1. A motion stabilizer for a combined vehicle including a tractor and a trailer connected to the tractor, the motion stabilizer comprising: a pendular motion determination unit configured to determine whether or not a pendular motion caused by a swaying motion of the trailer is imparted to the tractor; a braking control unit configured to exercise a braking control upon detection of the pendular motion; and an engine torque control unit configured to exercise an engine torque control for regulating an engine torque produced by an engine, which engine torque control includes placing a limitation on the engine torque upon detection of the pendular motion, wherein a start of the engine torque control unit relaxing the limitation on the engine torque is timed to occur prior to a start of the braking control unit bringing the braking control to an end.