So, the test vehicles were torn down at 60,000 miles?  I have a feeling that
that is too short a test.  You repeated the testers comments that the
synthetics flowed better at low temperatures and provided better protection
at high temperatures. That news alone is a good recommendation to use
synthetics.   I live in Minnesota where the low can be -40f and the high can
be +95f from season to season.  Also, the aircraft industry uses synthetics.
If you want an example that absolutely requires the best protection ... Well
I don't often get my '82 to 30,000 feet, but I would just as soon my engine
lasted as long as possible.

The fact that the oil changes were performed at reasonable intervals that
were shorter than those  recommended by the industry weakens the test in the
area of oil characteristics in hard service.  There are a lot of folks who
rarely change their oil.  As tough as taxi service may seem, it's nothing
compared to a teenager on a limited budget, or a high mileage salesman who
doesn't care much because he's gonna trade in the car every two years.  The
use of fleet vehicles that are professionally maintained and have regular PM
intervals invalidates the oil performance test.

I'm guessing that when there is a test that goes over the 100,000 mile mark,
or a maximum - possible mileage test, where the oil is changed every 7000 to
10000 miles, there may be discernible differences in the inspections of the
engines.  60,000 is a VERY young engine.  In my opinion, the referenced test
was prematurely ended, the oil change intervals too short, and the results
are therefor no more useful than anecdotal evidence.
Respectfully,
Steve

-----Original Message-----
From: The Henrys <jch@VNET.NET>
To: vanagon@GERRY.VANAGON.COM <vanagon@GERRY.VANAGON.COM>
Date: Thursday, March 25, 1999 8:31 PM
Subject: Re: Synthetic oil not worth it (long)

>Hello all
>
...snip...
>One distinction: According to the laboratory tests, Mobil 1 and Pennzoil
>Performax synthetics flow better at low temperatures. They also have
>the highest viscosity under high-temperature, high-stress conditions,
>when a thick oil protects the engine. Thus, the article suggested that
these
>oils may be a good choice for hard driving in extreme temperatures.
...snip...