Yeah I’m still under the warranty, so I won’t be using 0W-20.. isn’t that a little thin? I have a 2018 so 5W-40 is what the dealer will put in the car if you ask for an oil change. Technically, 0W-40 isn’t listed in the user manual but it‘s on the approved VW list for 2018 and others have used it so I figure there won’t be any issues. 0W-20 though.. no thanks lol. That sounds risky.Avoid this oil like plague. ACEA A3/B4 is a high ash (SAPS) oil which is detrimental to GDI engines intake valves.
Much better choice is low saps oils ACEA C1 or C4. Also consider thinnest base oil possible like 0w-20 due to their higher NOACK which decreases deposit formation on intake valves due to their increased volatility / increased evaporative cleaning. Higher viscosity oils have usually lower NOACK (decreased volatility and evaporation) which contributes to increased deposit formation.
I only run 0w-20 ST HM SN PLUS with 5K OCI with great results. Mobil1 EP 0w-20, PPPP 0w-20 are also great choices for GDI engines with high quality base oils.
The latest API SN PLUS was specifically developed for turbocharged engines to protect against LSPI so look for oil with that spec.
And what do you mean by high ash? Is it any higher than Castrol 5W-40? If not significantly then I’m not too concerned.
I think about this way.. something that is dirty, can always be cleaned (e.g. intake valves). Something that is worn out, well, can’t be un-worn out. I’m not gonna use a really thin oil that’ll wear out the engine more, just to (maybe) keep the intake valves cleaner.