A 6x6 vehicle does not necessary sound like something practical and with plenty of space. Instead, you tend to think of the jungle, the desert and a striking exterior with a lot of metal and prominent headlights. You might even think of the Mercedes G63 AMG 6x6, but a Sprinter? Probably not. However, the Austrian off-road specialist, Oberaigner, writes its own rules and combines the capabilities of a three-axle vehicle with the spaciousness and versatility of a van. Allow us to introduce the Oberaigner Sprinter 6x6.
The 6x6 is produced in Rostock. In typical Sprinter style, it has an understated look. Seen from the outside, only the third axle and the slightly raised running gear give any hint of this van's unique capabilities. The Sprinter also remains true to its roots in the cockpit. Four additional switches control five differential locks and activate the off-road gear reduction.
The flat bed is driven by a powerful 6-cylinder diesel engine with 190 hp. The 5-speed automatic transmission ensures that the driver never has to take his attention of the difficult terrain. The three axles are powered by a permanent all-wheel drive. However, impressive engine performance was not the primary goal of Oberaigner's engineers. Instead, they aimed to create a durable and high-performance van platform that provides rescue forces, the fire service and forestry workers with everything they need to handle any weather and any obstacle in remote areas. That is why the Oberaigner 6x6 has a gross vehicle weight of seven tonnes. In total, that means an unladen weight of around three tonnes and space for a four tonne payload. As such, the Oberaigner tops the largest Sprinter 4x4 by around two tonnes.
The Austrian company made no compromises when outfitting the Sprinter to handle that much more load. The ladder frame which carries the engine, axles and transmission was reinforced along the sides with special metal parts. This makes it especially rigid and prevents any frame twisting from ever occurring. The asymmetrical double pendulum rear axle mounting is a patented design which enables the vehicle to handle even the most extreme torsion forces that might occur on off-road terrain. This is the solution to an old and familiar problem. Many 6x6 vehicles tend to suffer from understeering – a very uncomfortable and also dangerous characteristic. This is due to the weight distribution on the axles. If there is too much weight on the front axle, then the front wheels lose traction when cornering and "push" the vehicle toward the outside of the curve regardless of the steering. Firstly, the special pendulum axle provides permanent axle load compensation and thanks to the asymmetrical design, it also increases the load on the rear axle. That is why the Oberaigner 6x6 tends to turn around this axle as well. A beneficial side effect: this also reduces the turning circle which can be a major advantage in remote, steep-sided valleys.
If one of the Sprinter's wheels are raised or the vehicle needs additional traction when starting on an incline or on a slippery surface, then it is time to activate the switches.
Although the pendulum axle with long spring travel almost always keeps the Oberaigner's wheels on the ground, the van is also equipped to handle even the most difficult situations. If one of the Sprinter's wheels are raised or the vehicle needs additional traction when starting on an incline or on a slippery surface, then it is time to activate the switches. Two longitudinal differential locks and two rear axle locks can be activated. An optional lock for the front axle is also available. These locks prevent sudden increases in engine speed when a wheel with inadequate traction starts to spin. Instead, the torque is diverted to the other wheels. Specially developed software handles the activation. It prevents the locks from activating under unfavorable conditions such as at high speeds.
The differential locks are only one of the sophisticated technical features that Oberaigner has integrated into the Sprinter chassis. A specially developed ABS for the six driven wheels ensures that the Sprinter can still be steered when braking. The newly developed ABD (automatic brake differential) uses targeted braking to specifically prevent individual wheels from spinning. Yet if even the brake control systems and the differential locks are not enough to keep the vehicle moving, off-road gear reduction can also be activated. The off-road gear reduction increases the gear translation to 2.85:1. This means that 2.85 engine revolutions equal one wheel rotation. This short translation enables the vehicle to accelerate faster and also briefly increases the traction. An ingenious assistant on extremely loose surfaces.
The tires themselves are also designed to assist in any adventure. The three axles follow a single track and essentially pave their own way (multi-pass effect). This reduces the roll resistance and the slippage for the rear tires. In contrast to the Sprinter 4x4 (with a gross vehicle weight of five tonnes), the 6x6 is more efficient and has greater attraction thanks to its single tires. In addition, the space savings also increase the through-loading width.
Furthermore, the Sprinter can also be equipped with all of the bodies available for the standard Sprinter models from Mercedes-Benz. As such, the Oberaigner offers a total package that makes it truly unique among the 6×6 vehicles.
The technical sophistication of the Oberaigner 6x6 is remarkable. And the other features are also something to be proud of: An increased wading depth of 65 cm protects against unwanted water damage. Options such as raised engine air intakes, an underride guard on the front axle and the transfer gearbox or a cable winch at the front provide an almost infinite range of possibilities. Furthermore, the Sprinter can also be equipped with all of the bodies available for the standard Sprinter models from Mercedes-Benz. As such, the Oberaigner offers a total package that makes it truly unique among the 6x6 vehicles. It can be used wherever high payload, compact dimensions, outstanding traction and efficiency are required. That is why: the Sprinter 6x6 is at home all over the world.
original Mercedes-Benz frame reinforced by Oberaigner
6x6 all-wheel drive
5-speed automatic transmission, permanent all-wheel drive
519 CDI, 6-cylinder diesel engine
increased payload up to 4,000 kg
Permissible nose weight
max. 140 kg
140 kW (190 hp), 440 Nm
Technical maximum speed
100 km/h (electronically governed)
Ground clearance below the axles
unloaded: front 322 mm, rear 257 mm; loaded: front 256 mm, rear 257 mm