First it was Valvoline. In July of 2008, it
claimed the company's SynPower motor oil
provides 4X better wear protection than Mobil
1 in the Sequence IVA wear test. Then Castrol
literally jumped into the game with an
advertising campaign rolled out during the
SuperBowl saying that Castrol EDGE offers 8X
Better Wear Protection Than Mobil 1 in the
same test.
With Valvoline and Castrol making such bold
claims, one of the big questions asked is,
"How much better its Pennzoil Platinum when
compared to Valvoline, Castrol and Mobil 1?
To get answers, JobbersWorld decided to put
this question directly to Shell. Here is what
we found.
According to Selda Gunsel, Manager,
Lubricants Technology Group, Shell Global
Solutions (US) Inc., "Although Pennzoil
Platinum performs exceedingly well in the
Sequence IVA wear test, the battle of the
"Xs" comparing oil against oil rather than
oil against spec is one we are staying out
of." And Gunsel says, the
reason they are is because it's "bad science"
and could be misleading.
To understand what Gunsel means starts with
an understanding of the Sequence IVA wear test.
The Sequence IVA is an engine test designed
to evaluate the performance of engine oils in
preventing camshaft lobe wear in an overhead
camshaft engine. It's a 100-hour test of 100
hourly cycles. When completed, each of the 12
cam lobes in the test engine is measured for
wear at 7 points. An average is calculated
based on the total wear from the 12 cam
lobes. In short, test results with a higher
number means higher wear.
For an engine oil to qualify for API SM/
ILSAC GF-4 rating it must pass the Sequence
IVA with an average wear of 90 micron maximum.
Now for the part about "bad science."
According to Gunsel, "considering that one
standard deviation from the mean in the test
is 12.5, there is no statistically
significant difference for test results
within 35 microns of each other."
Based on data published by Valvoline, whereas
Valvoline SynPower showed an average of 20
microns in the Sequence IVA wear test, Mobil
1 5W-30 averaged 180 microns. If Valvoline's
data is correct, Gunsel says, "This is
certainly a statistically significant
difference." Moreover, it speaks to the basic
pass/fail threshold of 90 microns or less
required to meet SM/GF-4.
But moving beyond the issue of does it or
doesn't it when it comes to Valvoline's claim
about Mobil 1's score in the Sequence IVA,
Troy Chapman, Marketing Management Team
Leader Pennzoil Brands with Shell says the
comparisons move to another level when you
look at the Sequence IVA tests results for
Shell, Valvoline and Castrol in the Sequence
IVA. Troy notes, "you are no longer comparing
a result of 180 microns with 20 microns.
Instead, the comparison is being made between
three brands each with less than 20 microns
of wear in the test." This moves the
comparison into and area where differences
are "statistically indistinguishable."
(See Graphic
that follows)
Chapman adds, "This is why it would be bad
science for Shell to add its bar to a chart,
or say X times better when comparing Pennzoil
Platinum with Mobil 1, SynPower and Castrol
EDGE." Not because their average in the
Sequence IVA (which Gunsel says is less than
20 microns) would not comparable very
favorably with what Valvoline claims is Mobil
1's average. "Instead," Troy says, "it's
because consumers may get the message that
the comparison is also between Pennzoil
Platinum, SynPower, and Castrol EDGE. And
that would be a mistake." First, it would be
misleading since there is no statistical
difference for test results below 35 in
Sequence IVA. Secondly, by spending time with
statistically insignificant and misleading
comparison, consumers may lose focus on such
issues as cleanliness and others where there
are true performance differences in engine oils.