What he ^ said or Castrol Syntec 5w-40, the t6 is easy to find.
I'm using Amsoil European Full SAPS 5w-40 5-6000 mile oil change intervals.
193k, 5/20/12 new ej257 short block, 8/20/11 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
Engine Build - Click Here