A drive mounting apparatus and method for mixing assemblies, such as a side-entry mixer, that can move the drive of a mixer between a closed position and an open position, and by doing so, can provide an access opening through which maintenance operations can be executed inside the mixer. The apparatus has a bearing housing and a pivoting mounting door. The drive is mounted to the pivoting mounting door, and the pivoting mounting door can move between an open and closed position relative to the bearing housing.