Mercedes-Benz GLK-Class 2015 Owners Manual - Manual (Page 378)

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
i Diesel 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
Model Total capacity
GLK 250 BlueTEC 7.3 US gal
(27.5 l)
376
Service products and filling capacities
Tec
hni
ca
ldata