I think I was somewhat confused. My old 2006 VW Tdi PD engine called for VW 505.01 spec which was ACEA B4. Best I can remember that had a DPF but of course no DEF system. But then when 507.00, a C3 came out it was backwards compatible with the B4 spec oil in that engine. Throw a Dexos2 vehicle in the mix and it gets more crazy. So I just go with VW 507.00 in all by vehicles now.Mid saps 5w40 is quite rare. VW just came out with a new spec called 511 which fits this criteria. 504 is very similar oil though even though it is 30 grade, it still requires 3.5 HTHS.