The thesis work is an investigation on passenger vibrational comfort and seat filtering: to perform this work a multibody model that simulates human-seat interface is analysed. Thesis starts from a multibody analysis in Adams Car environment, by the use of FCA proprietary tool, MB-SHARC, of a full vehicle model. By the analysis of experimental data done in Balocco Proving Ground on a vehicle with two passengers (driver and rear seat passenger) three different missions are analysed to perform a complete correlation of the vehicle: obstacle, a rough road and highway. Through the analysis of the amplitude of the signals, missions are split in two groups based on the amplitude of acceleration: this because the hydraulic components in the vehicle model and some components of the human-seat interface model show a quite different behaviour depending on the amplitude involved.