Got another question about my s4 TII . in an naturally aspirated this wouldnt matter but seeing as its a turbo i was wondering if when i drain the oil if the oil cooler is still gonna be full and if so should i purge it or something , also any additives i should put in?

 

It's no different from an NA car. The oil cooler has roughly a 0.6 quart (from memory) capacity, so you can drain it during an oil change if you like. But you'll find it's not the easiest thing to do.

 

Don't worry with that. Just drain the oil like a normal car.