Hi all,

I'm planning to buy an A6 or A4 (haven't completely decided yet but my heart goes for A6). I have never owned Audi before so I am looking for some help and advise to what to check or look out for. Also would like to get some opinion on the car.

My main choice would be 2009 or 2010 A6 S-Line 2.0TDI (would like to get 170BHP) Automatic.

I have some questions:
-I have a friend who has an A6 2012 which got big problem with the automatic gearbox and needed to replace the transmission completely. Should I stay away from automatic or what to watch out for?
-I have heard that these 2.0TDI engines had a flaw with the oil pump which had a drive shaft issue. When the oil pump became a problem it did not provide enough oil pressure causing big damage to turbo and engine. Is this true and if yes which models and years are affected? Is there any way to find out if the engine in the car what I will want to buy had got this damage already?
-Should I stay away from high mileage sales? If yes what would be the max that should be still OK to buy?
-Are there any problems with these cars what I should be aware of?
-Is A6 a better choice for me or should I consider the A4? (I mean is there any difference other than the size?) Does A6 have more extras etc.? (this might be a stupid question but please forgive me as I don't know too much about these cars!)


Thank you for all the advices in advance,
Regards,
Pal