A four-degrees-of-freedom roll plane model of a heavy highway vehicle is developed to investigate the ride and anti-roll properties of two different hydropneumatic strut designs, unconnected and interconnected in the roll plane. Three different interconnections, involving flows across different chambers of the right- and left-compact struts, are realized for the analyses. The analytical models are solved to derive the static and dynamic properties of various unconnected and interconnected configurations in terms of vertical spring rate, effective vertical mode damping, effective roll stiffness and roll mode damping. From the results it is concluded that roll plane interconnection of the suspension struts offers considerably potential for enhancing the anti-roll properties, with insignificant influence on the vertical ride properties.  The analytical models are further analyzed under deterministic and random vertical road and roll moment arising from directional maneuvers. The relative performance potentials of interconnected suspensions are presented in terms of vertical and roll acceleration transmissibility under a harmonic excitation transient vertical and roll responses under a transient road bump and roll moment excitations, and power spectral densities and RMS values of the sprung mass responses to random road excitation