If you or others come into contact with fuel,
observe the following:R Wash away fuel from skin immediately
using soap and water.
R If fuel comes into contact with your eyes,
immediately rinse them thoroughly with
clean water. Seek medical assistance with-
out delay.
R If fuel is swallowed, seek medical assis-
tance without delay. Do not induce vomit-
ing.
R Immediately change out of clothing which
has come into contact with fuel.
GWARNING
Electrostatic buildup can create sparks and
ignite fuel vapors. There is a risk of fire and
explosion.
Always touch the vehicle body before opening
the fuel filler flap or touching the fuel pump
nozzle. Any existing electrostatic buildup is
thereby discharged.
GWARNING
Vehicles with a diesel engine:
If you mix diesel fuel with gasoline, the flash
point is lower than that of pure diesel fuel.
When the engine is running, exhaust system
components could overheat without being
noticed. There is a risk of fire.
Never refuel with gasoline. Never mix gasoline with diesel fuel.
! Do not use diesel to refuel vehicles with a
gasoline engine. Do not switch on the igni-
tion if you accidentally refuel with the
wrong fuel. Otherwise, the fuel will enter
the fuel system. Even small amounts of the wrong fuel could result in damage to the
fuel system and the engine. Notify a quali-
fied specialist workshop and have the fuel
tank and fuel lines drained completely.
! Do not use gasoline to refuel vehicles with
a diesel engine. Do not switch on the igni-
tion if you accidentally refuel with the wrong fuel. Otherwise, the fuel will enter
the fuel system. Even small amounts of the
wrong fuel could result in damage to the
fuel system and the engine. The repair
costs are high. Notify a qualified specialist
workshop and have the fuel tank and fuel
lines drained completely.
! Overfilling the fuel tank could damage the
fuel system.
! Take care not to spill any fuel on painted
surfaces. You could otherwise damage the
paintwork.
! Use a filter when refueling from a fuel can.
Otherwise, the fuel lines and/or injection
system could be blocked by particles from
the fuel can.
Do not get into the vehicle again during the
refueling process. Otherwise, electrostatic
charge could build up again.
If you overfill the fuel tank, fuel could spray
out when the fuel pump nozzle is removed.
For further information on fuel and fuel quality ( Y page 373).
For further information on fuel and fuel qual-
ity, see the separate operating instructions.
Refueling
General information
The fuel filler flap is unlocked or locked auto-
matically when you open or close the vehicle with the SmartKey or with KEYLESS-GO.
The position of the 8 fuel filler cap is dis-
played in the instrument cluster. The arrow
next to the filling pump indicates the side of
the vehicle.
Refueling163
Driving and parking
Z
Bio-diesel – FAME (fatty acid methyl ester)Mercedes-Benz USA approves the use of bio-diesel B5 for all BlueTEC diesel engines. The
concentration of bio-diesel in the ULSD may
not exceed 5% by volume.
Pure bio-diesel and diesel fuel with a higher
percentage of bio-diesel, such as B20, can
damage the engine and the fuel system. For
this reason, they are not approved.
For more information, consult the gas station
staff. The bio-diesel B5 label on the gasoline
pump must clearly state that the standard for
ULSD has been fulfilled. If the label is not
clear, do not refuel the vehicle.
Do not refuel your vehicle with fuels unless
they have been approved by Mercedes-Benz.
Information on refueling ( Y page 163).
Low outside temperatures
iDiesel fuel with improved cold flow prop-
erties is available during the winter months. Further information about fuel properties
can be obtained from oil companies, e.g. at gas stations.
DEF
Important safety notes
Comply with the important safety notes for
service products when handling DEF
( Y page 373).
DEF is a water-soluble fluid for the exhaust
gas aftertreatment of diesel engines. It is: R not poisonous
R colorless and odorless
R not flammable
When you open the DEF container, small
amounts of ammonia vapor may be released.
Ammonia vapors have a pungent odor and are particularly irritating to the skin, to mucous
membranes and to the eyes. You may expe-
rience a burning sensation in your eyes, nose and throat. Coughing and watering of the
eyes are possible. Do not inhale ammonia vapors. Fill the DEF
tank only in well-ventilated areas.
Low outside temperatures
DEF freezes at a temperature of approx-
imately 12 ‡ (-11 †). The vehicle is delivered
from the factory equipped with a DEF pre-
heating system. Winter operation can thus be guaranteed even at temperatures below 12 ‡
(-11 †).
Additives
! Only use DEF in accordance with ISO
22241. Do not use additives with DEF and
do not dilute DEF with water. This may
destroy the BlueTEC exhaust gas after-
treatment system.
Purity
! Impurities in DEF (e.g. due to other ser-
vice products, cleaning agents or dust) lead to:
R increased emission values
R damage to the catalytic converter
R engine damage
R malfunctions in the BlueTEC exhaust gas
aftertreatment system
Assuring the purity of DEF is particularly
important with respect to avoiding malfunc-
tions in the BlueTEC exhaust gas aftertreat-
ment system.
If DEF is pumped out of the DEF tank, e.g.
during repair work, it must not be returned to
the tank. The purity of the fluid can no longer
be guaranteed.
Filling capacities
ModelTotal capacity
GLK 250 BlueTEC
4MATIC7.3 US gal (27.5 l)
376Service products and filling capacities
Technical data
