Durability assessment for suspension systems requires loads on each component from different road profiles. These road loads are typically obtained by testing the vehicle on the proving grounds. If a new vehicle is to be assessed for durability early in the design phase, a prototype is required which can be time consuming and expensive. Given the large number of configurations offered in the truck industry, it is not practical to measure data for each one. The only options would be to depend on generic load cases or to use a virtual method that can translate limited measurements to various configurations. If the road profiles for the proving grounds can be captured based on measurements on a few vehicle configurations, then they can be applied to new CAE full vehicle models to obtain road loads for preliminary analysis. Roush CAE has successfully implemented a method called virtual iterations to back calculate the road profiles from the CAE model of any vehicle that has been tested on the desired tracks. This paper presents an example problem discussing the basic full vehicle model setup and the processes involved. A linear transfer function is derived to estimate the first iteration of tire patch inputs. These tire patch inputs are applied to the full non-linear model to assess the spring/ damper displacements. Depending on the deviation in results (test vs CAE), the tire patch inputs are iteratively corrected. The final tire patch inputs are adjusted for changes in wheel base and applied to a vehicle with similar suspension systems. Correlation results are shown with acceptable relative damage values for various events like resonance roads, cobblestones, and chuckholes.