Next Generation Mineral Axle Oils for Long Drain Applications

It has long been the accepted norm that for commercial vehicle rear axles that in order to formulate axle oils with long drain capability it has been necessary to utilise part or even fully synthetic base fluid systems as passenger car rear axles were essentially “Fill for Life. However, a new specification for commercial vehicles in Europe is pushing for long drain Capability from Group 1 based mineral oils. The key properties for such a lubricant are: Improved oxidation stability, EP, seals and pitting durability in axle tests. When combined with other more recent OEM specifications for applications such as bus portal axles and improved efficiency to aid fuel economy, it is leading to the development of new advanced additive platforms to meet these exacting demands. This paper will explore the background to the new specifications and some facets of the performance of the resulting technologies.