A hydraulic actuator for a vehicle suspension includes: a pump assembly including an electric motor coupled to first and second pumps to transfer hydraulic fluid to a discharge header; a first isolation valve having an elastomeric seat and configured to selectively block fluid flow from a port in fluid communication with a height-adjustable damper to the discharge header; and a second isolation valve having a metal seat and connected in series with the first isolation valve to selectively block fluid flow from the port to the discharge header. The first pump transfers hydraulic fluid from a supply fluid passage to a first discharge header, and the second pump transfers hydraulic fluid from the supply fluid passage to a second discharge header. A recirculation valve selectively controls fluid flow from the second discharge header to the supply fluid passage.

A damper control system includes a controller configured to estimate a temperature of a damper fluid based on data relating to heat added to and heat removed from the fluid. At least one damper is operatively coupled to the controller, and the controller is configured to control a size of a damper flow path of the at least one damper based on the estimated temperature. Methods relate to controlling at least one damper based on an estimated temperature of a damper fluid.

An internal stroke sensor for an IFP shock assembly is disclosed herein. The shock assembly includes a damper chamber and a damping piston coupled to a piston shaft. The damping piston disposed in the damper chamber and axially movable relative to the damper chamber, the damping piston separating a compression portion from a rebound portion within the damper chamber. The shock assembly also includes an internal floating piston (IFP) and an IFP location sensor. The IFP location sensor to determine a position information for the IFP. A processor is configured to receive the position information for the IFP from the IFP location sensor and utilize the position information for the IFP to determine a shock stroke position of the shock assembly.

A spring-damper system for a wheel suspension of a motor vehicle comprise a support spring of a spring constant k.sub.T and a damper acting in parallel to the support spring. A spring element is arranged in series with the support spring and can be controlled by means of a controller in such a way that a total spring constant k.sub.G of the spring-damper system can be varied.