The invention relates to a forest machine, comprising a chassis having sides, a swing bogie mounted on bearings to the chassis, comprising a swing frame, second sides and at least two wheels, a swing bearing attaching the chassis to mount the swing bogie, a power transmission arranged through the swing bearing in connection with the chassis, a support formed by two pairs between the chassis and the swing frame, each pair having a protrusion as a support surface and a rail as a counter surface to transmit lateral forces between the chassis and the swing frame during contact between the two surfaces, wherein each pair is located at a distance from the swing bearing on separate side of the swing bearing, and in each pair, one of the protrusions and the rail is attached to the side of the chassis and other to the second side of the swing frame.