In kinematic and compliance testing for suspensions, great importance is attached to the measurement of the instant centre and roll centre. As the suspension construction is truly three-dimensional, the screw axis theory can afford a much more accurate kinematic analysis. The purpose of this study was to present a vector finite displacement method (FSA v ) for the kinematic analysis of instant centre and roll centre of suspensions. Two suspension simulation models, with and without approximately singular screw parameter, respectively, were employed to investigate the efficiency of the proposed method. It was found that the FSA v method prevailed over the method of general finite screw axis. In addition, it was not necessary to calculate the velocity matrix from the derivatives. This proposed method, therefore, is suitable for determining the roll centre height and the related parameters of instant centre. Moreover, it can be expanded for the measurement of the kingpin axis as well.