AMSOIL
10W-30 Excels in API Sequence IIIF Test
The
Sequence IIIF test is a stringent API SL, ILSAC GF-3 test designed to measure
oil thickening and piston deposits in high temperature service, as well as provide
information on valve train wear. The test is designed to emulate high-speed service
under high ambient conditions.
OBJECTIVE
Subject AMSOIL 10W-30
Synthetic Motor Oil (ATM) to an independent API Sequence IIIF Test to determine
its effectiveness in preventing deposit formation and providing wear protection
in high temperature conditions.
SPECIAL CONDITIONS
Because
AMSOIL is formulated to provide superior performance over extended drain intervals,
testing was allowed to continue for 240 straight hours, three times the length
of the standard Sequence IIIF test.
TEST PROCEDURE
Testing
is conducted with a 1996 model Buick 3800 Series II, water-cooled, four-cycle,
V-6 engine. The test engine is an overhead valve design (OHV) with a single camshaft
operating the intake and exhaust valves through pushrods and hydraulic valve lifters
in a slider-follower arrangement, and it has one intake and one exhaust valve
per cylinder. Induction is performed through a modified GM port fuel injection
system with the air-to-fuel ratio set to 15:1.
Running unleaded gasoline,
testing begins with a 10-minute initial oil leveling procedure before slowly working
its way up to test speed, temperature and load conditions. Testing continues at
100 bhp, 3600 rpm and 155° C oil temperature for 80 hours with oil checks performed
every 10 hours. Kinematic viscosity increase and wear metals (Cu, Pb and Fe) are
evaluated at every 10-hour interval.
At the end of 80 hours, all six pistons
are inspected for deposits and varnish, camshaft and lifters are measured for
wear and oil screen plugging is evaluated.
| Sequence
IIIFTest Parameters | AMSOIL 10W-30 (ATM)Triple Length
(240 hr.) | API SL Limits(80 hr.) |
| Kinematic
Viscosity, % Increase at 40° C | 90.42
| 275
max. |
| Weighted Piston
Deposit Rating | 4.51 | 4.0 min. |
Average
Piston Skirt Varnish Rating
| 9.50 | 9.0
min. |
| Cam Plus Lifter
Wear Average µm | 11.8 | 20 max.
|
| Hot
Stuck Rings | 0 | None |

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TEST
RESULTS
Even at three times the standard test length, AMSOIL 10W-30 performed
three times better than the test limit in the area of kinematic viscosity increase,
and it excelled in all areas of the test. AMSOIL 10W-30 Motor Oil kept viscosity
increase, wear, deposits and varnish to a minimum. The pictures below demonstrate
the superior protection provided by AMSOIL Motor Oil throughout 240 straight hours
of Sequence IIIF testing.
While conventional motor oils tend to thicken
and lose their lubricating effectiveness, AMSOIL Motor Oils are formulated to
maintain their viscosities over extended drain intervals. The results of the Sequence
IIIF test clearly demonstrate the long drain capability of AMSOIL 10W-30 Motor
Oil. Even after being subjected to a triple length Sequence IIIF test, AMSOIL
10W-30 performed three times better than the standard test limits. The competitor's
motor oil shows dramatic viscosity increase in less than half the time.
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greatest overall load concentration and stress are placed on the piston skirts
and rings on the thrust sides of the pistons as they move down, contributing to
heavier deposits than the anti-thrust sides. Even after being subjected to the
Sequence IIIF test for three times the standard test length, the pistons (above)
lubricated by AMSOIL 10W-30 Motor Oil show minimal deposits and varnish. In fact,
upon close inspection, the original piston machine markings are still visible
on both sides of the pistons. This superior protection provided by AMSOIL Motor
Oils extends the lives of both old and new vehicles, even in severe driving conditions. |
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| Even
at three times the standard Sequence IIIF test length, the oil pan, screen and
valves showed no signs of deposits, oxidation or plugging. By keeping engines
clean and deposit-free, AMSOIL Motor Oils effectively reduce wear and keep engines
running smoothly for extended drain intervals. |
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