2005 MERCEDES-BENZ SLK CLASS Owners Manual

425 Technical data
Fuels, coolants, lubricants, etc.
Premium unleaded gasoline
Fuel 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.
Gasoline additives
A major concern among engine manufac-
turers is carbon build-up caused by gaso-
line. Mercedes-Benz only recommends 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
engine performance problems such as:

Warm-up hesitation


Unstable idle


Knocking/pinging


Misfire


Power loss
!To maintain the engine’s durability and
performance, premium unleaded gaso-
line must be used. If premium unleaded
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
2/3of maximum ac-
celerator pedal position if the vehi-
cle is fully loaded or operating in
mountainous terrain.

426 Technical dataFuels, coolants, lubricants, etc.In areas where carbon deposits may be
encountered due to lack of availability of
gasolines which contain these additives,
Mercedes-Benz recommends the use of
additives approved by us for use on
Mercedes-Benz vehicles. Refer to the
Factory Approved Service Products pam-
phlet for a listing of approved product(s).
Follow directions on product label.
Do not blend any specific fuel additives
with fuel. This only results in unnecessary
costs and may be harmful to engine opera-
tion.
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
pamphlet are not covered by the
Mercedes-Benz Limited Warranty.
Coolants
The engine coolant is a mixture of water
and anticorrosion/antifreeze, which pro-
vides:

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 cool-
ant 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 Maintenance Booklet for in-
formation on replacement intervals.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
Factory Approved Service Products
pamphlet) are used to renew the coolant
concentration 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.

427 Technical data
Fuels, coolants, lubricants, etc.
If the coolant level is low, water and
MB Anticorrosion/Antifreeze should be
used to bring it up to the proper level (have
cooling system checked for signs of leak-
age). Please make sure 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 you
are not sure about the water quality, con-
sult an authorized Mercedes-Benz Center.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
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 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.

428 Technical dataFuels, coolants, lubricants, etc.Anticorrosion/antifreeze quantityModel
Approx. freeze protection–35°F (–37°C)
–49°F (–45°C)
SLK 350
5.4 US qt (5.1 l)
6.0 US qt (5.6 l)
SLK 55 AMG
5.9 US qt (5.5 l)
6.4 US qt (6.1 l)

429 Technical data
Fuels, coolants, lubricants, etc.
Windshield washer system and head-lamp cleaning system*
Both the windshield washer system and
the headlamp cleaning system* are sup-
plied from the windshield washer fluid res-
ervoir.
The washer fluid reservoir has a capacity of
approximately 7.4 US qt (7.0 l).
Refill the reservoir with MB Windshield
Washer Concentrate “S” and water (or
concentrate and commercially avail-
able premixed windshield washer sol-
vent/antifreeze, depending on ambient
temperatures).Windshield washer and headlamp
cleaning* fluid mixing ratio
For temperatures above freezing point, use
MB Windshield Washer Concentrate “S”
and water:


1 part “S” to100 parts water
[40 ml (1.34 fl oz) “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:


1part“S” to 100parts solvent
[40 ml (1.34 fl oz) “S” to 1 gallon (4 l)
solvent].
Warning!
G
Washer solvent/antifreeze is highly flamma-
ble. Do not spill washer solvent/antifreeze
on hot engine parts because it may ignite
and burn. You could be seriously burned.

430

431 Technical terms
ABS
(A
ntilock B
rake S
ystem)
Prevents the wheels from locking up
during braking so that the vehicle can
continue to be steered.
Accessory weight
(
page 323)
Air pressure
(page 323)
AIRSCARF neck-level heating
AIRSCARF neck-level heating provides
the surrounding area of the occupants’
necks with a heated air stream flowing
from openings in the head restraints.
Alignment bolt
Metal pin with thread. The centering
pin is an aid used when changing a tire
to align the wheel with the wheel hub.
Aspect ratio
(page 323)BabySmart
TM1
air bag deactivation
system
This system detects if a special
system-compatible child restraint seat
is installed on the passenger seat.
The system will automatically
deactivate the passenger front air bag
when such a seat is properly installed
(the 75indicator lamp
located in the center console comes
on).
BabySmart
TM
compatible child seats
Special restraint system for children.
The sensor system for the passenger
seat prevents deployment of the pas-
senger front air bag if a BabySmart
TM
compatible child seat is installed. See
an authorized Mercedes-Benz Center
for availability.
Bar
(
page 323)BAS
(B
rake A
ssist S
ystem)
System for potentially reducing braking
distances in emergency braking situa-
tions. The system is activated when it
senses an emergency based on how
fast the brake is applied.
Bead
(
page 323)
Bi-Xenon headlamps
Headlamps which use an electric arc as
the light source and produce a more in-
tense light than filament headlamps.
Bi-Xenon headlamps produce low
beam and high beam.
CAC
(Customer A
ssistance C
enter)
Mercedes-Benz customer service cen-
ter, which can help you with any ques-
tions about your vehicle and provide
assistance in the event of a break-
down.
1BabySmart
TM
is a trademark of Siemens
Automotive Corp.

432 Technical termsCAN system
(C
ontroller A
rea N
etwork)
Data bus network serving to control ve-
hicle functions such as door locking or
windshield wiping.
Cockpit
All instruments, switches, buttons and
indicator/warning lamps in the passen-
ger compartment needed for vehicle
operation and monitoring.
Cold tire inflation pressure
(
page 323)
Collapsible tire
An especially compact spare tire that
must be inflated with a provided air
pump before using. It should only be
used to bring the vehicle to the nearest
service station.COMAND
(Co
ckpit Man
agement and
D
ata System)
Information and operating center for
vehicle sound and communications
systems, including the radio,
CD changer and navigation system, as
well as other optional equipment (e.g.
telephone).
Control system
The control system is used to call up
vehicle information and to change
component settings. Information and
messages appear in the multifunction
display. The driver uses the buttons on
the multifunction steering wheel to
navigate through the system and to ad-
just settings.
Cruise control
Driving convenience system for auto-
matically maintaining the vehicle speed
set by the driver.Curb weight
(
page 323)
DOT
(Department o
f Transportation)
(
page 323)
Engine number
The number set by the manufacturer
and placed on the cylinder block to
uniquely identify each engine pro-
duced.
Engine oil viscosity
Measurement for the inner friction (vis-
cosity) of the oil at different tempera-
tures. The higher the temperature an
oil can tolerate without becoming thin,
or the lower the temperature it can tol-
erate without becoming viscous, the
better the viscosity.
ESP
(Electronic S
tability Pr
ogram)
Improves vehicle handling and direc-
tional stability.