A retarder arrangement (1) is configured to brake rotation of a shaft (3) of a vehicle (5). The arrangement (1) includes a retarder rotor (7), a retarder transmission (9), a lubricant feed conduit (11) arranged to conduct lubricant to the retarder transmission (9), a coupling device (13), and an actuator element (15). The actuator element (15) is moveable between an actuated position and an unactuated position to move the coupling device (13) between an engaged state and a disengaged state. The coupling device (13) is configured, in the engaged state, to connect the retarder rotor (7) to the shaft (3) via the retarder transmission (9), and in the disengaged state, to disconnect the retarder rotor (7) from the shaft (3). The lubricant teed conduit (11) includes a valve (17) mechanically connected to the actuator element (15). The present disclosure further relates to a transmission arrangement (40), a power train (50), and a vehicle (5).