Transmission slipping gears after fluid change

[dzgooner]

I changed the fluid once and skipped the 120-140F level setting part. Car started slipping gears.
I did jack the car when cold, did add 0.4L until it was dripping from fill plug (just to prevent destroying the transmission until i have access to a lift), and surprisingly the car was shifting smoothly.
Things were weird when I followed the official procedure, lift the car level, shit gears until 120F and add fluid 0.6L until drips from level plug, now it's slipping gears even worse than before.

Question is, does this make any sense? I mean can transmission shifts bad on a correct fluid level and it will adjust or should i remove the 0.6L as i'm overfilled now? pretty confused here...

 

[Glasman888]

Overfilling causes slipping. The fluid foams and can't build pressure.
You overfilled it when you added the 0.6L hot. The level was already correct from your first attempt.
Drain out that extra 0.6L. Let it drip from the fill hole when the car is cold and level. This will very likely fix the slipping.

 

[NC356]

Glasman,
Do you mean drip from the level standpipe?