Date: Sun, 31 Mar 2002 08:17:37 -0800
Reply-To: Michael Snow <mwsnow@COX.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Michael Snow <mwsnow@COX.NET>
Subject: Re: Synthetic Oil
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Stan Wilder wrote:
> I recently rounded up a nice selection of new unopened NAPA parts that I
> never installed on previous cars I owned and struck a deal with the local
> NAPA to trade them for parts for my current vehicles.
> The exchange went off OK but all the vehicles I own is running great so I
> didn't actually need any parts.
> I settled on several sets of spark plugs etc etc and two cases of 15/50
> Mobil One synthetic oil.
> My new engine has 5K on it and I'm satisfied that its not going to blow
> up anytime soon.
> I'm considering going to the synthetic oil but I like taking a look at my
> oil more often that once or twice a year. Considering changes at 6k
> rather than the normal 3k.
> I understand that once you go to Synthetic oil there is no going back,
> based on general opinion that the engine sets itself for the synthetic in
> some subtle ways. Which I'm not fully advised about.
Stan, let me preface this by saying that I have never owned an air
cooled VW (but I'm thinking about it). I have used Mobil 1 oil in a
variety of vehicles since 1985. It is the only oil I will put in a
gasoline engine.
> I'd like to separate the fact from the fiction:
> #1. Synthetics run cooler ?
> #2. They have less thermal breakdown that dyno oils?
> #3. They handle the heat of Air Cooled better than dyno oils.?
The oil temperature will stay the same. Synthetic oil is much more
resistant to thermal breakdown thatn dyno oils. In this respect they
should handle the heat of your air cooled engine much better than dyno
oils. I put 65K miles on a new Honda Civic using only Mobil 1. I drove
that car like I was trying escape the earth's gravitational field most
of the time. When I sold the car, the inside of the engine had NO
visible sludge or baked on oil.
> #4. You can't go back to dyno oils after you've run your engine on
> synthetics ?
> #5. Oil change intervals are at 6K rather than 3K?
> #6. Can I still run my quart of Marvel Mystery oil for 500 miles before
> oil changes?
There is at least some evidence that you should not begin to use
synthetic oil in a high mileage engine that has been run on dyno oil.
The detergents in synthetic oils can cause large chunks of cooked dyno
oil to break loose inside the engine, possible clogging the oil pump
pickup. I am hesitant to recommend extended drain intervals without
including oil analysis into the maintenance program. In my experience,
and engine run on synthetic oil since the initial break in (on dyno oil)
will be so clean that you will no longer need to use MMO or any other
cleaner.
> #7. Are synthetics more prone to leak than dyno oils?
> #8. Are the current version of oil seals, O rings compatible with
> synthetic oils?
> #9. If the engine sets itself in some subtle way to require synthetics
> after its been run on them ,,,,,,, what are these changes?
> #10. In an emergency, (like blowing lots of oil) can I add a quart of
> dyno oil to the pan without engine damage or ruining the lubrication
> qualities of the existing synthetic oil.?
> #11. If I went back to dyno oils after, say 30K, what could I expect?
> If you've got anything to add that I haven't addressed here, I'd like to
> hear it.
In the early days of synthetic oils, there were many reports of leaking
seals and gaskets. My wife's Honda just turned over 100K miles, and I
have not yet seen not a single drop of oil or even seepage at the seals.
All current seal materials are compatible with synthetic oils. If the
engine does wear in a different way on synthetics, I am unaware of it.
You can always switch to dyno oil without problems. Even with the
advances in oil and oil seal technology, I would be hesitant to switch
from dyno to synthetic oil in a high mileage engine.
IMHO, synthetic oils are THE way to go for a new engine. When I
purchased the wife's Honda in 1997, I added up the cost of oil changes
over a 100K mile period using Mobil 1 vs. premium quality dyno oil. The
synthetic cost about $600 more over 100K miles using the same drain
interval (7500 miles). Cheap insurance if you ask me. A friend of mine
say often that "oil is cheap, engines are expensive". Words for the
wise :-)
Mike Snow
