A dishwasher rack assembly includes a bottom wall formed of spaced apart lateral rods crossed by spaced apart longitudinal rods to define an open lattice structure. A plurality of fixed vertical tines extend upward from the bottom wall and are arranged in pairs along the longitudinal or lateral rods of the bottom wall with a defined space between adjacent pairs of the fixed vertical tines. A frame structure is provided with a shape and size so as to slide along the bottom wall between the pairs of fixed vertical tines. A plurality of vertical tines extend upward from the frame structure and are arranged in pairs along the frame structure. A securement mechanism is configured between the frame structure and the bottom wall to accommodate relative movement and anchoring between the frame structure and the bottom wall for variable positioning of the frame structure tines relative to the pairs of fixed vertical tines.