API SN Engine Oil Category

In 2010 the American Petroleum Institute introduced a new engine oil category under the name API SN and a new supplemental category called Resource Conserving.

The API SN category is an improvement over the API SM category in the following areas:

This means that API SN compares to API SM like this:

API SN and API SM comparison chart

API SN and API SM comparison chart

The Resource Conserving supplemental category requires further properties. The former supplemental category, which was called Energy Conserving required only fuel saving properties from the oil. Resource Conserving requires further properties like:

The requirements of API SN with the Resource Conserving supplemental category are identical to the requirements of the ILSAC GF-5 standard.

In order for an oil to meet the requirements of API SN or API SN/Resource Conserving it should satisfy the following test criterias:

  API SN API SN + RC
Viscosity Grades 0W20, 0W30, 5W20, 5W30, 10W30 Others Multigrade variations of 0W, 5W and 10W
Laboratory Tests
Sulphur, max %
0Wxx and 5Wxx 0.5 NR 0.5
10W30 0.6 NR 0.6
Others NA NR 0.6
High temperature deposits, max mg
TEOST MHT 35 45 35
TEOST 33C NR NR 0.6
Foam 1 min. settling 10 min. settling 1 min. settling
Gelation Index 12 NR 12
Emulsion Retention NR NR No Water Separation
Seal Compatibility ILSAC GF-5 limits apply
Phosphorous, max% / min% 0.08 / 0.06 NR / 0.06 0.08 / 0.06
Engine Tests
Sequence VID NR NR Pass
ROBO or Sequence IIIGA Pass NR Pass

Source: American Petroleum Institute

Check out our API Engine Oil Categories page for information about further API Oil Standards!

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