MERCEDES-BENZ SLK350 2005 R171 Owner's Manual

291 Operation
Engine compartment
Checking engine oil level with the oil
dipstick, SLK 350
When checking the oil level

the vehicle must be parked on level
ground.


with the engine at operating tempera-
ture, the vehicle must have been sta-
tionary for at least five minutes with
the engine turned off.


with the engine not at operating tem-
perature, the vehicle must have been
stationary for at least 30 minutes with
the engine turned off.1Oil dipstick
2Upper (max) mark
3Lower (min) mark
To check the engine oil level with the oil
dipstick, do the following:

Open the hood (
page 287).

Pull out oil dipstick1.

Wipe oil dipstick1 clean.

Fully insert oil dipstick1 into the
dipstick guide tube.

Pull out oil dipstick1 again after
approximately three seconds to obtain
accurate reading.
The oil level is correct when it is be-
tween the lower (min) mark3 and
upper (max) mark2 of oil dipstick1.

If necessary, add engine oil.
For adding engine oil, see “Adding en-
gine oil” (
page 292).
For more information on engine oil, see
“Fuels, coolants, lubricants, etc.”
(
page 422).
For more information on messages in the
multifunction display concerning engine
oil, see the “Practical hints” section
(page 348).iThe filling quantity between the upper
and lower marks on the oil dipstick is
approximately 2.1 US qt. (2.0 l).

292 OperationEngine compartmentAdding engine oil
Only use approved engine oils and oil fil-
ters required for vehicles with Mainte-
nance System (U.S. vehicles) or FSS
(Canada vehicles). For a listing of approved
engine oils and oil filters, refer to the Fac-
tory Approved Service Products pamphlet
in your vehicle literature portfolio, or con-
tact an authorized Mercedes-Benz Center.
Using engine oils and oil filters of specifica-
tion other than those expressly required
for the Maintenance System (U.S. vehi-
cles) or FSS (Canada vehicles), or changing
of oil and oil filter at change intervals long-
er than those called for by the Mainte-
nance System (U.S. vehicles) or FSS
(Canada vehicles) will result in engine dam-
age not covered by the Mercedes-Benz
Limited Warranty.
SLK 3501Filler capSLK 55 AMG1Filler cap

Unscrew filler cap1 from filler neck.

Add engine oil as required.
Be careful not to overfill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.

Screw filler cap1 back on filler neck.
For more information on engine oil, see the
“Technical data” section (
page 422) and
(
page 424).!Excess oil must be siphoned or drained
off. It could cause damage to the
engine and catalytic converter not
covered by the Mercedes-Benz Limited
Warranty.

293 Operation
Engine compartment
Transmission fluid level*
Vehicles with automatic transmission*:
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Center
check the transmission.
Coolant level
The engine coolant is a mixture of water
and anticorrosion/antifreeze. To check
the coolant level, the vehicle must be
parked on level ground and the engine
must be cool.Warning!
G
In order to avoid any possibly serious burns:

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 indi-
cates that the coolant is overheated.


Do not remove pressure cap on coolant
reservoir if coolant temperature is
above 158°F (70°C). Allow engine to
cool down before removing cap. The
coolant reservoir contains hot fluid and
is under pressure.


Using a rag, slowly open the cap approx-
imately ½ turn to relieve excess pres-
sure. If opened immediately, scalding
hot fluid and steam will be blown out un-
der 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.

294 OperationEngine compartmentThe coolant expansion tank is located on
the passenger side of the engine compart-
ment.SLK 350 (example)1Coolant expansion tank
2Cap
3Marking bar in the expansion tank

Using a rag, turn cap2 slowly approx-
imately one half turn counterclockwise
to release any excess pressure.

Continue turning cap2 counterclock-
wise and remove it.
The coolant level is correct if the level

for cold coolant: reaches marking
bar3 in expansion tank1


for warm coolant: is approximately
0.6 in (1.5 cm) higher

Add coolant as required.

Replace and tighten cap2.
For more information on coolant, see
“Coolants” (
page 426).
Battery
Your vehicle’s battery is located in the en-
gine compartment.
The battery should always be sufficiently
charged in order to achieve its rated ser-
vice life. Refer to the Maintenance Booklet
for battery maintenance intervals.
If you use your vehicle mostly for
short-distance trips, you will need to have
the battery charge checked more frequent-
ly.
When replacing the battery, always use
batteries approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, consult an
authorized Mercedes-Benz Center about
steps you need to observe.

295 Operation
Engine compartment
Batteries contain materials that can harm
the environment if disposed of improperly.
Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.Windshield washer system and
headlamp cleaning system*
The windshield washer reservoir is located
on the passenger side of the engine com-
partment.SLK 350 (example)1Washer fluid reservoir cap
Fluid for the windshield washer system and
the headlamp cleaning system* is supplied
from the windshield washer reservoir. It
has a capacity of approx. 7.4 US qt (7 l).
G
Observe all safety instructions
and precautions when handling
automotive batteries.
A
Risk of explosion
D
Keep flames or sparks away
from battery. Do not smoke.
B
Battery acid is caustic. Do not
allow it to come into contact
with skin, eyes or clothing.
In case it does, immediately
flush affected area with clean
water and seek medical help if
necessary.
E
Wear eye protection.
C
Keep children away.
F
Follow the instructions in this
Operator's Manual.

296 OperationEngine compartmentDuring all seasons, add MB Windshield
Washer Concentrate “S” to water. Premix
the windshield washer fluid in a suitable
container.
Pull cap upward using latch until it
opens.

Refill the reservoir with MB Windshield
Washer Concentrate and water (or
commercially available premixed wind-
shield washer solvent/antifreeze, de-
pending on ambient temperatures).
Always use washer solvent/antifreeze
where temperatures may fall below
freezing point. Failure to do so could re-
sult in damage to the washer sys-
tem/reservoir.

Push cap down until it engages.For more information, see “Windshield
washer system and headlamp cleaning
system*” (
page 429).
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.!Only use washer fluid which is suitable
for plastic lenses. Improper washer flu-
id can damage the plastic lenses of the
headlamps.

297 Operation
Tires and wheels
Tires and wheels
See an authorized Mercedes-Benz Center
for information on tested and recommend-
ed rims and tires for summer and winter
operation. They can also offer advice con-
cerning tire service and purchase.
Retreaded tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on
retreads. Mercedes-Benz therefore cannot
assure the operating safety of the vehicle
when such tires are used.
Important guidelines

Only use sets of tires and rims of the
same type and make.


Tires must be of the correct size for the
rim.


Break in new tires for approximately
60 miles (100 km) at moderate
speeds.


Regularly check the tires and rims for
damage. Dented or bent rims can
cause tire inflation pressure loss or
damage the tire beads.


If vehicle is heavily loaded, check tire
inflation pressure and correct as re-
quired.


Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths under
1/8in (3 mm).


When replacing individual tires, you
should mount new tires on the front
wheels first (on vehicles with
same-sized wheels all around).
Warning!
G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. See an authorized
Mercedes-Benz Center for further informa-
tion. If incorrectly sized rims and tires are
mounted:

The wheel brakes or suspension compo-
nents can be damaged.


The operating clearance of the wheels
and the tires may no longer be correct.
Warning!
G
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can re-
sult in the bolts loosening and may lead to
an accident.

298 OperationTires and wheelsTire care and maintenance
Regularly check your tire inflation pressure
at least once a month. For more informa-
tion on checking tire inflation pressure,
see “Recommended tire inflation pres-
sure” (
page 306).Tire inspection
Every time you check your tire inflation
pressure, you should also inspect your
tires for the following:


excessive treadwear (
page 299)


cord or fabric showing through the
tire’s rubber


bumps, bulges, cuts, cracks or splits in
the tread or side of the tire
Replace the tire if you find any of the above
conditions.
Make sure you also inspect the spare tire
periodically for condition and inflation.
Spare tires will age and become worn over
time even if never used, and thus should be
inspected and replaced when necessary.Life of tire
The service life of a tire is dependent upon
varying factors including but not limited to:


Driving style


Tire inflation pressure


Distance driven
Warning!
G
Regularly check the tires for damage. Dam-
aged tires can cause tire inflation pressure
loss. As a result, you could lose control of
your vehicle.
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
Warning!
G
Tires and spare tire should be replaced after
six years, regardless of the remaining tread.

299 Operation
Tires and wheels
Tread depth
Do not allow your tires to wear down too
far. Adhesion properties on wet roads are
sharply reduced at tread depths under 1⁄8in (3 mm).
Treadwear indicators (TWI) are required by
law. These indicators are located in six
places on the tread circumference and
become visible at a tread depth of approx-
imately
1/16
in (1.6 mm), at which point
the tire is considered worn and should be
replaced.
Recommended minimum tire tread depth:


Summer tires
1/8in (3 mm)


Winter tires
1/6in (4 mm)
1TWI (T
read W
ear I
ndicator)
The treadwear indicator appears as a solid
band across the tread.Storing tires
Cleaning tires
Warning!
G
Although the applicable federal motor safety
laws consider a tire to be worn when the
treadwear indicators (TWI) become visible at
approximately
1/16in (1.6 mm), we recom-
mend that you do not allow your tires
to wear down to that level. As tread depth
approaches
1/8in (3 mm), the adhesion
properties on a wet road are sharply re-
duced.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
!Keep unmounted tires in a cool, dry
place with as little exposure to light as
possible. Protect tires from contact
with oil, grease and gasoline.!Never use a round nozzle to power
wash tires. The intense jet of water can
result in damage to the tire.
Always replace a damaged tire.

300 OperationTires and wheelsDirection of rotation
Unidirectional tires offer added advan-
tages, such as better hydroplaning perfor-
mance. To benefit, however, you must
make sure the tires rotate in the direction
specified.
An arrow on the sidewall indicates the
intended direction of rotation (spinning) of
the tire.
Loading the vehicle
Two labels on your vehicle show how much
weight it may properly carry.

The Tire and Loading Information
placard (Example A) or the Vehicle Tire
Information placard (Example B) can be
found on the driver’s door B-pillar. This
placard tells you important information
about the number of people that can be
in the vehicle and the total weight that
can be carried in the vehicle. It also
contains information on the proper size
and recommended tire inflation
pressures for the original equipment
tires on your vehicle.


The Certification label, also found on
the driver’s door B-pillar tells you about
the gross weight capacity of your vehi-
cle, called the Gross Vehicle Weight
Rating (GVWR). The GVWR includes the
weight of the vehicle, all occupants,
fuel and cargo. The Certification label
also tells you about the front and rear
axle weight capacity, called the Gross
Axle Weight Rating (GAWR). The GAWR
is the total allowable weight that can be
carried by a single axle (front or rear).
Never exceed the GVWR or GAWR for
either the front axle or rear axle.
iSpare wheels may be mounted against
the direction of rotation (spinning) even
with a unidirectional tire for temporary
use only until the regular drive wheel
has been repaired or replaced. Always
observe and follow applicable tempo-
rary use restrictions and speed limita-
tions indicated on the spare wheel.