the future of motor oil?

http://physicsweb.org/articles/world/15/2/7

 

Shoving 0W20 down our throats to reduce C02 by millions of tonnes (its
a British story) seems to be the future.

Note that even 5W30 specs are more like 5W25 in actual grade, if there
were such a thing. Also interesting that this story proclaims oil
increases in viscosity with use. B.S., the modifiers break down and
the oil reverts to its true state, which is thin, not thick.

This story is a tree hugger event.

Still sticking with 10W30.

 

Some "abuse" of oil is known to lead to oil thickening.

I know you're making up the "5W25" number, but there are variances
in the acceptable range for an XW-30 oil. The lower limit is 9.3
cSt at 100 °C, while the upper limit is 12.5 cSt at 100 °C. Mobil
1 5W-30 is 10.0, their "conventional" oil is 10.8, while the green
colored Castrol Syntec 0W-30 (AKA "German Castrol") is reported to
be somewhere over 12.

Some manufacturers (esp European) have come up with their own
approval lists or specs that are more than just the standard
(arbitrary) SAE weights. BMW LL-01 spec oil seems to be met
by a number of XW-40 oils, and some 0W-30/5W-30 oils that are
on the heavy end of 30 weight. The SAE scale is a very blunt
tool. An analogy would be that the manufacturer spec'ed a part
that weighs between 130 and 150 pounds, but the suppliers have
adopted a standard measurement of "light" from 120-140 pounds,
and "medium" from 140-160 pounds.

 

Agreed if you cook oil in a turbo and such it can thicken. Abuse was
not the standard set by the cited article, however. In fact, it seems
to set the stage for thinking that one can and probably should use a
lightweight oil, because it will thicken with time anyway. That's not
generally true, but the less informed might buy into it. I just think
this article is "greenie" propaganda. (And I am not painting the
poster, Jim Beam with that brush, it is an interesting article but I
think there is a subtext to it.)

 

What percentage of the film strength of 30 weight oil does your engine
actually require to operate safely?

 

How many foam hits can a shuttle take, before it falls apart on
re-entry? How much radiation can a person suffer before getting
cancer?

Define "safely" -- do you want the car to last 50,000 miles; 100,000,
200,000, what?

We all take various forms of hits all the time, eventually they catch
up to you.

 

If you don't have a clue, why not just say so?

 

subtext? only subtext i can think of is questioning why the brits are
publishing this stuff. what happened to research over here?

 

Oh sh*t, you're on to me. I don't have a clue what all the various
needs of an engine is, but I do know that the amount of allowable
contact, and the possible film strength varies a lot at different
points within the engine. The metal components will vary too, so with
all these variables there's no meaning behind the question that you
asked. There WILL be metal-to-metal contact in the valve train at
times. Also at the top ring/cylinder. And even in crankshaft to
bearings when lugging an engine.

 

No - but the API Sequence tests are purposely designed to thicken
the oil. For most people the shearing down of VI improver is
probably going to be the bigger issue.

 

The more I learn, the more I question the validity of the 20/30/40 wt
method of measurement. Many of the European automakers have their
own standards for cars (incl GM's European division) which aren't
met by the SAE viscosities.

I was at AutoZone buying some filters for a Buick, and was curious
about this "German Castrol" 0W-30 that many VW owners are looking
for. What I saw was an API SL/CF oil with no "Energy Conserving"
mark and no "Starburst". It met a whole slew of European extended-
drain manufacturers' standards from BMW, Mercedes-Benz, VW, etc.
It's not an oil designed for fuel economy, but is technically still
a 0W-30 oil.

I think Honda would be wise to abandon their standard 5W-20
recommendation and come up with their own standard. I think it
would be one that could be met by some thinner 5W-30 or a thicker
5W-20. The oil marketers could simply label that their oil meets
Honda spec X, just like many state GM 4718M or BMW LL-01.

 

Maybe - maybe not. Note the author "Ian Taylor is in the Automotive
Lubricants Group at Shell Global Solutions (UK)" Hey, maybe he's the
marketing geezer. At any rate I'd say it's more likely the lubricants
divisions see new regs/specs as another opportunity to make extra $$...
just like the auto companies finally twigged that catalytic converters,
air-bags, crash safety structures, etc. etc. were all additional markup.

Me too. Let someone else be the guinea pig.

 

I'm still wondering if the SAE viscosity scales are outdated. For
instance, an XW-30 oil is one that has a viscosity of 9.3-12.5 cSt
at 100°C. The typical "energy conserving" 5W-30 is going to be
somewhere in the 10-10.5 range. I've heard from some sources that
certain European carmakers have designed their engines such that
they're most happy with an oil somewhere on the high end of 30
wt to 40 wt oils. I don't think there's a single oil that both
meets the BMW LongLife, or assorted VW standards and **also**
meets the API "Energy Conserving" standard.

I've heard tons about the ACEA A3 extended drain standard. After
looking at what does and doesn't meet the A3 standard, it almost
seems that an XW-30 oil has to be on the high end of the range
to meet said standard. What does meet it are some 0W-30 and 5W-30
oils that are so thick at operating temps that they don't qualify
for the API's "Energy Conserving" standard.

 

Read up:

<http://www.imakenews.com/lng/e_article000388090.cfm?x=b2V1dRQ,0,w>

It's a report on possible alterations to SAE J-300, which is the
current SAE viscosity measurement scale (10W-30, etc). There seems
to be opinions that current SAE viscosity measurement is inadequate
to describe the viscosity needs of modern engines.

--quote--
"While J-300 has been in use many years, it is rigid. Consumers
don't understand it, it's difficult to modify to incorporate
technical advances in high quality base oils, and its awkward
grading system makes it difficult to include the influence of
engine oil viscosity on fuel efficiency," McMillan said.
--unquote--

 

The SAE specs have their good points too - certainly until recently they
did not allow for any overlap at all: you could not sell as 5W-30 as a
10W-30 even if it fit in every other way. I'd hate to think we could end
up with a one-size-fits-all policy here.

Yep, there's always been a dichotomy there - VW used to recommend 20W-50
al-year round not that long ago. I still have my '92 Integra shop manual
which specifies that 5W-30 in a GSR was good only up to a max of 32F
ambient temp. I also don't think you'll find Honda/Acura recommending
5W-20 for the NSX - last time I saw, it was still 10W-30 when 5W-30 was
being used in most of their other cars.

 

If you read the article I linked to, the proposed supplement to the
weight scales included a "triangle" representing additional performance
ratings. These were fuel economy increase (over the reference oil),
HTHS (high temperature high shear) performance, and cold weather
pumping temprature. Of course properly making an oil means trading
off some of that fuel economy for high shear performance (i.e. you've
got to make it thicker).

Well - there have been some who point to the A3 standard as a guide
to whether or not an oil is properly designed for longer drains. The
newer Mobil 1 EP oils in 5W-30/10W-30 still don't meet the ACEA A3
standard. Although they don't carry the "Energy Conserving" label,
I'm guessing that thickening the oil to meet ACEA A3 probably would
have resulted in lower fuel economy.

Doesn't a lot of that have to do with the performance of available
oils at a given time? The European carmakers seem to have gone
through the additional step of publishing their own standards and/
or publishing approval lists. While brand name can't really be
mandated in the US, I see no reason why there couldn't be a list
of "recommended" products.

Even GM is reactivating their low-temperature pumpability standard
(GM 6094M) and apparently recommending that owners use an oil
meeting that standard.

<http://www.imakenews.com/lng/e_article000098055.cfm>

 

Sounds to me like "properly making an oil" is going to lead to extortionate
pricing. Hate to sound cynical but this is all tinkering with specs and
the lube companies appear to be manouvering to position themselves
tactically in the marketing war. The fractions of a mpg which can be
achieved through lubricant tampering are miniscule & irrelevant.

There's no magic here - there are certain materials, basestocks, which are
available and certain additives which help enhance certain performance
aspects. From there, there are limits to what can be achieved. To me this
is all hot air from companies prepping themselves to make additional profit
out of regulations. As usual, first we'll have voluntarily applied new
specs... followed by new regs... probably in the name global warming...
blah... blah... blah. Statistics will be presented which show the "huge
potential benefits" but it's really all BS. I already feel a hand in my
pocket.

 

The cost of making petroleum oils is going up with the cost of crude.
That being said, the price of oils in North America is still quite
reasonable. That $5 quart of Mobil 1 I might buy off the shelf at
Wal-Mart (that meets some European standards) is going to be about
3-4 times more in Europe.

I think one of the reasons why they want to go to this is because
the API specs are starting to become irrelevant for some carmakers.
BMW, VW, Mercedes-Benz and others are saying ignore the API quality
grades and SAE weight scales in favor of their own performance
standards. I'm not an expert, but I've learned enough to realize
that saying an oil is an SAE 5W-30 meeting API SM may not be
adequate for many carmakers. A 5W-30 synthetic oil suitable for
a typical Japanese-designed engine won't be the right choice for
a VW.

The materials are still improving. I researching the stuff in the
lubes publications, Mobil is developing a more advanced PAO
manufacturing process. Hydrocracking is still being improved.

 

Interestingly enough, the improved base stock refining methods which have
been coming on line and continue to do so (GTL, gas-to-liquid, is the next
one coming along) have followed a learning curve similar to electronics.
Not only are the base stocks getting better, they are getting cheaper to
produce.

Have a look at this recent paper internal to ExxonMobil as one example:

http://www2.exxonmobil.com/corporate/files/corporate/campaign05/gtl_nextgeneration.pdf

See page 7 where they say:

"Technology Paradox: Lowest cost process makes highest quality product"


John

 

Do you have accurate pricing data on that? There's no reason that Mobil1
should cost 3-4 times more in Europe, assuming that an exact equivalent is
available there at all. First, if you're thinking Euro gas prices are 3-4x
US price, those are due to extortionate pump taxes, something we narrowly
missed - the crude is basically the same price.

Second, the higher price of Mobil1 in the U.S. vs. petro-based basestock
lubes is due to the cost of producing it: ethlyene has its own world market
driven price (China is sucking it up curently); two separate polymerisation
reactions are required, plus recycling and back-end refining to produce the
PAO mix of decene dimer, trimer and tetramer. IOW the manufacturing costs
swamp the cost of the crude, which has already been through a couple of
refining steps to get to ethylene and those costs would be no higher in
Europe.

You need some slop in the definitions of what a number means in terms of
how the product behaves; lubricants cannot be made to a high level of
precision without incurring disproportionate costs. We also must have
lubricants which cover a range of use conditions - it would be madness to
make and label the "ideal oil" for different classes of engines. I trust
SAE to come up with some improved method of expressing product
suitability/quality more than any group of car mfrs... and without ending
up with highly specific lubricant specs by the car mfr or even engine.

As for VW and a 5W-30, I've no idea what VW is currently recommending but
they have always tended to specify a higher viscosity oil than say Honda...
e.g. a 20W-50 when Honda was on a 10W-30 for a temperate climate. Other
than that it's no big deal.

And most cars still run just fine on good old petro-based, vacuum
distilled, dewaxed basestocks. PAO is about as far as you can go here -
it's the ultimate *reasonable* cost lubricant; if you know of something
better, please tell how it's better - a branched chain paraffin brings the
VI advantage of the paraffin without the wax of a straight chain... that's
about all there is to it. Of course, more recently the SuperSyn PAOs have
allowed VI to be bumped up at the cost of a slight increase in pour-point,
but with the advantage of reduced or zero VI improver additives - a
relatively minor improvement.

While it is probably possible to make PAO molecules which are more tightly
controlled as to their form and characteristics, I doubt that there would
be significant benefits from them... and the closer you get to a single
molecule, the higher the price is going to get. You're also going to have
to deal with the cons which are bound to be present in that single
molecule... or tightly controlled group of molecules. There's a reason,
e.g., that we don't all burn 2,2,4-trimethyl pentane in our SI engines.

While we may, after all, get those "better" PAOs, I don't expect some
quantum leap in performance from them. Funny thing is, that in Europe,
people tend to drive much shorter distances per trip, which means that the
engine oil has to deal with faster and higher pollution by water + the
dissolved contaminants. In the end, it's cheaper to replace the oil than
develop something to handle that abuse. I really don't think there's a big
market for a 15,000mile oil - I certainly wouldn't let oil go that long.

As for hydrocracking being improved, that's how the process industry works
- that's why they employ chemical engineers... to improve yield and quality
with the same basic equipment. In the end, hydrocracking, as applied to
lubricant grade petroleum, is just an attempt to produce something nearly
as good as PAO, without having to start by steam cracking naphtha. They
have to do *something* with what comes out of the bottom of a pipestill -
the more $$ they get for it, all the better for them. If they can get some
govt. wag to slap a sticker on it, even better.... for them.