Short answer
MS-6395 is a Chrysler material standard for gasoline engine oil, now maintained by Stellantis. Chrysler service guidance has said API-certified oils should also meet MS-6395, because it adds requirements beyond API certification. Many Chrysler, Dodge, Jeep and Ram gasoline engines list it alongside a viscosity grade such as 0W-20, 5W-20 or 5W-30.
What “MS” means
MS stands for material standard, Chrysler’s internal engineering standard system. It is not a military standard, despite a common misreading. MS-6395 is the long-running standard for oils used in the company’s mainstream gasoline engines.
The standard carries a letter suffix that marks each revision, such as MS-6395-N or later. Owner’s manuals often print only “MS-6395,” so the oil’s data sheet is where the revision letter usually appears.
How it relates to API and ILSAC
MS-6395 is written on top of the industry baseline. Chrysler bulletins have advised that oils carrying the API certification mark should also meet MS-6395, because the standard includes Chrysler requirements that API licensing does not cover.
As API and ILSAC categories advance, the MS-6395 revision is updated to reference them, which is why older bulletins describe its relationship to earlier API categories differently than current ones.
Which engines call for it
MS-6395 typically appears in manuals for Stellantis gasoline engines sold in North America, including Pentastar V6 and HEMI V8 applications, each with its own viscosity grade.
Some high-performance, European-derived and diesel Stellantis engines specify different material standards instead. Ram diesel engines, for example, follow separate Stellantis and engine-maker requirements, so do not apply MS-6395 to them by default.
Checking an oil against MS-6395
Look in the owner’s manual for the exact grade and standard, then check that the current product data sheet lists MS-6395. Some marketers list the revision letter as well.
If a bottle shows only the API service symbol and the grade, it may be a suitable oil, but it does not confirm MS-6395. Keep that distinction in mind for warranty paperwork.
Frequently asked questions
Does the MS-6395 revision letter matter?
The letter marks the version of the standard. Manuals often list only MS-6395, so check the oil’s current data for the revision it was tested against.
Do Ram diesel trucks use MS-6395?
No. Ram diesel engines use separate oil requirements listed in the diesel owner’s manual.
General maintenance information. Always follow your vehicle or equipment manufacturer’s requirements and the current product data. Questions? Email [email protected].
