FUELS & LUBES INTERNATIONAL
Quarter Three 2014
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(ILSAC) for a new grade with a lower high-
temperature, high-shear-rate viscosity than
SAE 20. Before the ink was dry on SAE 16,
Honda contacted the SAE Engine Oil Viscos-
ity Classification (EOVC) task force to define
up to three additional lower-viscosity grades
to provide the framework for upcoming
fuel-efficient vehicle platforms. Rheological
limits of kinematic viscosity and high-tem-
perature, high-shear-rate viscosity are cur-
rently under discussion within the EOVC.
Although they have not been defined yet, any
new grades endorsed by SAE will be under
the ILSAC GF-6B engine oil performance
category, which will be available no earlier
than January 2017.
Brown emphasized that J300 sets the
standard for viscosity grades. He emphasized
that it is the job of OEMs to build engines
that can accommodate lower-viscosity oils.
Advancements in the roller followers, bear-
ings, piston rings and surface roughness will
need to be made to create effective low-fric-
tion engines. Lower-viscosity grades will also
need effective additive technology to work.
Additives generally make up 15% to 25% of
passenger car engine oils and usually include
a detergent inhibitor package, a viscosity
modifier and a pour point depressant. The
use of friction modifiers has helped reduce
the friction coefficient in elastohydrodynamic
(EHL) and boundary lubrication regimes.
“The work that is being done to extend J300
to lighter-viscosity grades is really a hydro-
dynamic lubrication project,” Brown said.
“But it does affect what goes on in these other
regions,” he said, referring to the mixed lubri-
cation, EHL and boundary regimes.
Guinther spoke about tests that Afton
Chemical has performed to measure the
durability and fuel economy of 0W-16 oils.
A series of API tests included Sequence IIIG
for durability, Sequence VG for deposits and
Sequence IVA for engine wear. Ultimately
it was found that lower viscosity has no ef-
fect on these areas. “All this is good news,”
Guinther said. However, he pointed out that
the sequence tests are only starting points
and may not reflect the everyday uses of the
engine and the oil. Guinther then discussed
the Afton Continuous Aging Fuel Economy
(A-CAFE) test he helped develop. The test
was run on a 2012 Chevy Malibu with a LY7
V6 engine using three oils: 5W-30, 5W-20
and 0W-16. It turned out that the engine was
able to discriminate viscosity without dura-
bility issues. A directional increase in fuel
economy was found: the 5W-20 oil did 1.3%
better than the 5W-30 oil, and the 0W-16 oil
did 0.3% better than the 5W-20 oil.
Afton Chemical conducted the same test
on a 2012 Honda Accord with the purpose
of finding the tipping point at which low
viscosity causes an increase in fuel consump-
F E A T U R E
From left to right: Ken Chao, Greg Guinther, John Cruz, Masashi Maruyama, Mike Brown
tion. The test oils included a baseline similar
to SAE 5W-20 and three test oils that were
progressively lower than that in kinematic
and HTHS viscosity. The test included the
European ARTEMIS driving cycle, which
averages around normal U.S. driving speeds
but also includes some high-speed driving,
putting more stress on the Accord’s I-4 en-
gine. It was found that the best fuel economy
was achieved with the baseline oil. After that
tipping point, the lower-viscosity engine oils
caused higher fuel consumption.
As Guinther said, “Context is everything.”
The aforementioned test on the Chevy
Malibu, which involved a more lightly loaded
engine, did not show this increase in fuel
consumption. The Malibu was able to re-
spond to lower-viscosity oils without straying
into mixed or boundary regimes. Engines put
under real-world stress show less apprecia-
tion for low-viscosity oils.
The third speaker, Cruz, spoke about the
new oil category that is being developed, PC-
11, requested in 2011 by the Engine Manu-
facturers Association (EMA). The category
is scheduled to go through a test matrix in
May 2014 and is projected to be available to
the market in 2016. When PC-11 oils become
available, nearly 10 years will have passed
since the introduction of a new heavy-duty
diesel engine oil category.
The main EMA propositions for PC-11
are improved fuel economy and oxidation
control, as well as maintaining the attributes
of the current oil category, API CJ-4. There
are two types of PC-11 oils being developed,
categories A and B. PC-11A is fully backward
compatible, designed for on- and off-highway
use. PC-11B is for highway use only. PC-11B’s
limits on HTHS viscosity are between 2.9
