Infinite-life multiaxial fatigue criteria had only the ability to evaluate whether or not fatigue failure is to occur to a mechanical componente once subjected to multiaxial fatigue loadings. Carpinteri e Spagnoli proposed a modification to their own model, substituting both fully reversed bending and torsion fatigue endurance limits, f1 and t−1 respectively, introducing into the equation a new variable nf, allowing the model to predict the fatigue-life of the mechanical component. The main goal of the presente study is to assess the accuracy of the modified model via experiments. The research methodology consisted in determining m and m (asterisk), which are the slopes of the S-N curves for fully reversed bending and torsion experiments on regards to DIN 42CrMo4 steel when plotted into a log-log scale, providing means to apply the model. Since there is no analytic solution to the model, the criterion s equation has to be solved numerically. Furthermore, the present study discusses the possibility of a direct relation between amplitude of normal stress, amplitude of shear stress and number of cycles to failure. The modified Carpinteri & Spagnoli s criterion proved itself to be partially consistent, presenting both accurate predictions of torsional fatigue-life and discrepant results for axial loadings. For combined loadings, the model provided two consistent results while another experimental point was proved far off. The final assessment on regards to the model s accuracy depends on more experimental points.