A suspension mechanism for a reel mower vehicle, having arm members coupled between a vehicle and a cutting unit, a lever member coupled with each arm member, and a hydraulic cylinder coupled the lever member. A hydraulic circuit actuates the cylinders for lifting the arm members and cutting units to a transport position. A variable restriction valve is provided for causing the cylinders to apply a downforce to the arm members and cutting units for securing the cutting units against the ground over irregular ground conditions, and is adjustable for varying the magnitude of the downforce.