)
9.3 US qt (8.7 l)
9.3 US qt (8.7 l)
MB Automatic Transmission Oil
Rear axle
CLK 320
CLK 500
CLK 55 AMG
1.28 US qt (1.2 l)
1.5 US qt (1.4 l)
1.5 US qt (1.4 l)
Hypoid gear oil SAE 85 W 90
Power steering
approx. 1.1 US qt (1.0 l)
MB Power Steering Fluid (Pentosin
CHF 11S)
Front wheel hubs
approx. 3.0 oz (85 g) each
High temperature roller bearing grease
Brake system
0.64 US qt (0.6 l)
MB Brake Fluid (DOT 4+)
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411 Technical data
Fuels, coolants, lubricants, etc.
Model
Capacity
Fuels, coolants, lubricants, etc.
Cooling system
CLK 320
CLK 500
CLK 55 AMG
approx. 10.7 US qt (10.0 l)
approx. 12.8 US qt (12.0 l)
approx. 12.8 US qt (12.0 l)
MB 325.0 Anticorrosion/Antifreeze
Agent
Fuel tank
including a reserve of
16.35 US gal (62.0 l)
2.11 US gal (8.0 l)
Premium unleaded gasoline:
Posted Octane 91 (Avg. of 96
RON / 86 MON)
Air conditioning system
R-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 Concentrate
1
1Use MB Windshield Washer Concentrate “S” and water for temperatures above freezing point or MB Windshield Washer Concentrate “S” and commercially available
premixed windshield washer solvent / antifreeze for temperatures below freezing point. Follow suggested mixing ratios (page 416).
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Page 412 of 464

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.
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Page 413 of 464

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.
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Page 414 of 464

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.
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