The oxidation makes sense, and of course, you know your stuff.  One
question regarding the oxidation:  If we are talking about winter storage
(the original question), for most owners, that would be at a low
temperature.  Would that make a difference in the degree of degradation?
Reaction rates generally depend on temperature, the higher the faster.
mcneely

On Mon, Oct 11, 2021 at 9:37 AM Steve Bonde <seb007@live.com> wrote:

> From a petroleum chemist’s perspective, mineral oils (non-synthetic) will
> oxidize when just sitting in the engine. That oxidization will form, among
> other things, organic acids that can reduce the engine’s lifetime. I worked
> on a project with the Air Force where we looked at the storage stability of
> their fuels and lubricants. We made recommendations that they don’t allow
> fuels to be stored too long and lubricants be periodically changed.
>
> That said, I only use synthetic due to the chemical makeup, and change it
> every 6 month or 10K miles, whichever comes first.
>
> Sent from my iPhone
>
> > On Oct 11, 2021, at 8:34 AM, Eric Caron <ericcaron96@comcast.net> wrote:
> >
> > Yes,
> >
> >        Great discussion!
> >
> >        There is often more then one right answer to a question.  And we
> get to make our choices based on info given and our own thoughts and needs.
> >
> >        A couple years ago a friend gave me several things from a garage
> full of hoarded items.  I was handed several cases of oil from way back in
> the time when made in round cans.  Even a metal opener with spout.
> >
> > I asked this list and did research and found the oil was as good as it
> was when new.  As good as the standard of the day.
> >
> > I gave it to several VW friends running air cooled and I think one
> vanagon.  It was 20/50 grade.
> >
> > It  was happily put to it’s original purpose with no ill effects.
> >
> >        The oil was good because it had not been opened.
> >
> > Call me silly but I usually change the oil depending on the miles when
> ever that is.  But, If I have the option I do change it in the spring after
> storage.  It just feels nice to start the season with known clean oil.
> >
> > Eric Caron
> >
> >
> >
> >
> >> On Oct 11, 2021, at 8:42 AM, Jim. Felder <jim.felder@GMAIL.COM> wrote:
> >>
> >> Ergo is you change oil before storage in winter, there is no reason to
> >> change it again when it comes spring driving time. I think that issue
> was
> >> at the heart of this thread, so I wasn’t picking your thread apart. I am
> >> just trying to cut through the mysticism and find out if oil goes bad
> >> sitting over a winter. On the two counts you and I have discussed, I’d
> say
> >> it does not.
> >>
> >> Say, this list still has some life in it! This discussion takes me back
> 20
> >> years.
> >>
> >> Jim
> >>
> >>> On Sun, Oct 10, 2021 at 9:48 PM Geoffrey Toye <geoffreytoye@gmail.com>
> >>> wrote:
> >>>
> >>> Yes, if you change the oil before storage then there will be no blowby
> gas
> >>> during storage.  If you don't, then the old oil will have seen lots of
> >>> blowby gas before storage.
> >>>
> >>> Yes, oil cans don't have an expiration date. The antioxidants are
> consumed
> >>> by an operating engine.
> >>>
> >>>> On Sun, Oct 10, 2021 at 5:43 PM Jim Felder <jim.felder@gmail.com>
> wrote:
> >>>
> >>>>
> >>>>
> >>>> Sent from my iPhone
> >>>>
> >>>>> In response to David’s welcome and detailed analysis of acidity,
> water
> >>>> gets
> >>>>> into the oil system by way of the blow by gasses that pass the piston
> >>>> rings.
> >>>>
> >>>> So, if the car isn’t being driven during storage there can be no
> blowby.
> >>>> Hence no water in the oil. So scratch that reason, right?
> >>>>>
> >>>>> Oil contains anti oxidants that are life limited. Old oil cannot
> protect
> >>>>> your engine.
> >>>>
> >>>> I have never seen an expiration date on a can of oil. So scratch that
> >>>> reason as well.
> >>>>
> >>>> I could be wrong of course but I can’t see these so-called threats
> being
> >>>> realized.
> >>>>
> >>>> Jim
> >>>>>
> >>>>>>>
> >>>>>>
> >>>>
> >>>
>