<p>Prior investigations into mechanisms with clearances have predominantly concentrated on planar mechanisms and simple three-dimensional mechanisms. Few pertinent studies have been undertaken in the domain of hybrid mechanisms that account for the synergistic effects of three-dimensional joint clearances and flexible components. This paper examines the combined effects of clearances and flexible components on the 3-PRPaR-RUPUR hybrid mechanism, focusing on acceleration, velocity, displacement, driving force of original components, impact force within clearances, central trajectory at clearances, dynamic accuracy reliability, and nonlinear characteristics. Initially, a theoretical model based on Absolute Nodal Coordinate Formulation for a three-dimensional two-node flexible beam element is developed. A kinematic theoretical model for revolute joint clearance has been developed. Secondly, the impact force at clearances is modeled by integrating the Flores normal contact force theoretical framework with the modified Coulomb tangential theoretical framework. A dynamic model of a rigid-flexible coupling for the 3-PRPaR-RUPUR hybrid mechanism is formulated based on Lagrange multiplier theory. Subsequently, employing the Stress-Strength Interference model and the first-order second-moment theoretical method, a reliability theory model for the mechanism was constructed to examine the impact of 3D revolute joint clearances and component flexibility on mechanism reliability. The mechanism's nonlinear characteristics are examined through phase diagrams, Poincaré maps, and the maximum Lyapunov exponent. The findings demonstrate that the combined influence of 3D revolute joint clearances and flexible components impacts the mechanism's stability, leading to variations in its dynamic response, producing chaotic phenomena, and diminishing its reliability. The incorporation of additional clearances may diminish the chaotic phenomena of the mechanism at specific intervals, thereby enhancing its reliability.</p>