Further information on engine oil
( Y page 354).XReplace cap : on the filler neck and
tighten clockwise.
Ensure that the cap locks into place
securely.
Checking and adding other service
products
Checking the coolant level
Only check the coolant level when the vehicle
is on a level surface and the engine has cooled
down.
XTurn the SmartKey to position
2 (Y page 149) in the ignition lock.
On vehicles with KEYLESS-GO, press the
Start/Stop button twice ( Y page 149).XCheck the coolant temperature gauge in
the multifunction display.
The coolant temperature must be below
158 ‡ (70 †).GWarning
In order to avoid any potentially serious burns:
R 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 display indicates
that the coolant is overheated.
R do not remove the pressure cap on the
coolant reservoir if the coolant temperature
is above 158 ‡ (70 †). Allow the engine to
cool down before removing the cap. The
coolant reservoir contains hot fluid and is
under pressure.
R using a rag, slowly turn the cap
approximately 1
/ 2 turn to relieve excess
pressure. If opened immediately, scalding
hot fluid and steam will be blown out under
pressure.
R do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts.XSlowly turn cap : half a turn counter-
clockwise and allow excess pressure to
escape.XTurn cap : further counter-clockwise and
remove it.
If the coolant is at the level of marker bar
= in the filler neck when cold, there is
enough coolant in coolant expansion
tank ;.
If the coolant is approximately 0.6 in
(1.5 cm) higher when warm, there is
enough coolant in coolant expansion
tank ;.XIf necessary, add coolant which has been
tested and approved by Mercedes-Benz.XReplace cap : and turn it clockwise as far
as it will go.
For further information on coolant, see
( Y page 355).
Windshield washer system/headlamp
cleaning system
The washer fluid reservoir is used for both the
windshield washer system and the headlamp
cleaning system.
GWarning
Washer solvent/antifreeze is highly
flammable. Do not spill washer solvent/
antifreeze on hot engine parts, because it may
ignite and burn. You could be seriously
burned.
Engine compartment281Maintenance and careBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 281Z
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
Do not use tires until they are excessively
worn as the tire traction on wet road surfaces
decreases significantly when the tread depth
is less than 1
/ 8 in (3 mm).
Tread wear indicators (TWI) are required by
law. Six indicators are positioned over the tire
tread. They are visible as soon as a tread
depth of approximately 1
/ 16 in (1.6 mm) is
reached. If this is the case, the tire is so worn
that it must be replaced.
The recommended tread depth for summer
tires is at least 1
/ 8 in (3 mm). The
recommended tread depth for winter tires is
at least 1
/ 6 in (4 mm).
Bar marking
: for tread wear is integrated
into the tire tread.
Storing tires
Store tires that are not being used in a cool,
dry and preferably dark place. Protect the
tires from contact with oil, grease and fuel.
Cleaning tires
! Do not use a high pressure jet with
circular jet nozzles (concentrated-power
jets) to clean the tires. The high pressure
of the water jet could damage the tires.
Always replace damaged tires.
Tire pressures
Tire pressure specifications
GWarning
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 overheated.
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 as indicated on the Tire
and Loading Information placard 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.
You will find a table of recommended tire
pressures on the Tire and Loading
Information placard on the B-pillar on the
driver's side ( Y page 330). You will find a
table of tire pressures for various operating
conditions on the inside of your vehicle's fuel
filler flap.
To test tire pressure, use a suitable pressure
gauge. The outer appearance of a tire does
not permit any reliable conclusion about the
tire pressure. On vehicles installed with the
electronic tire pressure monitor, the tire
pressure can be checked in the on-board
computer.
GWarning!
Should the tire pressure drop repeatedly:
322Tire pressuresTires and wheels
BA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 322
Fuel
Important safety notesGWarning!
Fuel is highly flammable. Fire, naked flames
and smoking are therefore prohibited when
handling fuels.
Switch off the engine and the auxiliary heating
before refueling.
GWarning!
Gasoline and diesel fuels are highly flammable
and poisonous. They burn violently and can
cause serious injury.
Never allow sparks, flames or smoking
materials near gasoline or diesel fuel!
Turn off the engine before refueling.
Whenever you are around gasoline or diesel
fuel, avoid inhaling fumes and any skin or
clothing contact. Extinguish all smoking
materials.
Direct skin contact with fuels and the
inhalation of fuel vapors are damaging your
health.
Premium-grade unleaded gasoline
! To ensure the longevity and full
performance of the engine, only premium-
grade unleaded gasoline must be used.
If premium-grade unleaded gasoline is
unavailable and regular gasoline is used,
observe the following precautions:
R only fill the fuel tank to half full with
regular unleaded gasoline and add the
rest as soon as possible with premium-
grade unleaded gasoline.
R do not drive at the maximum speed.
R avoid sudden acceleration.
R when the vehicle is carrying a light cargo,
e.g. two passengers without luggage, do
not allow the engine to rev above
3000 rpm.
R when the vehicle is fully loaded or being
operated in mountainous terrain, do not
depress the accelerator pedal further
than 2
/ 3 of the pedal travel.
Fuel requirements
Gasoline engines
Use only premium-grade unleaded gasoline.
The octane number should be at least 91.
Details can be found on the gas pump. The
octane number is the average value of the
Research Octane Number (RON) and Motor
Octane Number (MON): (RON + MON) / 2,
also known as knock resistance.
Reformulated Gasoline (RFG) and/or
unleaded gasoline with additives can be used
if the concentration of the additives in the fuel
does not exceed 10%, e.g.:
R Ethanol
R TAME
R ETBE
R IPA
R TBA
For MTBE, the concentration should not
exceed 15%.
The concentration of methanol in gasoline
including other additives must not exceed 3%.
Using mixtures of methanol and ethanol is not
permitted. Gasohol, a mixture of 10% ethanol
and 90% unleaded gasoline can be used.
All of these mix fuels must fulfill the fuel
requirements, e.g.:
R knock resistance
R boiling point
R vapor pressure
Diesel engines – important safety
information
! Only use commercially available ULTRA-
LOW SULFUR DIESEL FUEL (ULSD, 15 ppm
MAXIMUM SULFUR) that meets the
ASTM D975 standard. Failure to use
ULTRA-LOW SULFUR DIESEL FUEL (ULSD)
can severely damage the vehicle's exhaust
gas aftertreatment system.
352Service products and capacitiesTechnical data
BA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 352