Vertical excitations from obstacles on public road are typical and likely to increase vehicle interior vibration through major paths of wheel spindle-suspension-body. A new transient transfer path analysis(TTPA) methodology is presented combining the substructure reverse matrix method based on FRFs with operational excitation. Additionally, a new kind of experimental method is applied to solve an engineering problem and also validates the TTPA theory above. There are three steps in all. Firstly, vibration in Z direction of wheel spindle was collected in one proving ground and represented on MTS 320 road simulator bench after many times of iteration of piston signals. This procedure guarantees excitation decoupling in one certain direction so it leads to accurate frequency response functions(FRFs) under transient shocking excitation. Secondly, the new transient transfer path analysis approach was used to calculate vibration contribution of wheel-suspension-body. Finally, verify the validity of this new optimized TTPA via comparison of traditional substructure reverse matrix calculation and testing results. This method supplies a novel method of analyzing noise and vibration under transient loads for its convenience and accuracy of transfer path analysis.