This paper has made several contributions to hydraulic mount modeling. A continuous nonlinear decoupler model is developed to capture the amplitude dependent behavior of a typical hydraulic mount over low and high frequency ranges. The decoupler model also demonstrates decoupler resonance, which degrades high frequency characteristics of a generic hydraulic mount. In addition, this paper is the first to introduce a lumped parameter MDOF (Multi Degree Of Freedom) fluid column system that is shown to improve high frequency characteristics. Model parameters are identified by isolating components in an experimental test apparatus and applying system identification techniques. Model simulation results are validated with measured data over the full range of standard excitation conditions.