A method for controlling a powertrain system of a heavy-duty vehicle, the powertrain system having at least one differential arrangement for receiving torque from a propulsion unit of the powertrain system and delivering at least a part of the torque to a set of first and second wheels, the method being implemented by a control unit, the method comprising determining a split-friction condition indicative of a wheel slip difference between the first and second wheels, wherein one of the first and second wheels defines a high-friction side of the differential arrangement and the other one of the first and second wheels defines a low-friction side of the differential arrangement; determining a target wheel slip for the high-friction side; and in response to the determined split-friction condition; controlling a brake force on the low-friction side of the differential arrangement based on the target wheel slip on the high-friction side.

A movable body includes: a rotating body that generates advancing power; a movable body main body that rotatably supports the rotating body; an electric motor that is supplied with electric power to rotate the rotating body; and at least one electric power generating unit including an internal combustion engine, an electric power generator that generates the electric power by an output of the internal combustion engine, and a support structural body that supports the internal combustion engine and the electric power generator and is attachable to and detachable from the movable body main body while keeping supporting both of the internal combustion engine and the electric power generator.