An automatic system for sorting items, such as small parcels, into groups bound for different geographical locations is described. The system uses tilting trays arranged at multiple levels, with all the trays being mounted on carriages traveling on a single monorail. The trays are tilted at the proper output chutes by cam roller mechanisms which are appropriately inserted into the path of cams on the trays under the coordination of a digital controller. A simple drive mechanism moves the carriages along the monorail using a drive roller which presses against the carriages. The carriages may be linked by a pliable linkage assembly that does not include mechanical hinges or like mechanisms. The system is easy to repair and operates at low noise levels.