There are many variable that can affect the condition of oil. Do you run the
engine during those nonuse periods? If so, for how long? Driven at all or
just idling? Is the garage temperature controlled? All these things have an
impact. Some folks think it is good to start the engine on some periodic
basis and let it idle. This will load the oil with some unburned fuel and a
lot of condensation. Storage with temperature swings can also cause a
problem. I have even seen transmissions fill with water, once in my garage!
With today's oils I see no problem going for a year or even longer if the
mileage and other conditions support it. Oil does not go bad in a year just
from sitting. As for condensation that long highway run will clear it just
as well as fresh oil. If the oil is really getting cloudy you need to have
the oil tested to find if it is condensation or a coolant leak. Coolant in
the oil even in small amounts will ruin bearings and cause other damage.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Ellen in Oregon
Sent: Sunday, December 9, 2012 4:13 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Oil change intervals, miles vs. time

Have been following the oil change threads avidly, but now my question is,
for a van that is used for camping only, spending many weeks sometimes
months in garage between trips, what is the interval recommended for that?
On the camping trips, as they are generally quite far, the engine is
well-warmed.  I check oil before every trip, adding if the reading is below
the lower mark.  If I think the oil looks cloudy, I go ahead and change it.
But would be nice to know if there is a specific recommendation for this.
Thank you,
EllenLola, '85 Vanagon ASI camper conversion

'Be Content with what you have; rejoice in the way things are. When you
realize there is nothing lacking, the whole world belongs to you.' ~Lao Tzu