An agricultural harvester has a chassis carrying a header removably attached to a feeder housing for gathering a type of crop and feeding it into the agricultural harvester. The feeder housing is connected to a threshing and separating system for separating grain from MOG, which leads to a grain cleaning system for cleaning the separated grain. The grain cleaning system has at least one sieve operable to oscillate fore and aft, and at least one cleaning fan. The grain cleaning system also has a side shaker mechanism operable to produce a side to side shaking motion. A control system is connected to the side shaker mechanism and is operable to automatically adjust the amount of side to side shaking motion on the basis of the type of crop and on the basis of the amount of side slope upon which the agricultural harvester is situated.