A new mobile natural gas engine oil performance specification has been introduced for stoichiometric combustion Cummins Westport mid-range and heavy-duty engines. This new specification, referred to as Cummins Engineering Standard (CES) 20092, will provide significantly improved oxidation and thermal stability compared to previous natural gas oils. Cummins Westport (CWI) natural gas engines require specially formulated natural gas engine oil, which has different properties than most diesel engine oil. In addition to the new CES 20092, there are two natural gas engine oil specifications for use with CWI engines: CES 20074 oils, which are recommended for lean burn engines and CES 20085 oils, which are allowed but not recommended, for engines using stoichiometric combustion. Please click on the following links for more information on CES 20074 and CES 20085 oil specifications.

All CWI engines using stoichiometric combustion are compatible with CES 20092 oils. According to Cummins, these platforms will benefit from a transition to CES 20092 oils, which require a more modern oil additive system than previously used for CES 20074 or CES 20085 oils. The new specification requires a much stronger antioxidant combination to provide protection at the high temperatures experienced in modern natural gas engines. The range of allowable ash levels for CES 20092 oils (0.7-0.9%) is similar to the CES 20085 specification.

Lean burn legacy engines should continue to use CES 20074 oils until further notice.

CES 20092 is completely backwards compatible with CES 20085. Cummins recommends all customers using CES 20085 oils should plan to transition to CES 20092 oils. Customers using stoichiometric burn engines with CES 20074 oils should also transition to CES 20092.

The only oil presently meeting the CES 20092 specification is Valvoline Premium Blue One Solution 9200, available in SAE 10W-30 and 15W-40 viscosity grades.

Valvoline introduced Valvoline™ Premium Blue One Solution™ 9200 this March as a “universal” engine oil approved for use in natural gas, API CK-4 application diesel and API SN application gas engines for fleets operating multiple truck engine types. In Addition to meeting the new Cummins CES 20092 spec for natural gas engines, as well as CES 20086 and CES 20085 approvals, Valvoline says it also meets Mack EOS-4.5, Volvo VDS-4.5, and Detroit Diesel DFS 93K222 specs.