Abstract: A loading dock leveler is mounted in a dock slab by pre-casting and placing a four sided monolithic concrete box insert defining a bottom, two lateral side walls, a rear wall and an open front above the bottom and between the side walls, to provide a dock leveler pit. The remainder of the dock slab is poured around the precast box insert. Before or after placing and embedding the precast box insert, a leveler platform, base and extension mechanism are installed. An angle iron or other internal fixture can be embedded in the box insert during casting to provide a welding point for affixing one or both of a hinge leaf for the platform and a base of the leveler mechanism. The box insert also is provided with external protrusions such as a tenon-like bead protruding outwardly from the side and rear walls. When the slab is poured around the box insert, the tenon like protrusion engages mechanically in the slab as the pour cures.