The 8×4 with single front axle has a Tridem bogie rear suspension, of which the tag axle is hydraulically steered. The result is extreme manoeuvrability and an unprecedentedly small turning circle. So you spend less time stopping, turning and reversing, and more actually driving.
The Tridem bogie has more advantages too. The raised tag axle contributes to less wear on tyres and improved fuel consumption. Optimised rear axle pressure on every axle means better traction (thanks to air suspension). And you can adjust axle load distribution for even better traction.
When you’ve got a heavy (or high) front load – like a superstructure with a crane or concrete pump – the 8×4 with dual front axles and a driven bogie gives you the manoeuvrability you need.