Abstract: A filter device for transmission oil has a filter element (24) insertable into a transmission oil pan (70) with a filter medium (32) separating an unfiltered side from a filtrate chamber connected to an outlet (38, 50, 72), to which a suction oil pump can be connected. The filter medium (32) has a first structural layer (46) having a predetermined surface area and predeterminable filter properties and has a second structural layer (44, 60) having predeterminable filter properties. The surface area of the second structural layer (44; 60) is different from the surface area of the first structural layer (46). The structural layers (44, 46, 60) encompass an inner filter cavity (30) and are pleated having the same type of pleats. The pleated structural layers (44, 46, 60) extend in axial alignment between two end caps (22, 34) of the filter element (24).

Abstract: A filter device for transmission oil, having a filter element (24) which can be inserted into a transmission oil pan (70) and the filter medium (32) of which separates an unfiltered side from a filtrate chamber, which is connected in a fluid-conveying manner to an outlet (38, 50, 72), to which a negative-pressure device such as a suction oil pump, can be connected, wherein the filter medium (32) of the filter element (24) has at least one structural layer (46) having a predetermined surface area and predeterminable filter properties and having at least one further structural layer (44, 60) having predeterminable filter properties, wherein the surface area of the further structural layer (44; 60) is different from the surface area of the first structural layer (46), and wherein the respective structural layers (44, 46, 60) encompass an inner filter cavity (30), is characterized in that the respective structural layers (44, 46, 60) are pleated having the same type of pleats, in that the pleated structural layer