In contrast to conventional solid-state lubrication, the additivation with nanostructured particles not only facilitates the production of stable dispersions but also assures that particles will intrude quickly into the surface contact zone and create a protective layer, especially when parts with low surface roughness and materials with low hardness are used. In this contribution, we discuss the tribological performance of a dispersion of titanium dioxide (TiO2) nanostructured particles in car engine base oil for three different iron carbon alloy materials (bearing steel, carbon steel and cast iron) in a disc–disc tribometer. We show that our formulations reduce friction in a bearing steel—carbon steel configuration. Whereas this effect could not be verified for the other two iron carbon alloy combinations. We attribute the observed friction reduction to a lubricating titanium (dioxide) overlayer that builds up on the carbon steel surface and is detected by element-specific energy dispersive X-Ray analysis (EDX).