Shaker assemblies for dewatering slurries are disclosed. The shaker assemblies may include a positioning device which limits movement of the vibratory frame of the shaker assembly relative to a subframe when the vibratory frame is moved from a raised operating position to a lowered position. The positioning device may guide the vibratory frame as it is lowered from the raised position to the lowered position. In some embodiments, the shaker assembly includes a locking device for locking the vibratory frame to the subframe when the vibratory frame is in the lowered position.