While the American Petroleum Institute (API) is in charge of oil standards in the US, a different entity oversees European standards. The European Automobile Manufacturers’ Association (ACEA) has its own specifications for classifying oils. Before any European oil hits the shelves, it needs to pass ACEA standards and categorization. For the American market, ACEA classifications are especially important when servicing an imported European vehicle. Let’s look into ACEA oil standards and what you need to know when picking an ACEA-approved oil for your European vehicle.
Like its American counterpart, European motor oil is distilled and processed with various other additives to make it suitable for vehicle engines. ACEA-approved oil is formulated differently from API-approved oil. It follows different standards and is best suited for European vehicles. In fact, you’re not meant to substitute one for the other.
If a vehicle’s been manufactured for the European market, using ACEA oil is a must. Most American oils are incompatible with European engines, and using them can lead to increased wear and tear, performance issues, voided warranties and more. Make sure you pay attention to what the manufacturer calls for too. Some vehicles, like BMWs models manufactured before 2014, use Castrol oil.
Here are a few important engine oil terms to know before learning more about ACEA classifications:
The European Automobile Manufacturers’ Association is globally abbreviated as ACEA due to its original French name, Association des Constructeurs Européens d’Automobiles. It was founded in 1991 by 15 of the most significant European car manufacturers at the time, including BMW, DAF, FIAT, and General Motors Europe. ACEA has welcomed other non-European motor vehicle manufacturers with research centers and production facilities located within the European Union. While ACEA oversees a number of different subsectors in the European automotive market, one of its regular duties is defining European oil standards.
Every few years, ACEA updates its engine oil standards, and each update is referred to as an ACEA Oil Sequence.
The total base number, or TBN, indicates the oil’s ability to neutralize the acids formed when the engine runs.
HT/HS stands for high temperature/high shear. It affects fuel economy and relates to engine oil viscosity at high temperatures under continuous shear. Oils with HT/HS increase fuel efficiency and reduce greenhouse gas emissions. They also protect the engine from wear and tear.
SAPS is the acronym for sulfated ash, phosphorus, and sulfur. If engine oil is low-SAPS, it means it has lower percentages of these compounds and elements. Mid-SAPS oils have reduced levels of SAPS and are more efficient than traditional oils. Meanwhile, full-SAPS have no chemical limits relating to the said elements.
ACEA oil specifications consist of a letter and a number. The letter signifies the oil’s class or type, and the number indicates its category. ACEA first divides oils by class or type and then by applications and features. There are three main groups:
ACEA A/B is the category for oils suited for high-performance petrol (A) and light-duty diesel (B) engines. They’re stable, stay-in-grade lubricants that are further broken down into the following subcategories:
ACEA C-grade oils are light duty and work with three-way catalysts (TWC) and diesel particulate filters (DPF). The “C” stands for catalyst-compatible. These oils have mid- or low-SAPS levels. Phosphorus and sulfur, which have anti-wear, anti-friction, and antioxidant properties when used as additives in oils, can damage a vehicle’s diesel particulate filter and two-way catalytic converter in high quantities, which is why this category exists.
ACEA C-grade oils can also be divided by SAPS levels. Low-SAPS ACEA C-grade oils include the C1 and C4 oils. Mid-SAPS oils in the ACEA C classification are the C2, C3, C5, and C6 oils. Here’s more information about these oils:
Mercedes diesels need specific types of oil for low ash. Not using those oils will damage the engine and exhaust aftertreatment.
–Anthony Harlin, ASE Certified Master Automobile Technician
ACEA E-grade oils are formulated for heavy-duty diesel engines. They’re further classified into the following categories:
Both ACEA and API work to ensure that the oils under their jurisdictions follow a certain standard dictated by their area laws and manufacturer needs. That said, ACEA specifications tend to be more detailed and specific, categorizing European oils into several subcategories based on engine type, SAPS, and more. ACEA focuses on environmental concerns when categorizing European oils, including emissions and fuel economy into their oil tests. Meanwhile, API tends to focus on deposit control and protection from wear and tear. ACEA specifications are also updated more frequently than API specifications.
This is in line with the design trend in European vs. American engines as well. European vehicles tend to have smaller engines with higher power output. They need oils that address the increased emissions from these designs. Similarly, European car manufacturers introduce new engine technologies more often, which means more frequent ACEA specification updates.
Now you see why it’s important to only use European oil in your European vehicle. ACEA specifications are more stringent, designed to grade oil to suit European engines. So the next time you need to top up your European vehicle’s oil, be sure to check which type of ACEA oil it needs.
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.