[W126 Coupe] don't use high mileage oils

Thu Jan 27 01:40:31 EST 2005

I do not represent either of these companies. I generally recommend Mobil to anyone without details( I'm worn out) since it is the most generally available. I am a water treater and lubrication engineer for over 20 years each for industrial applications. My company has a great crankcase oil which I will not mention or promote primarily because it is not readily available and all the talk just to sell a case. I would rather sell drums of high temp chain oil at $2400/drum and not have to argue my points. I know no more. Regards, Jim A.

-----Original Message-----
From: "Shayegan, Richard" <rishayegan at davidson.edu>
Sent: Jan 26, 2005 6:49 AM
To: Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>
Subject: RE: [W126 Coupe] don't use high mileage oils

Jim, you sure about that 0w-40 is the same as straight 40? The way I
understood it is that if a number is followed by a w, that means that
the number is the viscosity rating at the SAE low temp mark (forget what
that is, I think -40F...or is it C) and then if a number isn't followed
by w it is the viscosity at the high temp mark (again, forget what that
is). So basically, my understanding is that 0w-40 is 0 weight when cold
and 40 when hot, and that straight 40 doesn't meet the cold weather mark
at all (which is why there is no w). Is this wrong? As far as Castrol
Syntec, after seeing the inside of my engine that never had the same oil
in it for more than 4000 miles, usually 3000, and 90% of the time that
oil was castrol gtx, I'm turned off to Castrol. However, that ford
mechanic friend I was talking about, who also builds funny cars (in the
plural) says he really likes syntec. When I said Mobil 1 v Amsoil, he
said Mobil 1 is hard to beat and he's thinking Mobil 1, but at that
point you're splitting hairs. I still don't know, Mobil 1 or Amsoil.
Mobil 1 gets such a strong recommendation from the car guys on the net,
but the fact that all the hotrod hicks I know use Amsoil makes me want
to try Amsoil. I got a month to think about it I guess.
Richard

-----Original Message-----
From: mbcoupes-bounces at mbcoupes.com
[mailto:mbcoupes-bounces at mbcoupes.com] On Behalf Of jralex at ix.netcom.com
Sent: Wednesday, January 26, 2005 3:59 AM
To: Mercedes Coupes Mailing Lists
Subject: Re: [W126 Coupe] don't use high mileage oils

The oil numbers refer to viscosites. 15W 50 means that the oil behaves
like a 15 weight when cold and a polymer pulls in the characteristics of
a 50 weight when engine gets hot. So, 0W 40 is actually a straight SAE
40wt. without winter characteristics. Actually the 15W50 is better for
winter but of all the superior qualities of a sysnthetic which is
polyalphaolefin with a kiss of polyolester and diester. The later two
are used to get the addditive package into the matrix and are nonlinear.
PAO is linear and therefore able to mix with any mineral based oils left
in the system. The quality of a syn. to not get thick over night which
make petro based flow slowly on initial start up on a cold morning is
enough reason to use it. Most wear occurs as a condition known as
'boundary condition' i.e., tne oil is not present as opposed to full
film or 'elastohydrodynamic lubrication'. For the same reason you guys
kill the coil after oil change synthetics get to the moving parts
faster. Satish put a syn. and a dino quart in his freezer overnight and
pored each into a paper cup. After observing the flow rate differance He
said it was no contest. That without question He would  use Syn.
especially winter in Detroit. Syn. is 30 times less volitile that dino
meaning the syn does not evaporate leaving sludge components. It is far
more resistant  to oxydation and chemical attack. Need I say more! Major
oil companies are always looking for another category other than 'Me
Too' so as to capture market share for profit. All majors have
synthetics but fought it for years. Castrol started using a Group IV
highly refined petroleum base stock calling it synthetic argueing that
the process qualified it as synthetic. Mobile took them to court and the
decision favored Castrol! The industry is in an uproar over this court
crap. It is deceitful in that all know that synthetics have always meant
PAO!! Enough! Richard, by the way if you go to Mobile 1, a good choice,
and extend your drain intervals to 3 or 4 times as long at least DO
change your oil fiter every 3K and add a little for filter loss. I have
run out of typing ink. Later, Jim Alexander
-----Original Message-----
From: "Shayegan, Richard" <rishayegan at davidson.edu>
Sent: Jan 25, 2005 3:16 PM
To: Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>
Subject: [W126 Coupe] don't use high mileage oil
I e-mailed Pat Goss just to see what his thoughts were on going to a
thicker oil as a car ages. He said that he doesn't think it's a great
idea, and in fact he likes Benz's new recommendation for older cars too
(namely, 0w-40 synthetic). I asked him if he knew of a regular oil that
was 0-40 since I have a leaky rear main seal and don't fancy the idea of
synthetic all over my driveway. I mentioned that the rear main seal had
pretty much fixed itself after 2 years of high mileage oils though. Then
he told me that now that I've used high mileage oils, I have no choice,
I have to keep using them. He said unless an engine is in serious need
of seal swelling, don't do it, because it overswells the seals and then
the car becomes dependant on that extra swelling. He said I might be
able to still use regular oil since I'd only used the high mileage for
15,000 miles, but that even though it's only been 15,000 miles I may
still experience oil consumption if I go back to regular oil. I don't
know about y'all, but I hate the idea of being dependant on an oil,
especially one that only comes in 2 acceptable weights, so I thought I'd
give y'all a heads up.
Richard

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