Date:         Sat, 13 Feb 93 06:40:32 GMT
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         behanna@syl.nj.nec.com (Chris BeHanna)
Subject:      REPOST: Comprehensive Oil Article (Was: Re: Synthetic oils: better than, say, Castrol GTX?

dylan@cs.washington.edu (Dylan McNamee) writes:
>Addressing the original question, which is better, Castrol GTX changed
>every 3,000 miles, or a synthetic oil changed at 3,000 or 5,000, or
>7,000? When it comes down to it, the extra cost (about $7/4 quarts
>vs $16/4 quarts) would be worth it, if there was a difference.

 If you're operating under *severe* conditions, e.g., racing, then
it might be worth it.  All that I have heard from people who have torn
down motors beyond 80K is that if you change the oil and filter every 3K,
then the crosshatch from the original factory cylinder honing will still
be visible in the cylinder bores.  Sounds like dead dinosaurs do the job
just fine.

>I must have missed the "conclusive" report posted earlier, so maybe it's
>time for a repost, or at least a followup discussion.

 It is included at the end of this article.

>One more question;  has anyone tried Kendall Oils?  My father swears by
>them, claiming the other brands spend their money (and hence your cost)
>on advertising, whereas Kendall oil is just higher quality.

 From what I understand, Castrol uses the best additive package
of all dead dinosaur oils, so that's what I use.  Kendall is commonly
used by dealership service departments, which I don't trust to do anything
except maximize their profit, so I don't respect their choice of oil.
That, of course, is nothing but my own personal bias and should be
taken or discarded as such.

----------------------------------------------------------------------
Some additional notes
=====================
The following notes are derived from a posting by
mvs@mink.att.com (michael.a.van stolk).

SWITCH OVER:
============
By the way when you add synthetics to an "old" engine, it will spend the
1st 5-15K removing the old gunk. This is why YOU MUST change the oil
filter regularly at first, it gunks up with your engine dirt. (80K miles
on a car, change oil filter at 83K, 86k, 90K, etc...). Also your engine
may start dripping on the floor. Don't blame the synthetic.
It will do this because the wax is being removed from the inside of
the engine and the seals are dry from not having been exposed to oil
to keep them fresh for a long time. As the new oil reaches the gaskets
and seals, they will expand to fill the cracks.

COST:
=====
It is cheaper than regular oil. I used to change my car oil every
2000 miles incl filter (5*$1.25 + $3.00 = 9.25 every 2000 miles.
Now I change it every 6000 miles (5*$3.25(kmart price) + $3.00) = 19.25
for 6000 miles. 19.25 for synthetic for 6Kmiles versus $27.50 regular.
You may not like my numbers, but the oil costs are K-mart retail.
Please use a QUALITY 2-STAGE filter which will bypass the oil should it
gunk up in the future(shame on you).

[NOTE: Castrol recommends retaining the original manufacturers
interval, even with synthetic oils. jhv]

OIL PRESSURE:
=============
Your oil presure may drop once you add it. This is ok since oil pressure
measures how much oil IS NOT GETTING TO YOUR ENGINE PARTS. What you want
is the oil to flow between the mating surfaces and lubricate properly.
A typical drop in 5-10lbs is ok with no negative effects.
(This one will take a while to accept, I know)

[NOTE: That may be part of the cause, personally I contribute it to the
lower viscosity or better pourability of synthetic oils.   jhv]
----------------------------------------------------------------------
Subject: Re: [W] G60 30k service Qs

christos@wucs1.wustl.edu (Christos Papadopoulos) writes:
>jtong73@ursa.calvin.edu (Peter Tong) writes:
>>I just want to second what Jan says about 5w50 syntech.  It definitely is
>>the best oil I have run.  I have had it in my 2.0 for over 2500 miles and
>>it is still not dark but looks just like how it looked when I poured
>>it in - with the exception that it is a slight bit browner.
>>There has been no consumption at all on my car either - mileage has
>>been good, and I bet part of it has been due to this oil.
>
>	Ok, Peter (and Jan, and anyone else using Syntec) can you be a little
>more specific on why you liked the Syntec so much? Any opinions are
>welcome, subjective or otherwise.

It's probably more than subjective because it was quite noticable in my
G60: When you start in the morning with a cold engine, the engine
"feels" warmed up, less "sluggish" when you accelerate.
In fact, there is little difference between a warm or a cold engine
in the way it responds, except which can be contributed to a cold fuel
system (5th inj, air cold ==> inefficient air fuel mix/freezing).

When warm, the car feels peppier as well, easier to get up to speed.

Some have reported that the car slows down less when you take your
foot off the gas. I did not notice anything like that though.

>I mean the fact that it doesn't get black would also be a minus (less
>effective detergent package), and little or no oil consumption could
>mean that it's too thick to pass through valves and rings (thus less
>lubrication?)

It will turn rather dark after a while, but it seems to take longer.
Also the reduced consumption may have been purely coincidental with
my engine finally being worn in after 30k miles....
However, others have reported similar effects with (other) synthetics
in older engines.

I am not sure what all this means, less break down, better sealing for
the rings, less detergents? And I don't think this stuff is too thick,
it's about as fluid as water (vs thick maple sirup for regular oils),
which did make me a bit worried. I am most worried about the G60
bearing... the G60 spins really fast and it uses engine oil pressure
for lubrication. Whether it is really protecting the engine better,
naturally I cannot tell you, I have not done an analysis of the oil.

However, my friend in Europe who races his very expensive 944 Turbo "S"
only uses Castrol Syntec (called "RS" over there), same as the other
members of his Porsche club. So I figured, it can't be too bad.
With Synthetics, I almost feel comfortable changing the oil at the
recommended interval of 7500 miles (which is what Castrol themselves
recommended for "normal" duty!)
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