An improved stabilizer for the steering of a vehicle. The stabilizer comprises a housing containing one or more sector-shaped chambers with a wiper rotatably mounted in the housing. For each chamber a paddle extends from the rotor of the wiper into the chamber. The wiper moves sealingly past the housing. For each paddle a bypass channel allows fluid on one side of the paddle to move to the other side of the paddle. A valve in the bypass channel controls the degree of damping produced by the stabilizer. The valve has a control shaft in the center of the rotor, and on the shaft there is a continuous indentation around such shaft with there being no indentation in a first area of the shaft and then the indentation commencing and having an increasingly larger cross-sectional area as the indentation progress around the control shaft.