The properties of three different pitch-interconnected hydro-pneumatic suspensions are systematically explored. The vertical and pitch mode properties of the proposed suspensions are derived through formulation and analysis of a generalised pitch plane model. The results suggest that the pitch-connected suspensions offer superior flexibility for enhancing the pitch mode properties, without affecting the bounce mode properties. The dynamic characteristics of the proposed pitch-connected suspensions are further evaluated for a two-axle heavy vehicle under braking and road inputs. The results demonstrate that the proposed pitch-connected suspensions could offer significant benefits in improving both the handling and ride qualities of heavy vehicles.