HLPD oils have pronounced wetting and cleaning effects as well as assume a special position among HLP hydraulic oils as detergent (cleaning) hydraulic oils. Due to their good viscosity-temperature behavior, the carefully selected base oils ensure flow properties and performance, thereby ensuring low flow and friction losses. Contaminants are dissolved (detergent property) and kept in suspension (dispersant property), thus enabling cleaning of contaminated hydraulic systems. The functional elements of a hydraulic system then remain free of deposits and adhesions. Penetrating water is emulsified, and trouble-free operation of the hydraulic system is ensured.