Overview
A portal axle is an off-road vehicle suspension and drive technology in which the axle tube or the half-shaft is offset from – usually above – the center of the wheel hub and driving power is transferred to each wheel through a simple gearbox built onto each hub. It has two advantages over a non-offset axle: first, ground clearance is increased, particularly beneath the low-slung differential housing of the main axles; second, any hub reduction gearing allows the axle half shafts to deliver the same power but at reduced torque, which reduces load on the axle crown wheel and differential.