fuel cap MERCEDES-BENZ S550 4MATIC 2008 W221 Owner's Manual

Contents
Where will I find ...? ........................... 668
First aid kit ................................... 668
Vehicle jack, vehicle tool kit,
luggage bowl, Minispare wheel .... 668
Unlocking/locking in an emergency .. 671
Unlocking the vehicle ................... 671
Locking the vehicle ...................... 672
Mechanically releasing the
electronic parking brake .............. 673
Opening/closing in an emergency..... 674
Power tilt/sliding sunroof or
panorama roof with
power tilt/sliding panel*.............. 674
Resetting activated head restraints ... 675
Replacing SmartKey batteries ........... 676
Replacing bulbs ................................. 678
Bulbs ............................................ 679
Replacing bulbs for front lamps ... 680
Replacing wiper blades ...................... 684
Placing wiper arms in vertical
position ........................................ 684
Removing wiper blades ................ 685
Installing wiper blades................. 685
Flat tire .............................................. 686
Preparing the vehicle ................... 686
Mounting the spare wheel............ 686Batteries ............................................. 692
Disconnecting starter battery ....... 694
Removing starter battery .............. 695
Charging battery ........................... 695
Reinstalling starter battery ........... 696
Reconnecting starter battery ........ 696
Jump starting ...................................... 697
Towing the vehicle .............................. 700
Installing towing eye bolt .............. 703
Fuses .................................................. 704
Fuse boxes in engine
compartment ................................ 705
Fuse boxes in passenger
compartment ................................ 706
Emergency engine shut-down ....... 707
Technical data.................................. 709
Parts service....................................... 710
Warranty coverage ............................. 711
Loss of Service and Warranty
Information Booklet ...................... 711
Identification labels ............................ 712
Layout of poly-V-belt drive .................. 714
S 550 ............................................ 714
S 63 AMG ..................................... 714S 600 and S 65 AMG .................... 714
Engine ................................................ 715
Rims and tires .................................... 718
Same size tires ............................. 719
Mixed size tires ............................. 720
Spare wheel .................................. 721
Electrical system ................................ 722
Main dimensions and weights ............ 723
Main dimensions........................... 723
Weights......................................... 723
Fuels, coolants, lubricants, etc. .......... 724
Capacities ..................................... 724
Engine oils .................................... 728
Engine oil additives ....................... 728
Air conditioning refrigerant ........... 728
Brake fluid .................................... 728
Premium unleaded gasoline.......... 729
Fuel requirements......................... 729
Gasoline additives......................... 730
Coolants ....................................... 730
Windshield washer system and
headlamp cleaning system ........... 733
Index................................................. 735

538 Operation
At the gas station
RefuelingThe fuel filler flap is located on the
right-hand side of the vehicle towards the
rear. Locking and unlocking the vehicle
with the SmartKey or the SmartKey with
KEYLESS-GO* automatically locks and un-
locks the fuel filler flap.
1To open fuel filler flap
2To insert fuel filler cap
3HolderShift the automatic transmission to
park positionP.
Engage the electronic parking brake.
Turn off the engine.
Vehicles with SmartKey: Remove the
SmartKey from the starter switch.
Vehicles with KEYLESS-GO*: Open the
driver’s door (this puts the starter
switch in position0, same as with the
SmartKey removed from the starter
switch). The driver’s door then can be
closed again.
Open the fuel filler flap by pushing at
the point indicated by arrow 1.
The fuel filler flap springs open.
Turn the fuel cap counterclockwise and
hold on to it until possible pressure is
released.
Warning!G
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious per-
sonal injury.
Never allow sparks, flame or smoking mate-
rials near gasoline!
Turn off the engine before refueling.
Whenever you are around gasoline, avoid in-
haling fumes and skin or clothing contact,
extinguish all smoking materials.
Direct skin contact with fuels and the inha-
lation of fuel vapors are damaging to your
health.
iIn case that the central locking system does
not release the fuel filler flap, or the opening
mechanism is clamping, notify Roadside Assis-
tance or an authorized Mercedes-Benz Center.

539 Operation
At the gas station
Take off the fuel filler cap and set it in
the direction of arrow 2 and place it
into holder 3 located on the inside of
the fuel filler flap.
To prevent fuel vapors from escaping
into open air, fully insert filler nozzle
unit.
Only fill your tank until the filler nozzle
unit cuts out – do not top off or over-
fill.
Replace the fuel cap by turning it clock-
wise until it audibly engages.
Close the fuel filler flap.
You should hear the latch close shut.
Warning!G
Overfilling of the fuel tank may create pres-
sure in the system which could cause a gas
discharge. This could cause the gas to spray
back out when removing the fuel pump noz-
zle, which could cause personal injury.
iMake sure to close the fuel filler flap before
locking your vehicle as the flap locking pin pre-
vents closing after you have locked the vehicle.
iOnly use premium unleaded gasoline with a
minimum Posted Octane Rating of 91 (average of
96 RON/86 MON). Please contact gas station
personnel in case labels on the pump cannot be
found.
For more information on gasoline see “Premium
unleaded gasoline” (
page 729), see “Fuel re-
quirements” (
page 729) and the Factory Ap-
proved Service Products pamphlet.
iLeaving the engine running and the fuel cap
open can cause the yellow engine malfunction
indicator lamp ± to illuminate.
For more information, see the “Practical hints”
section (
page 602).

553 Operation
Tires and wheels
Direction 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.
1) The Tire and Loading Information
placard can be found on the driver’s
door B-pillar. This placard tells you im-
portant 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.
2) 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.
1Driver’s door B-pillar
Following is a discussion on how to work
with the information contained on the Tire
and Loading Information placard with re-
gards to loading your vehicle.
iSpare wheels may be mounted against the
direction of rotation (spinning) even with a unidi-
rectional tire for temporary use only until the reg-
ular drive wheel has been repaired or replaced.
Always observe and follow applicable temporary
use restrictions and speed limitations indicated
on the spare wheel.

560 Operation
Tires and wheels
Tire inflation pressure changes by approxi-
mately 1.5 psi (0.1 bar) per 18°F (10°C) of
air temperature change. Keep this in mind
when checking tire inflation pressure
where the temperature is different from
the outside temperature.
Checking tire inflation pressure
Regularly check the tire inflation pressure
at least once a month.
Check and adjust the tire inflation
pressure when the tires are cold. The tires
can be considered cold if the vehicle has
been parked for at least 3 hours or driven
less than 1 mile (1.6 km).
If you check the tire inflation pressure
when the tires are warm (the vehicle has
been driven for several miles or sitting less
than 3 hours), the reading will be
approximately 4 psi (0.3 bar) higher than
the cold reading. This is normal. Do not let
air out to match the specified cold tire in-
flation pressure. Otherwise, the tire will be
underinflated.Checking tire inflation pressure
manually
Follow the steps below to achieve correct
tire inflation pressure:
Remove the cap from the valve on one
tire.
Firmly press a tire gauge onto the
valve.
Read tire inflation pressure on tire
gauge and check against the recom-
mended tire inflation pressure on the
Tire and Loading Information placard
on the driver’s door B-pillar
(
page 553) or, if available, the tire in-
flation pressure label on the inside of
the fuel filler flap. If necessary, add air
to achieve the recommended tire infla-
tion pressure.
Warning!G
Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly,
adversely affect handling and fuel economy,
and are more likely to fail from being over-
heated.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride
comfort, wear unevenly, increase stopping
distance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road
debris, potholes etc.
Do not overload the tires by exceeding the
specified load limit or total load limit as indi-
cated on the Tire and Loading Information
placard located on the driver’s door B-pillar.
Overloading the tires can overheat them,
possibly causing a blowout. Overloading the
tires can also result in handling or steering
problems, or brake failure.

576 Operation
Tires and wheels
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, radio, and heater, to the extent that
these items are available as
factory-installed equipment (whether
installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire.
Air pressure is expressed in pounds per
square inch (psi), or kilopascal (kPa) or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.Bar
Another metric unit for air pressure. There
are 14.5038 pounds per square inch (psi)
to 1 bar; there are 100 kilopascals (kPa)
to 1 bar.
Bead
The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the
rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle
has been sitting for at least 3 hours or driv-
en no more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with stan-
dard equipment including the maximum
capacity of fuel, oil, and coolant, and, if so
equipped, air conditioning and additional
optional equipment, but without passen-
gers and cargo.DOT (Department of Transportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross Axle Weight Rating)
The GAWR is the maximum permissible
axle weight. The gross vehicle weight on
each axle must never exceed the GAWR for
the front and rear axle indicated on the
certification label located on the driver’s
door B-pillar.
GVW (G
ross Vehicle Weight)
The GVW comprises the weight of the
vehicle including fuel, tools, spare wheel,
installed accessories, passengers and
cargo and, if applicable, trailer tongue
load. The GVW must never exceed the
GVWR indicated on the certification label
located on the driver’s door B-pillar.

603 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
±The yellow engine malfunc-
tion indicator lamp comes
on while driving.A loss of pressure has been detected in the
fuel system. The fuel cap may not be closed
properly or the fuel system may be leaky.Check the fuel cap.
If it is not closed properly:
Close the fuel cap.
If it is closed properly:
Have the fuel system checked by an au-
thorized Mercedes-Benz Center.
Your fuel tank is empty.After refueling, start, turn off, and re-
start the engine three or four times in
succession.
The limp-home mode is canceled. You do
not need to have your vehicle checked.

649 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Gas cap openA loss of pressure has been detected in the
fuel system. The fuel cap may not be closed
properly or the fuel system may be leaky.Check the fuel cap (page 538).
If it is not closed properly:
Close the fuel cap.
If it is closed properly:
Have the fuel system checked by an autho-
rized Mercedes-Benz Center.
You are driving with the hood open.Stop your vehicle as soon as it is safe to do
so.
Engage the electronic parking brake
(
page 395).
Close the hood (page 542).
There is otherwise danger of an accident.

673 Practical hints
Unlocking/locking in an emergency
Mechanically releasing the electronic
parking brake
Depending on vehicle production date your
vehicle may be equipped with a mechani-
cal release device for releasing the elec-
tronic parking brake. It is located behind
the fuel filler flap next to the fuel cap.
1Protective cap
2Release tool
3Pulling
Shift the automatic transmission to P
(
page 399).
Prevent the vehicle from rolling away
by blocking a rear wheel with the wheel
chock. A wheel chock is included with
the vehicle tool kit (
page 668).
Open fuel filler flap.
Remove protective cap1.
Screw release tool2 from vehicle tool
kit clockwise 2 to 3 rotations onto re-
lease cable.
Pull release tool2 in direction of
arrow3.
The electronic parking brake is re-
leased. The red indicator lamp0
(USA only) or! (Canada only) flash-
es. The message “Parking brake See
Oper. Manual” appears on the multi-
function display.
Unscrew release tool2 from release
cable.
Reattach protective cap1.
Store release tool2 in vehicle tool kit.
After it has been unlocked, you can engage
the electronic parking brake again from
the driver’s seat.
Press the electronic parking brake han-
dle (
page 395).
iIf your vehicle is not equipped a mechanical
release device for releasing the electronic park-
ing brake contact Roadside Assistance or an au-
thorized Mercedes-Benz Center.
Warning!G
If you mechanically release the electronic
parking brake, the vehicle may start to move
on its own. Make sure that no one is in front
of or behind the vehicle. Otherwise, an acci-
dent could occur resulting in injury or fatali-
ty. Before releasing the electronic parking
brake, shift the automatic transmission to P
(
page 399) and secure your vehicle in
place using the chock from the vehicle tool
kit.
iIf the electronic parking brake is not re-
leased, pull the release tool again with more
force.

724 Technical data
Fuels, coolants, lubricants, etc.
Capacities
Vehicle components and their respective
lubricants must match. Therefore use only
products tested and approved by
Mercedes-Benz.
Please refer to the Factory Approved
Service Products pamphlet (USA only), or
inquire at an authorized Mercedes-Benz
Center.
Warning!G
Comply with all valid regulations with re-
spect to handling, storing and disposing of
service fluids. Otherwise you could endan-
ger persons or the environment.
Keep service fluids out of the reach of chil-
dren.
For health reasons, you should prevent ser-
vice fluids from coming into direct contact
with your skin or clothing.
If a service fluid is swallowed, contact a phy-
sician immediately.
ModelCapacityFuels, coolants, lubricants, etc.
Engine with oil filterS 550
S 550 4MATIC8.98 US qt. (8.5 l)Approved engine oils
S6009.51 US qt. (9.0 l)
S63 AMG9.25 US qt. (8.75 l)
S65 AMG9.51 US qt. (9.0 l)
Automatic transmissionS 550
S 550 4MATIC10.36 US qt. (9.8 l)MB Automatic Transmission Fluid
S6008.14 US qt. (7.7 l)
S63 AMG9.25 US qt. (8.75 l)
S65 AMG9.2 US qt. (8.7 l)