I sold my Aurion and bought a diesel bmw. It has theZF 8 speed automatic that is has lifetime fluid like the Aurions. I dropped the pan to replace the filter and fluid. The filter is built into the pan so both get replaced. The pan has a rubber seal made into it so no gasket needed. It had 4 magnets and at 135,000 km they has a thin coating of metallic sludge - less than my aurion had when i first dropped its pan - at 195,000km though. New fluid is honey colour and the old fluid was dark but on a tissue it wasn’t very black. The trans was very smooth before the change but it’s different to others. Eg in neutral it barely rolls forward.
I thought 8 gears was silly but its a great match for the 2.0 turbo diesel. It also got 900km on the first tank, i think the trans was a big part of that.
A painful aspect of the job was the underbody covers which add aero efficiency but are an extra step in the job.