What is the “correct oil”? Engine oil specifications define performance against a range of criteria; engine cleanliness, wear protection, fuel economy, resistance to oxidation and breakdown, and more. Specifications are regularly updated to keep pace with advances in engine technology.
In large part they are standardised across the automotive industry in the form of service classifications such as API SN, ILSAC GF-5 and ACEA C2. Engine oil manufacturers qualify their products by passing laboratory and engine test “sequences” defined for each classification. Engine oils qualified to one or more of these performance classifications provide baseline protection for the majority of vehicles. Engine oil manufacturers qualify their products by passing laboratory and engine test “sequences” defined for each classification. Engine oils qualified to one or more of these performance classifications provide baseline protection for the majority of vehicles.
Increasingly, vehicle manufacturers recognise these specifications do not adequately address the particular and sometimes unique design features of their engines. Given their investment in technical development and promise to the customer of long warranty protection, it is entirely reasonable that OEMs build additional “layers” onto the industry standards to define higher performing, more robust oils tailored to their engines. Many manufacturers today, particularly those from Europe, develop their own engine oil specifications. To qualify a product, lubricant manufacturers must submit a sample for rigorous lab and engine testing at their own expense, which may take many months and cost up to A$1.5 million.
If successful, the product is determined to fulfil all performance and warranty requirements and the manufacturer earns a formal ‘APPROVAL’, which may be displayed on package labels and product literature. Most OEMs publish controlled lists of oils they have approved, so workshops can identify which products are suitable for each vehicle. These approvals are especially important for cars under warranty, as the first question in a warranty claim is often “did you use an OEM approved lubricant”.
OEM specifications and approvals can apply to transmission and axle lubricants as well as engine coolants, which increases the complexity in the car maintenance field. It makes sense that a car’s lubrication requirements are best understood by the engineers who designed it.
An oil with formal OEM approval has been tested in the same hardware and components built into that car. It protects the vehicle warranty and may be a requirement to make sure the vehicle meets its fuel economy, service life and emission expectations. This can be especially important as the oil ages and is no longer “as new”. If a vehicle needs an OEM approved product to maintain warranty, this is generally stated in the owner’s manual.
IS THERE A DIFFERENCE BETWEEN AN OIL THAT CARRIES A FORMAL OEM APPROVAL AND AN OIL THAT CLAIMS TO “MEET THE REQUIREMENTS” OF AN OEM STANDARD?
"The answer is most certainly yes! An ‘APPROVAL’ demonstrates the manufacturer has taken the time and effort to design and formulate a product to an exacting set of standards, then invested in its testing and qualification. All car manufacturers open the approval process to any oil manufacturer who is willing to submit their product and pay for the test program. Protection at this level clearly comes at a price, frequently it is only a full synthetic lubricant that can pass these tests. A claim on a package label or product bulletin that an oil “meets the requirements” of a standard or specification is a much weaker indicator of performance and is based mainly on the oil manufacturer’s own judgement."
FOR WARRANTY PURPOSES SUCH A CLAIM IS UNLIKELY TO BE SUFFICIENT PROOF OF THE OIL’S SUITABILITY.