The invention provides a grease composition comprising: (a) a lubricating base oil; (b) a polymeric thickener comprising a mixture of (1) a (co- or homo)polymer of propylene with a weight average molecular weight of more than 200.000 and (2) a (co- or homo)polymer of propylene with a weight average molecular weight of less than 200.000; and (c) a polar wax. The invention further provides a mechanical component having a metal surface onto which a layer of the grease composition according to the invention has been applied. The invention also relates to the use of a polar wax in the preparation of a grease composition for bearing applications, and the use of a polar wax in a grease composition for bearing applications. In addition, the present invention relates to the use of the grease composition for reducing friction in a bearing, between bearing components or within a bearing application system. The invention also relates to a method for preparing the present grease composition.