Nonlinear contact analysis can be closer to reality when dealing with contact problems, however, the complicated contact parameter setup, low computation efficiency and the computation convergence with no guarantee, which make contact analysis difficult to be applied to engineering practice. Node coupling analysis is a linear analysis without convergence problem, so the node coupling analysis is superior to the contact analysis because of its lower computational expense. In order to explore the differences in the application between the two models and study the feasibility of using the node coupling linear analysis instead of the nonlinear contact analysis, the trackless telescopic gantry crane with 12 ton lifting capacity was taken as the example, and the finite element analysis software ANSYS was used to establish a contact model and a node coupling model. The influences of contact stiffness and friction coefficient on the calculation results was considered, and the equivalent stress differences of each contact part between two models were compared under the condition of telescopic leg extending. By comparing the computation results, it was found that the maximum equivalent stress of two models appeared at the crane frame where the lifting load was applied. Besides, there was no significant difference with the relative error was 1.3%. Furthermore, the equivalent stress value of each contact part had some differences since the node coupling analysis neglected the friction coefficient, therefore, the relative error can be reduced by selecting the appropriate friction coefficient in the contact model according to the relative sliding of the contact part. According to the results, considering the influence of relative sliding on the calculation results, node coupling analysis can simulate contact analysis favorably, for models with no high precision or no relative slip of the contact area, a simplified approach based on node coupling analysis can be used to replace contact analysis to improve computational efficiency.