Lots of opinions on oil - that is for sure.  For a brief period I was using
10 W 60 synthetic but last summer after getting some work done on my engine
at a well known VW shop - one of the mechanics showed me a sample of the
oil which did not look uniform and told me they changed it back to 20W 50
non synthetic.  This place has a good reputation and services both Audis
and VWs including Vanagons and has lots of synthetic oil available - so it
is curious why they went back to using conventional on my Syncro.  In fact
any place I have taken my van for servicing where the oil has had to be
changed - it has always been conventional oil that it has been refilled
with.  Perhaps a cost savings measure - or perhaps what is best for these
old motors?

Bruce

On Sun, Aug 7, 2022 at 9:15 AM OlRivrRat <OlRivrRat@comcast.net> wrote:

>         I always get curious, when I hear of NonSynthetic 20w50 being used
> in
>
> a Vanagon H2OBoxer Eng, as to what prompts the user to do that ~
>
>
>
> > On 7 Aug , 2022, at 9:41 AM, Dan N <dn92610@GMAIL.COM> wrote:
> >
> > thank you Dennis,
> >
> > I wonder if there's something to do with the oil grade they recommend
> with
> > the RPM of the engines... On my ML430 suv it's about 2K rpm at 70mph...
> On
> > the vanagon it's 4K at 70mph. At 55mph it's about under 2K rpm for the
> suv
> > and about 3K rpm for the vanagon. The suv uses 5W40 synthetic, I use
> > non-synthetic 20W50 on the vanagon.
> >
> > On Sun, Aug 7, 2022 at 7:37 AM Dennis Haynes <d23haynes57@hotmail.com>
> > wrote:
> >
> >> Recently there was some discussion on engine oil. So I'll add more
> >> thoughts to the discussion.
> >> Recently I acquired a 2022 GMC Sierra Crew Cab, Denali. Has the 6.2L and
> >> 10 speed Allison. Will soon be having its 1st oil change done. Part of
> GM's
> >> plan to improve fuel economy is the use of low viscosity lubricants. The
> >> engine calls for 0w-20, the transmission use special low viscosity ATF,
> and
> >> even the axles call for 75w-80. I having a hard time wrapping my head
> >> around using the 0w-20 oil for an engine of this horsepower. To add to
> the
> >> confusion the hopped version of this engine for the Corvette calls for
> >> different oil.
> >>
> >> So doing some research I learned something that I never gave thought to.
> >> Engine oils contribution to an engine going into pre-ignition. Makes
> sense
> >> given some thought. There is always some oil on the cylinder walls and
> some
> >> part becomes part of the combustion process. For the Waterboxer this is
> >> relevant as there is also some oil laying in the bottom of the cylinder.
> >> For my engine it has active fuel management, (AFM). Glorified cylinder
> >> deactivation. Under certain load and speed conditions the cylinders get
> >> deactivated via a dance of turning off the injectors, and de-activating
> the
> >> valves. In this state oil that gets past the rings isn't burning off.
> >>
> >> GM addresses this as part of their Dexos specifications. The oils
> >> contribution to detonation is also of concern for engines that are
> direct
> >> injected and turbo charged.
> >> So to add to the confusion there is Dexos 1, generation 1, 2, and now 3,
> >> and Dexos 2. Now one would think that Dexos 2 would be the later or
> >> improved spec. It is not. Dexos 2 is for europeant vehicles which
> addresses
> >> that many European vehicles are Diesels. The performance for spark
> ignition
> >> engines is actually lower.  The GM specs also include other ratings that
> >> also include fuel economy. Oils that carry the Dexos 1, generation 2 or
> 3
> >> rating is limited.
> >>
> >> How does this apply to us? There are a number of folks that think heavy
> >> duty Diesel oils are a better choice for the Waterboxer. The
> pre-ignition,
> >> detonation control is just another consideration for using oils that are
> >> designed for gasoline, not diesel engines. Pre-ignition is the cause of
> >> most melted pistons and a contributor to rod bearing failures. For the
> >> Vanagon it is of significant concerns as due to all the other noise and
> >> design of the engine it is not easily heard when it occurs.
> >>
> >> Dennis
> >>
>