Glisse

If it really is a B9 A5, then it is using the Audi designed DL382 transmission.

There are two completely separate oil systems - one for the mechatronics, one for the gears. They use different fluid types. The mechatronics side requires 3.5 litres if replacing fluid (4.35 for a new build up). The gear set requires 3.8 litres. No surprise you only managed to squeeze in 4 litres. Whoever told you 7 litres perhaps added up the two sides - but they are different fluid types.

See here:
https://www.audiworld.com/forums/a4-...hange-2945427/

Better to have understood the transmission and the process before starting the job, I would have thought. Good luck.