THE fundamentals, first: the Allroad quattro suspension is a familiar four-link configuration at the front and a compact double wishbone set-up at the rear, with an anti-roll bar at each end. Where it really gets interesting is the use of electronically controlled pneumatic spring struts, which enable ground clearance to be varied by as much as 66mm. Four distinct ride heights between 142 and 208mm are at the driver's disposal and can be controlled either automatically or manually via a dash-panel control unit above the centre console. Basically, each wheel has a ride-height sensor that detects ground clearance and adjusts the relevant air spring strut separately until the optimum ride height is found.