Hydraulically-driven dishwasher diverters are disclosed herein. An example hydraulically-driven dishwasher diverter includes a diverter housing having a plurality of wash zone openings defined therethrough corresponding to respective wash zones of a dishwasher, and a rotating cylindrical diverter valve including a valve outlet to fluidly couple a fluid flowing through the cylindrical diverter valve through one of the wash zone openings, a flexible portion adjacent the valve outlet to seal another one of the wash zone openings in response to fluid pressure in the cylindrical diverter valve while the valve outlet is fluidly flowing the fluid through the one of the wash zone openings.