A wheelset bearing for a rail vehicle includes a rolling bearing assembly (7) with three bearing rings (4, 8, 9), specifically two inner rings (4, 8) provided for connection to a wheelset shaft (2) and one outer ring (9) provided for connection to a housing (6). The rolling bearing assembly (7) is designed as a quadruple-row angular contact ball bearing in an O arrangement, and two rolling element rows (16, 17) are provided contacting a first inner ring (4) in order to absorb axial forces in a first direction and two rolling element rows (18, 19) are provided contacting a second inner ring (8) in order to absorb forces in the opposite axial direction. A rail vehicle with such an arrangement is also provided.

A wheel bearing assembly for a motor vehicle includes a housing having an interior, at least one bearing in the interior including a first bearing ring and a second bearing ring rotatably disposed relative to the first bearing ring, a plurality of rolling elements disposed between the first bearing ring and the second bearing ring, a lubricant in the housing interior in contact with at least a part of the at least one bearing, an axle connected to the at least one bearing, a sensor in the housing interior in contact with the lubricant, the sensor being configured to sense at least one property of the lubricant and to output a signal indicative of the at least one property of the lubricant, and a display unit outside the housing interior and in communication with the sensor, the display unit being configured to produce an output based on the signal.