Future developments of engine oils
Ever stricter exhaust standards keep requiring new lubricants
Vehicle manufacturers issue new oil approvals all the time and terms such as "low-" and "mid-SAPS oils" can be found in all papers and specialist journals. The European engine oil market is subject to radical changes at the moment. The introduction of new and stricter EU emission standards necessarily leads to the development of new engine technologies and exhaust treatment systems, as for instance particulate filters and NOx storage catalytic converters.
"For the lubricant manufacturer these new technologies mean the adaptation of the constructional element engine oil in ever shorter intervals as well as the development of a new generation of lubricants", Sven Köhler, product manager Automotive at the lubricant supplier Addinol, describes the current situation. This is the only way for vehicles to meet the respective limits. The Euro-4 standard brought about dramatic changes for the additives of engine oils. Oil manufacturers have developed new additive components meant to reliably master the requirements of the engine ensuring the efficiency of exhaust treatment at a high level at the same time.
Diesel particulate filters allow very small quantities only of phosphor, sulphur and sulphated ash in the engine oil for wear protection and lubrication – otherwise they are clogged. These lubricants, especially developed for modern diesel engines with diesel particulate filters, are known as low- or mid-SAPS oils (i.e. oils with a low to medium content of sulphated ash, phosphor and sulphur).
New European oil standards
The European engine oil specification ACEA takes the new and higher requirements on engine oils into consideration. For passenger cars they have been defined in a separate standard, ACEA C, in 2004 for the first time. In 2008’s issue of ACEA there are four different classes based on different requirements of vehicle manufacturers: ACEA C1 to C4. Their main difference lies in the allowed content of the substances described above.
The same applies to ACEA sequence E for commercial vehicles. ACEA E6 and ACEA E9 also require the limitation of ash-forming substances which means that also here low-SAPS engine oils are becoming more and more important.
A new and quite strong focus of customers and thus also of vehicle manufacturers is the saving of fuel and the lubricant’s impact on the reduction of wear inside the engines. High-temperature-high-shear viscosity is highly important in this context. Oils with a value of ≤3.5 mPa*s have a so-called decreased HTHS-viscosity and are supposed to enable a lower fuel consumption. However, they can only be applied in engines designed for them specifically.
As a result of the stricter demands on engine oils the special approvals of vehicle manufacturers are going to increase further as is the number of special oils for single types or manufacturers. "Low-SAPS engine oils are going to be the dominant ones in future, especially with regard to the upcoming Euro standards there is hardly any alternative", according to Köhler.
Addinol (Additives in Oil) was one of the most famous brands of the GDR and represented a broad range of lubricants. Today, after the German Reunification and a new start, the company from Saxony-Anhalt offers quality lubricants up to the latest state-of-the-art. Current example: ADDINOL Mega Power MV 0538 C4 SAE 5W-30 developed for the application in modern Renault diesel engines with exhaust treatment: it meets ACEA standard C4-08 and is approved according to Renault RN0720.
German article published in kfz-betrieb 6/2010 (view article here)