AB's new GQ is finally here

[mudski]

Yeah wow this is interesting. As we were so sure it was just the turbo at fault. We can only hope the the smaller oil drain diameter is restricting flow causing it pressurise internally and leak past the seal.
Not sure if this is of any help, or you have already done this but heres a few links for you. There might be some things here you might not have checked????
http://www.turbos.bwauto.com/product...eshooting.aspx
http://turbolabofamerica.com/causes-...burn-oil-find/
http://www.full-race.com/catalog_ima...leshooting.pdf