Research is currently being undertaken to develop improved suspensions for Combat Support Vehicles (CSV's). Part of this work focuses on the feasibility of using intelligent suspensions to continuously optimise the vehicles performance as the operating environment changes. For an intelligent suspension to be effective in this case, it should enable increased vehicle speed from an improvement in ride performance whilst not detracting from vehicle safety or handling performance.This paper investigates the power consumption of a CSV vehicle with a slow-active suspension. From the power consumption it is possible to estimate the extra fuel consumption and reduction in vehicle top speed. The power consumption was evaluated for a set of representative terrain profiles and vehicle speeds, demonstrating the trade off between suspension power consumption and ride performance improvement.