Abstract: A hydraulic engine mount includes opposed mounting members secured to an elastomeric body and a base, respectively, with an orifice plate assembly interposed the body and the base to define a pumping chamber and a reservoir for hydraulic fluid to flow therebetween through an orifice track formed by the orifice plate assembly. An elastomeric decoupler disk is secured in a recess formed between two orifice plates of the orifice plate assembly and defines a gas spring or cushion space which may be filled or vented by a removable plug in one of the orifice plates. Improved dynamic rate and damping at low amplitude inputs to the mount are provided by the gas cushion biased decoupler as compared with a decoupler type mount without the gas cushion bias. The mount provides an advantage over conventional decoupled hydraulic mounts in that very strict dimensional tolerances are relaxed and performance characteristics, as well as ease of manufacturing, are improved.