Technical service bulletin from AUDI regarding oil which is safe to use
http://www.audiusa.com/etc/medialib/cms4imp/audi2/aoa/company/aoa-specific.Par.0023.File.pdf
Erm - that is for the NORTH AMERICAN market! Our European oil specifications are considerably higher than those. If you use any non 504.00 oil, then you are highly likely to not only shorten the life of your turbo, but you will be much more likely to suffer with the 'yankie' carbon build up on the valves!
