To investigate the vibration characteristics of a landing gear gear-driven nose wheel steering system under transmission clearance conditions， this paper first conducts a simplified theoretical analysis to reasonably design anti-sway damping. Subsequently， the landing gear vibration coupled rigid-flexible multi-body dynamics simulation model is validated using both theoretical analysis results and vibration test results. Then， nonlinear factors such as gear transmission clearance and torque arm axial and radial transmission clearance are simultaneously considered in the vibration dynamics analysis， achieving a coupled rigid-flexible nonlinear dynamics model for landing gear with transmission clearance. Based on this model， a multi-factor study on the differences in vibration response characteristics is conducted. The results reveal that gaps can cause the landing gear to oscillate with constant amplitude， with gear transmission clearance having a greater effect on wheel swing angle than torque arm clearance. Additionally， the gap size is approximately proportional to the wheel swing angle. Increasing vertical load helps suppress vibration， while taxi speed primarily affects the wheel swing frequency. These findings provide theoretical reference for the design of landing gear anti-sway systems.