5w40 mobile 1 synthetic with 1quart of Original Lucas Oil Stabilizer, Turbos like to leak with thin oil. Never had an issue. If you want best gas mileage sure run 5w20
you want protection for your investments then put thicker oil.
2012 Audi Q7 TDI S Line ABTuning 391whp588wtq
01 Turbo Focus 300+ whp
2012 Focus 19" Niches, AEM CAI, F2 Race Header, 3" Borla Dual Exit, H&Rs, Eibach Sways 183whp157wtq