Weight transfer system for an agricultural machine

A pair of grain drills are positional for side by side operation in the field and connected to a towing tractor by weight transfer hitch having a rear end portion connected to the grain drills and a forward tongue portion having its front end connectable to the tractor drawbar and its rearward end totally connected to the forward end of the rear hitch portion for swinging about a transverse horizontal pivot. A hydraulic cylinder has its ends respectively connected to the tongue and the rear hitch portion and pressure to the cylinder is controlled by an adjustable pressure control valve that delivers pressurized fluid from the tractor hydraulic system to the cylinder at a pre-selected pressure below the tractor system pressure, whereby the force exerted by the cylinder on the tongue transfers a portion of the weight of the machine to the tractor drawbar.