Re: synthetics (long)

[Sargent Schutt <sargent@novagate.com>]

'John Graham' wrote:

   >Great the dirt  or varnish is on the engine not in the oil.Thats some go oil your
   >useing. It plugs up things fast.

I've been told by many mechanics that Valvoline 20w-50 Racing (dino) is good
oil. According to my dealer, Hoehn Audi, it is what VAG specs for our cars. I
change it at 3k mile intervals. So it would seem to be good oil, and good
practice. It has taken about 20k miles to go from consumption (under synth) back to
almost no consumption.

   >> That the synth removes the reg oil varnish means that it is loosening up the
   >> tolerances in the engine. More play between parts means more wear. That's
   >>the physics.

   >Valve gear yes, piston rings and cylinders no.Varnish has never been a good
   >antiwear additive.

Really? I add varnish with every other oil change. Minwax High-Gloss is best.
But seriously, the buildup over time becomes a hardened product that, while not
the slickest surface, whence removed allows for higher level of thrashing vis a
vis increased (out of spec) tolerances. Imagine if I held your head in my hands,
at the ears, and proceeded to shake it back and forth rapidly. Now imagine I held
my hands a *couple inches from your ears* and proceeded to smack it back and
forth rapidly. Which would you prefer? See the parallel here? Removing the
varnish and cleaning out the gunk allows for increased thrashing. THEREFORE
INCREASED WEAR. That's why changing over to synth on high mileage motors
which have an amount of wear and an amount of buildup can even cause lifter
noise, where previous to the changeover there was no noise, and no oil
consumption.  BTDT, seen it, heard it. This isn't fiction, John.

   >> You would seem to have it that it is better to have play in your
   >> internal engine parts and run synth oil than it is to have no slop and no
   >> consumption while using clean regular oil.

   >That something you made up all on your own.

No, it's what happens when the varnish and dino deposits are removed. Fine, I
made it all up. There is no increased play in the internal parts. The oil is just
magically making its way into the combustion chamber. It's all Sigfreid and Roy, pure,
marvelous Vegas entertainment. Now please debunk this incredulous myth
for me, if you will.

   >> I can't agree with that. I see no logic that would support the argument that a
   >> loose motor with synth oil consumption is a good thing compared with a
   >>tighter
   >> motor with no oil consumption on reg oil. I'm not arguing the proerties of
   >> synthetics here, except in as much as I don't believe that a synthetic is good
   >> enough to make up for the play and looseness it causes by a changeover at
   >>high
   >> miles.
   >>

   >If you can't agree with it, then why did you make it up?
   >Know one has said anything like that.

Why don't I agree with something I made up? Huh?. hmmm...

Well, riddle me this:

If my motor is consuming a quart every 3-4k miles, but has no external leaks
and runs at normal operating temps, where has that oil gone? Is there a black
hole in my oil pan? There's some good sci-fi.

I am using appropriate weight oil, and again, my car is running within normal
operating temp range. Therefore it is highly doubtful that I am 'evaporating' that much
oil from within the system (1qt pre 3-4 k miles). Rather, that oil is
making its way into the combustion chamber through newly opened routes,
whereupon it is burned.

Back to the head smacking. How do you NOT have *INCREASED* wear with looser
(way beyond spec) tolerances, particularly in the valve train, but also in the
rings/walls and crank dept? Is synth magic?? I know of no physics which
explain how higher, out of spec tolerances lend themselves to decreased wear
thereafter.  No matter what type oil you use. Smack your head a few times.
Maybe it'll come to you.

Ahh, but it is all such fiction, eh? Fine, John, *explain* where and why my
assertions are such pure, brazen hogwash. I did not enter into this dialogue with
the intent of endurance-testing yet another Nomex suit. Just looking for a
definitive explanation to this phenomenon that occurs during the changeover
from dino to synth on high-mileage motors.  This would seem to be an important
issue, as I and many others buy high-mileage vehicles, and, wanting to do what's best
for them would like to know whether dino or synth is a superior choice.
Especially given the likely wear which has already taken place under the care, or lack
thereof, under the previous owner.

Does the synth eventually build up its own deposits and shore up the leaks it
caused during the changeover? Or does it continue to result in higher oil
consumption? If the oil consumption continues, the tolerances are still loose,
is synth superior? HOW is that possible? And how does the story end with synth
long after the changeover (say 20k miles)? I've not stuck with it long enough to
find out. There are a few issues here. I am hoping for a reasonable explanation of
synth behavior after the changeover to support the contention that it is a
superior solution to dino on high-mileage, gummed up motors, particularly
concerning engine internals (valve train, crank case, rings/walls).

While this thread has certainly been hashed and rehashed, I've yet to see this
particular element (changeover effects) of it discussed to the point of
conclusion. I will gladly take this off-line, indeed I thought I had. Seems there
are still several people interested, though. My apologies to the rest for my
voracious appetite for wordy BW.

And TIA for a good *explanation*.  Certainly I have invited a fiery response here, so
have fun.....

Regards,

Sarge

91 200q 168k miles TAP, etc
86 5ktq 128k miles, IA, etc