Height adjustment device

A motor vehicle's structure (MVS) (32) has its height adjusted by wheel suspension with a McPherson strut unit made up of a suspension spring (36) and a shock absorber (40). The suspension spring and the shock absorber are supported on the MVS by means of absorbing devices. The suspension spring's height can be adjusted in relation to the MVS by means of a hydraulic control element (10) with a sliding piston (14) fitted on the MVS.