I have an AUDI A6 2.5 TDI 180 HP (208HP chiptuning), TIPTRONIC gearbox year 2001. please tell me what kind of oil should I use for the oil change for the engine and the gearbox? Type and quantity please. I bought MOBIL oil 5W50 (8 liters) for the engine and MOBIL ATF Premium (8liters) for the gearbox. Is it good? Thank you. A.Cotet

I recommend using only VAG Transmission Fluid. It's expensive stuff but seems to be pretty high quality and obviously perfect for your expensive Porsche Tiptronic transmission.

As for the engine fluid - you've got a European spec motor so I don't even have a clue.