HE MOST CHALLENGING standard for EP Gear Oils is the US Steel 224 protocol, which
includes the US Steel S-200 oxidation test. Very few oils pass this test.
There are two sets of gear oils above. The samples on the left side of each set
are fresh samples of AMSOIL SGO EP-460 and Mobilgear SHC-460 respectively. The bottles on the
right in each set are the same oils after exposure to the US Steel S-200 oxidation
test (ASTM D-2893). The test measures an oil's ability resist oxidation in high
temperature conditions. After 312 hours of testing at a grueling 250°F, AMSOIL
displayed virtually no signs of oxidation. Mobilgear SHC 460 darkened considerably
and its viscosity increased beyond the ISO-460 range.
The chart on the left shows EP requirements of US Steel 224 and the test results
of AMSOIL SGO ISO-460 and Mobilgear SHC-460. AMSOIL provides superb performance in
all categories. In each category, the higher number represents a superior result.
AMSOIL SGO has Falex loads and weld points that are among the highest available.
The Load Wear Index and the Timken OK Load results also vastly exceed the US Steel
This product is part of our top performance commitment. You can count on AMSOIL
to provide the best products available on the market. Thank you for your continued