Vehicles with an ATF main filter: Loosen the bolt "arrow" and disconnect the ATF line "1" from the transmission. The ATF line to the ATF main filter "pos. 2" does not need to be removed if the ATF main filter itself is not removed.
Remove bolt "1." Disconnect the ATF line from the ATF filter by removing the clamp "arrow." If the ATF filter cannot be removed, disregard "pos. 2.".
Cars with a replaceable ATF filter: Unscrew the bolt "arrow" and disconnect the ATF lines "1, 2" from the gearbox.
All
Blow out the ATF lines and the ATF cooler with compressed air (max 10 bar). If, when draining the ATF, it is found to be heavily contaminated, additionally flush the radiator and ATF lines with clean ATF.
For vehicles with an ATF main filter: After replacing the gearbox or if the ATF is heavily contaminated, the ATF main filter should be changed.
For vehicles with a replaceable ATF filter: Replace the replaceable ATF filter if the ATF is heavily contaminated. For vehicles with a replaceable ATF filter, the filter is included with the new transmission. The replaceable ATF filter must be replaced with every ATF change. Install the ATF lines.
This publication is borrowed from the resource AUDIMANUAL