DEF
Important safety notes Comply with the important safety notes for
service products when handlin gDEF
(Y page 365).
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 vapo rmay be released.
Ammonia vapors have a pungen todor and are
particularly irritating to the skin, to mucous
membranes and to the eyes. You may
experience 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
approximately 12
‡(-11 †). The vehicl eis
delivered from the factory equipped with a
DEFp reheating 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
aftertreatment system.
Purity !
Impurities in DEF (e.g. due to other
service 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
malfunctions in the BlueTEC exhaust gas
aftertreatment 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) Engine oil
General notes !
Never use engine oil or an oil filter of a
specificatio nothe rthan is necessary to
fulfill the prescribed service intervals. Do
not change the engine oil or oil filter in
order to achieve longer replacement
intervals than those prescribed. You could
otherwise cause engine damage or damage
to the exhaust gas aftertreatment.
Follow the instructions in the service
interval display regarding the oil change.
Otherwise, you may damage the engine and
the exhaust gas aftertreatment.
When handling engine oil, observe the
important safety notes on service products
(Y page 365).
The engine oils are matched to the
performance of Mercedes-Benz engines and
service intervals. You should therefore only
use engine oils and oil filters that are
approved for vehicles with maintenance
systems.
For a list of approved engine oils and oil filters,
consult an authorized Mercedes-Benz Service products and fillingc
apacities
369Technical data Z
Center. Or visit the website
http://bevo.mercedes-benz.co
m.
The table shows which engine oils have been
approved for your vehicle. Model Engine
model MB
Approval GLK 350
BlueEFFICIENCY
GLK 350
4MATIC
BlueEFFICIENCY
276 229.5
GLK 250
BlueTEC
651 228.51,
229.31,
229.51 i
MB approval is indicated on the oil
containers.
Filling capacities The following values refer to an oil change
including the oil filter.
Model Capacity
All models
6.9 US qt
(6.5 l) Additives
!
Do no tuse any additives in the engine oil.
This could damage the engine.
Engine oil viscosity Viscosity describes the flow characteristics
of a fluid. If an engine oil has a high viscosity, this means that it is thick; a low viscosity
means that it is thin.
Select an engine oil with an SAE classification
(viscosity) suitable for the prevailing outside
temperatures. The table shows you which
SAE classifications are to be used. The low-
temperature characteristics of engine oils
can deteriorate significantly, e.g. as a result
of aging, soot and fuel deposits. It is therefore
strongly recommended that you carry out
regularo il changes using an approved engine
oil with the appropriate SA Eclassification. Brake fluid
G
WARNING
The brake fluid constantly absorbs moisture
fro mt he air. This lowers the boiling point of
the brake fluid. If the boiling point of the brake
fluid is too low, vapor pockets may form in the
brake system when the brakes are applied
hard. This would impair braking efficiency.
There is a risk of an accident.
You should have the brake fluid renewed at
the specified intervals.
When handling brake fluid, observe the
important safety notes on service products
(Y page 365).
The brake fluid change intervals can be found
in the Maintenance Booklet.
Only use brake fluid approved by Mercedes-
Benz according to MB Approval 331.0.
Information about approved brake fluid can
be obtained at any qualified specialist
workshop or on the Internet at
http://bevo.mercedes-benz.com.
i Have the brake fluid regularly replaced at
a qualified specialist workshop and the
replacement confirmed in the Maintenance
Booklet. 370
Service products and fillingc
apacitiesTechnical data
