Engine Oil Specifications 101 – UnderhoodService

Engine Oil Specifications 101

Engine oil can be one of the most confusing and controversial products to select for a vehicle. The reason for this is that engines are becoming more stressed and require lubricants with specific attributes to protect and power gasoline engines with turbochargers, direct fuel injection and advanced internal components.

Engine oil can be one of the most confusing and controversial products to select for a vehicle. The reason for this is that engines are becoming more stressed and require lubricants with specific attributes to protect and power gasoline engines with turbochargers, direct fuel injection and advanced internal components.

The overseers of oil specifications are still ILSAC, API and ACEA. But, as engineers look to improve power and economy, they are forced to issue proprietary oil specifications. These specifications are typically listed on the back of the bottle, on a product data sheet or the oil manufacturer’s website. 

ILSAC Rating

The International Lubricants Standardization and Approval Committee (ILSAC) is the gatekeeper of oil standards.

ILSAC GF -1,-2,-3,-4 and -5 are specifications for multi-grade oils that were first rolled out in 1992. GF-5 certified oils are compatible with previous GF-1 to GF-4 oils of comparable weights.

The GF-5 requirements were rolled out in 2010. They were designed to provide improved high-temperature deposit protection for pistons and turbochargers, more stringent sludge control, improved fuel economy, enhanced emissions control system compatibility, seal compatibility, and protection of engines operating on ethanol-containing fuels up to E85.

Higher viscosity oils cannot meet an ILSAC GF-5 rating. The GF-5 rating corresponds closely to the API SN rating.

ACEA Rating

European car manufacturers are perhaps the most focused on extended interval oil options, and these manufacturers abide by the standards set by the European Automobile Manufacturer’s Association (ACEA). These standards are based on testing developed by the European Engine Lubricants Quality Management System (EELQMS).

“A” and “B” (1-5) rated oils are stable, stay-in-grade oils intended for use at extended drain intervals in gasoline and diesel engines (car and light van). These are specifically designed to be capable of using low-friction, low-viscosity oils with a high temperature/high shear (HTHS) rate viscosity.

The “C” rating designation is for catalytic converter-equivalent oils. They are A5/B5 oils with a low sulfated ash, phosphorous and sulfur content.


BMW has only three oil specifications — BMW Longlife-98, BMW Longlife-01 and BMW Longlife-04. These oils typically meet and exceed ACEA and API SJ/CD standards.

BMW Longlife-04 oils require special BMW approval for fully synthetic long-life oil. Longlife-04 is backdate compatible where Longlife-98 or BMW Longlife-01 is recommended.


Chrysler has three proprietary oil specifications for gasoline engines. They call these standards Chrysler Material Standards or MS specifications.

The first specification is MS-6395 that covers 5W-20, 5W-30, 5W-20 and 10W-30 oils. This standard follows the API SM GF-5 standards with a few extra tests for Chrysler engines. Most GF-5 approved oils meet these standards. The MS-10850 specification is for SRT8, SRT10 and SRT6 engines that call for 5W-40 oil. MS-12633 approved oils are for SRT engines that specify 0W-40 oil.


In Europe, Fiat recommends ACEA grade oils for their cars and trucks. In North America, Fiat recommends oils that meet the requirements of Chrysler MS-6395. But, for Abarth and turbocharged models, they may specify an oil that meets specific ACEA or higher Chrysler specifications.


Ford structures oil specifications around the weight of the oil. The WSS specifications for gasoline engine oils were last updated in 2012. WSS-M2C945-A and WSS-M2C946-A oils typically meet API SN GF-5 standards with a few extra tests performed on Ford engines. These standards cover 5W-20 and 5W-30 oils. WSS-M2C947-A approved oils are for 0W-30 oils and are typically synthetic.

GM Dexos Motor Oil Specifications

GM Dexos1-approved oils are recommended for all 2011 and newer GM vehicles with gasoline engines. Dexos1-approved oils are designed to work with the oil life system in GM vehicles. These oils are designed to reduce carbon deposits in the combustion chamber that can occur in some Ecotec engines.

GM revised Dexos1 specifications in 2015. Oils that meet this standard are often labeled Dexos1 Gen2, but many oils do not include the Gen2 on the label due to confusion with Dexos2 oils for diesel engines. Dexos1 Gen2 oils are formulated to reduce incidents of low-speed pre-ignition (LSPI).


Honda specifies mostly API-approved 0W-20 or 5W-20 oils, but there is a unique spec to note for the 2007-2012 Acura RDX. This requires Honda/Acura HTO-06 motor oil, which was developed to ensure adequate protection for turbocharged and variable valvetrain engines.


Mercedes-Benz oils follow the same oil specification trends as other German manufacturers that have had to update to lighter-weight oils to meet Euro 4 emission standards and drain intervals. Some of these standards even cover Chrysler vehicles. For a full list of approved Mercedes-Benz oils, head to bevo.mercedes-benz.com.


Toyota, Subaru and Nissan recommend using API-approved engine oils for the weight that meet GF-5 specifications.


Volkswagen has issued 11 different motor oil specifications over the years. Most Volkswagens made after 2000 have the long drain interval option or WIV (Wartungs Intervall Verlängerung) or longer service intervals. Volkswagen started with VW 500.00 and it is currently developing VW 509.00.

The progression of its oil standards is in response to changing vehicle injection technology (gas and diesel) and lighter oil viscosities. Also, specifications were issued to meet changing emission mandates limiting sulfur, ash and phosphates (SAP).

Some of the standards and variants are for vehicles you may never see, like the Lupo. Many of the oil standards supercede or improve previous specifications and are backdate compatible. This means a vehicle that specifies VW 502 oil can use VW 504 oil.

To select the correct oil that meets VW standards, check the owner’s manual or repair information database. Your oil supplier may even have a guide on its website. You can also check the oil manufacturer product data sheets to see which specifications an oil meets. You will be surprised what mass-market synthetic oils meet VW’s stringent specifications for VW 507.

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