MERCEDES-BENZ S-Class 2008 W221 Comand Manual
Page 581 of 801
580 OperationEngine compartment
Using a rag, turn cap1 slowly approx-
imately one half turn counterclockwise
to release any excess pressure.
Continue turning the cap counterclock-
wise and remove it.
The coolant level is correct if the level
for cold coolant: reaches the white
marking (plastic bridge) inside the cool-
ant expansion tank
for warm coolant: is approximately
0.6 in (1.5 cm) higher
Add coolant as required.
Replace and tighten cap1.
For more information on coolant, see the
“Technical data” section (
page 771). Windshield washer system and
headlamp cleaning system
The washer fluid reservoir is located on the
left-hand side of the engine compartment
when looking in the direction of travel. It
supplies the windshield washer system
and headlamp cleaning system with wash-
er fluid.Example illustration S 550 with Airmatic1Cap
Vehicles with ABC*1Cap
Fluid for the windshield washer system and
the headlamp cleaning system is supplied
from the windshield washer reservoir. It
has a capacity of approximately 6.87 US qt
(6.5 l).
During all seasons, add MB Windshield
Washer Concentrate “MB SummerFit” to
water. Premix the windshield washer fluid
in a suitable container.
Page 582 of 801
581 Operation
Engine compartment
To open washer fluid reservoir: Pull
tab of cap1 upward.
Refill the reservoir with MB Windshield
Washer Concentrate and water (or
commercially available premixed wind-
shield washer solvent/antifreeze, de-
pending on ambient temperatures).
To close washer fluid reservoir:
Press cap1 onto filler hole until it en-
gages.
For more information, see “Windshield
washer system and headlamp cleaning
system” (
page 774).
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.
!
Always use washer solvent/antifreeze
where temperatures may fall below freezing
point. Failure to do so could result in damage to
the washer system/reservoir.
Only use washer fluid which is suitable for plastic
lenses. Improper washer fluid can damage the
plastic lenses of the headlamps.
Do not use distilled or de-ionized water in the
washer fluid reservoir. Otherwise, the washer
fluid level sensor could be damaged.
Page 583 of 801
582 OperationTires and wheelsContact an authorized Mercedes-Benz
Center for information on tested and
recommended rims and tires for summer
and winter operation. They can also offer
advice concerning tire service and
purchase.
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 and
damage to the tire beads.
If vehicle is heavily loaded, check tire
inflation pressure and correct as
required.
Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths of less than
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. Contact an authorized
Mercedes-Benz Center for further informa-
tion. If incorrectly sized rims and tires are
mounted:
The wheel brakes or suspension
components 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 worn to minimum tread depth,
or if the tires have sustained damage, re-
place them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can
result in the bolts loosening and possibly an
accident.
Retreaded tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on re-
treads. The operating safety of the vehicle
cannot be assured when such tires are used.
Page 584 of 801
583 Operation
Tires and wheels
Tire care and maintenance
Regularly check the tire inflation pressure
at least once a month. For more informa-
tion on checking tire inflation pressure,
see “Recommended tire inflation pres-
sure” (
page 590).Tire inspection
Every time you check the tire inflation
pressure, you should also inspect your
tires for the following:
excessive treadwear (
page 584)
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 degrade over time
even if never used, and thus should be in-
spected 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
6 years, regardless of the remaining tread.
Page 585 of 801
584 OperationTires and wheelsTread depth
Do not allow your tires to wear down too
far. Adhesion properties on wet roads are
sharply reduced at tread depths of less
than
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 1/16in (1.6 mm), at which point the
tire is considered worn and should be re-
placed.
Recommended minimum tire tread depth:
Summer tires
1/8in (3 mm)
Winter tires
1/6in (4 mm)
1TWI (T
readW
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. Pro-
tect tires from contact with oil, grease and gaso-
line.
!
Never use a round nozzle to power wash
tires. The intense jet of water can result in dam-
age to the tire.
Always replace a damaged tire.
Page 586 of 801
585 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.
i
Spare 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.
Page 587 of 801
586 OperationTires and wheelsTire and Loading InformationTire and Loading Information placard
1Load limit information on the Tire and
Loading Information placard
The Tire and Loading Information placard
showing the load limit information is locat-
ed on the driver’s door B-pillar.
Locate the statement “The combined
weight of occupants and cargo should
never exceed XXX kilograms or XXX
lbs.” on the Tire and Loading Informa-
tion placard.
The combined weight of all occupants,
cargo/luggage and trailer tongue load
(if applicable) should never exceed the
weight referenced in that statement.Seating capacity
The seating capacity gives you important
information on the number of occupants
that can be in the vehicle. Observe front
and rear seating capacity. The Tire and
Loading Information placard showing the
seating capacity is located on the driver’s
door B-pillar (
page 585).
Warning!
G
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 on the driver’s door B-pillar. Over-
loading the tires can overheat them, possi-
bly causing a blowout. Overloading the tires
can also result in handling or steering prob-
lems, or brake failure.i
Data shown on Tire and Loading Information
placard example are for illustration purposes
only. Load limit data are specific to each vehicle
and may vary from data shown in the illustration
below. Refer to Tire and Loading Information
placard on vehicle for actual data specific to your
vehicle.
i
Data shown on Tire and Loading Information
placard example are for illustration purposes
only. Seating capacity data are specific to each
vehicle and may vary from data shown in the il-
lustration below. Refer to Tire and Loading Infor-
mation placard on vehicle for actual data specific
to your vehicle.
Page 588 of 801
587 Operation
Tires and wheels
1Seating capacity information on the
Tire and Loading Information placard
Steps for determining correct load limit
The following steps have been developed
as required of all manufacturers under
Title 49, Code of U.S. Federal Regulations,
Part 575 pursuant to the “National Traffic
and Motor Vehicle Safety Act of 1966”.
Step 1
Locate the statement “The combined
weight of occupants and cargo should
never exceed XXX kg or XXX lbs.” on
your vehicle’s Tire and Loading Infor-
mation placard.Step 2
Determine the combined weight of the
driver and passengers that will be
riding in your vehicle.
Step 3
Subtract the combined weight of the
driver and passengers from XXX kilo-
grams or XXX lbs.
Step 4
The resulting figure equals the avail-
able amount of cargo and luggage load
capacity. For example, if the “XXX”
amount equals 1400 lbs and there will
be five 150 lbs passengers in your
vehicle, the amount of available cargo
and luggage load capacity is 650 lbs
(1 400 – 750 (5 x 150) = 650 lbs).
Step 5
Determine the combined weight of
luggage and cargo being loaded on the
vehicle. That weight may not safely
exceed the available cargo and luggage
load capacity calculated in step 4.Step 6 (if applicable)
If your vehicle will be towing a trailer,
load from your trailer will be trans-
ferred to your vehicle. Consult this
manual to determine how this reduces
the available cargo and luggage load
capacity of your vehicle (
page 589).
The following table shows examples on
how to calculate total and cargo load
capacities with varying seating configura-
tions and number and size of occupants.
The following examples use a load limit
of 1 500 lbs. This is for illustration
purposes only. Make sure you are using
the actual load limit for your vehicle stated
on the vehicle’s Tire and Loading
Information placard (
page 586).
Page 589 of 801
588 OperationTires and wheelsThe higher the weight of all occupants, the
less cargo and luggage load capacity is
available.
For more information, see “Trailer tongue
load” (
page 589).
Example
Combined
weight limit
of occu-
pants and
cargo from
Tire and
Loading
Information
placard
Number of
occupants
(driver and
passengers)
Seating
configura-
tion
Occupants weight
Combined
weight of all
occupants
Available cargo/luggage and trailer
tongue weight (total load limit from
Tire and Loading Information
placard minus combined weight of
all occupants)
1
1 500 lbs
5
front: 2
rear: 3
Occupant 1: 150 lbs
Occupant 2: 180 lbs
Occupant 3: 160 lbs
Occupant 4: 140 lbs
Occupant 5: 120 lbs
750 lbs
1 500 lbs – 750 lbs = 750 lbs
2
1 500 lbs
3
front: 1
rear: 2
Occupant 1: 200 lbs
Occupant 2: 190 lbs
Occupant 3: 150 lbs
540 lbs
1 500 lbs – 540 lbs = 960 lbs
3
1 500 lbs
1
front: 1
Occupant 1: 150 lbs
150 lbs
1 500 lbs – 150 lbs = 1 350 lbs
Page 590 of 801
589 Operation
Tires and wheels
Certification label
Even after careful determination of the
combined weight of all occupants, cargo
and the trailer tongue load (if applicable)
(page 589) as to not exceed the permis-
sible load limit, you must make sure that
your vehicle never exceeds the Gross Vehi-
cle Weight Rating (GVWR) and the Gross
Axle Weight Rating (GAWR) for either the
front or rear axle. You can obtain the
GVWR and GAWR from the certification la-
bel. The certification label can be found on
the driver’s door B-pillar, see “Technical
data” (
page 748).Gross Vehicle Weight Rating (GVWR): The
total weight of the vehicle, all occupants,
all cargo, and the trailer tongue load
(
page 589) must never exceed the
GVWR.
Gross Axle Weight Rating (GAWR): The to-
tal allowable weight that can be carried by
a single axle (front or rear).
To assure that your vehicle does not ex-
ceed the maximum permissible weight
limits (GVWR and GAWR for front and rear
axle), have the loaded vehicle (including
driver, passengers and all cargo and, if ap-
plicable, trailer fully loaded) weighed on a
suitable commercial scale.Trailer tongue load
The tongue load of any trailer is an impor-
tant weight to measure because it affects
the load you can carry in your vehicle. If a
trailer is towed, the tongue load must be
added to the weight of all occupants riding
and any cargo you are carrying in the
vehicle. The tongue load typically is 10% of
the trailer weight and everything loaded in
it.
Your Mercedes-Benz has been designed
primarily to carry passengers and their
cargo. Mercedes-Benz does not recom-
mend trailer towing with your vehicle.