Audi A8 2018 Owner's Manual page 280

Checking and Filling
If you must add coolant, use a mixture of water
and coolant additive . Mixing the coolant additive
with distilled water is recommended.
Coolant additive
The coolant additive is made of anti-freezing and
corros ion protection agents. Only use the fo llow-
ing coolant additives .
Coolant additive Specification
Gl2evo
TL 774 L
Gl2 ++
TL 774
G
Gl3
TL 774 J
These additives may be mixed wit h each othe r.
The amount of coolant additive that needs to be
mixed with water depends on the climate where
the vehicle will be operated. If the coolant addi -
tive percentage is too low, the coolant can free ze
and damage the engine.
Coolant addi- Freeze protec-
tive tion
Warm regions min. 40%, min. -13 °F
max. 45%
(-25 °()
Cold regions min. 50%,
max. -40 °F
max. 55% (-40 °C)
@
Note
- Before the start of winter, have an author-
ized Audi dealer or authorized Audi Service
Facility check if the coolant additive in your
vehicle matches the percentage appropriate
for the climate. This is especially important
when driving in colder climates .
- If the appropriate coolant additive is not
available in an emergency, do not add any
other addit ive for risk of damaging the en-
gine . If this happens, only use water and re-
store the correct mixture rat io with the
specified coolant additive as soon as possi-
ble.
- Only refill with new coolant.
- Radiator sealant must not be mixed with
the coolant.
278
Adding coolant
Fig. 260 Eng ine compar t ment : coolant expansion tank
cover
Observe the safety precautions ~ .&, in Working
in the engine compartment on page 2 72.
Checking the engine coolant level
~ Park the vehicle on a level surface .
~ Switch the ignit ion off.
~ Read the coolant level on the coolant expansion
tank ~ page 2 74. The coolant level must be be-
tween the MIN and MAX markings when the en-
gine in cold. When the engine is warm it can be
slightly above the
MAX
marking,
Adding coolant
Requirement: th ere must be a residual amount of
coolant in the expansion tank ~ (©).
~ Let the engine cool down .
~ Place a clot h over the coolant expans ion tank
cap and unscrew the cap counterclockwise
~.&. -
~ Add coolant mixed in the correct ratio
~ page 277 up to the MAX marking.
~
Make sure that the f luid level remains stab le.
Add more coolant if necessary .
~ Close the cap securely .
Coolant loss usually indicates there is a leak . Im -
mediate ly drive your vehicle to an authorized
Audi dealer or authorized Audi Service Facility
and have the cooling system inspected. If the
cooling system is not leaking, a loss can come
from the coolant boiling t hrough overheat ing
and being pushed out of the cooling system .