Audi A8 2019 Service Training page 36

ATF and MTF systems
The 0D5 transmission has three separate systems containing different types of oil:
ATF system for the planetary gearbox and
the hydraulic control unit (not subject to
routine maintenance).
MTF supply for the transfer case (gear oil
containing STURACO
maintenance).
Oil supply for the front axle drive. The new
low-viscosity axle oil is not subject to routine
maintenance and must not be mixed with
non-low viscosity axle oil. To avoid mixing
oils, the new axle oil is dyed red.
Gearbox breather
The front axle drive and the
ATF system are ventilated via
the collecting chamber. A
breather port leads from the
collecting chamber into the
bell housing. The transfer case
is ventilated via a separate
ventilation cap. When the
transmission is warming up or
cooling off, the pressure is
equalized via the transmission
vents. To allow pressure equal-
ization to take place, the venti-
lation ports must be open and
unobstructed.
Note
During transportation and when moving and/or performing work on the transmission, the axle oil and ATF may mix via the
common vent if the transmission is tilted too far. Always follow the instructions given in the repair literature.
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, not subject to routine
1)
MTF filler and inspection plug
for the transfer case
Oil reservoir
In transmissions without an MTF pump, the transfer case is lubricated by the
gears running in the MTF sump (oil sump). The oil reservoir is filled with the
gear splash oil and serves to distribute the oil.
STURACO is an oil additive which protects against excessive stresses in the
1)
center differential and thus helps to enhance ride comfort.
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Ventilation port
Vent for the
front axle drive
ATF breather
Collecting chamber
Inspection and filler plug for
front axle drive
ATF filler and
inspection plug
Transfer case vent
Leak oil drainage port for
the gear set/transfer case
double shaft seal
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