From the existing experimental results and previous studies, the torque load has great influence on the mesh and dynamic characteristics of hypoid gear drive. To have more insights on the load dependent mesh parameters and dynamic response of hypoid and spiral bevel gear, a load dependent mesh model is developed by using 3-dimensional loaded tooth contact analysis (LTCA). The contact ratio and time-varying mesh parameters including the mesh stiffness, transmission error, mesh point and line-of-action of the mesh force are examined within a wide torque range. Then a nonlinear multibody dynamic analysis is performed considering the effect of backlash nonlinearity. Simulation results show that the contact ratio and mesh stiffness generally increases as the toque load increases. The effect of torque load on dynamic mesh force is found to be frequency dependent due to the resonance frequency shifts and peak magnitude changes. This study provides an in-depth understanding of hypoid gear tooth load sharing and dynamic behaviors in terms of change in operating load. Therefore, the proposed model can be employed to assist in gear design optimization.