A steering system is provided for an agricultural vehicle having steerable wheels of a first wheel set, first and second steerable wheels of a second wheel set, and a steering input device configured to receive a manual steering input for the wheels of the first wheel set. The steering system includes first and second hydraulic steering devices coupled to the first and second steerable wheels of the second wheel set； a valve assembly configured to hydraulically control the hydraulic steering devices to steer the wheels of the second wheel set； and a controller configured to determine steering commands and provide the steering commands to the valve assembly. In a rear stability mode, the valve assembly is configured to selectively dampen fluid flow between the first and second hydraulic steering devices.
