Vehicle (24), preferably an agricultural spreader for delivering manure, with a truck box (10) and a hydraulic system (11), comprising a hydraulic pump (12) and motor (5) for driving a propulsion device arranged in the bottom of the truck box, which comprises at least one bottom chain (1) with associated idler wheels (3) and a chain tensioning device (2) for tensioning the bottom chain through an essentially linear displacement of at least one of the idler wheels. One or more hydraulic cylinders (4) form part of the chain tensioning device. The vehicle has a first operating mode, in which the bottom chain has a first direction of operation and a second operating mode, in which the bottom chain has a second direction of operation. The hydraulic cylinders have a first effective piston area (18) in the first operating mode and a second effective piston area (19) in the second operating mode. The first and second effective piston areas are different from each other. Method for the hydraulic tensioning of a chain tensioning device in an agricultural vehicle.
