Universality is in its DNA.

Evenly, almost gently, the Unimog U 423 moves off – despite the heavy rail car on the coupling. Test weights are being transported. They are needed for the annual safety inspection of the single-link and double-link rocker slewing cranes on the north quay at Regensburg's western port. Heavy cargo is handled there around the clock – and the Unimog U 423 is an important part of ensuring everything runs smoothly.

Without the built-in torque converter clutch (WSK) – a hydrodynamic torque converter for heavy-duty operation that works without wear – smooth moving off with such high towing loads would not be possible. The Zagro rail guidance for road and rail operation is just one feature of the 231 hp Unimog U 423. The Unimog still has many more jobs to perform in the port.

The team at the Regensburg facility is glad to have the compact implement carrier as a reliable tool for routine maintenance and clearing operations. Covering an area of 175 hectares and over 30 kilometres of rail track, those are time-consuming jobs, and so efficient equipment is more than welcome.

Bayernhafen Regensburg is a leading river-borne freight handling centre in Bavaria. It is one of six locations alongside Aschaffenburg, Bamberg, Nuremberg, Roth and Passau. Its main benefits are its economically key geographical hub location and its efficient interlinking of water, rail and road transportation. The port handles some nine million tonnes of freight a year.

In the past in Regensburg, winter spreading and clearing operations could still be handled with a Unimog U 90 and wagon operations with a shunting locomotive, but work requiring an aerial work platform, cutting back the clearance profile, mowing or mulching usually meant rented equipment was brought in or contractors were hired. To be able to carry out the necessary work more efficiently, in 2015 Bayernhafen first considered procuring a multi-functional work vehicle based on a Unimog.

For the Regensburg site these considerations were finally put into practice. As Klaus Hohberger, a member of the management board and responsible for the entire technical division at Bayernhafen, explains: "The demands of a port are very diverse, so we need more than just standard equipment." Thus, during brainstorming the requirements specification filled up with necessary equipment for the many use cases: spreading and clearing in the winter months, mowing and mulching, and also frequent material transport. Last but not least, consideration was given to excavation and earthmoving work, which, thanks to an onboard crane and grab, would make it possible to load and transport cuttings, mulch or gravel.

To be prepared for the wide range of applications, the Unimog U 423 is, for example, equipped with a mechanical front power take-off shaft and the Unimog's typical multi-circuit hydraulic unit. The hydrostatic traction drive allows infinitely variable control of the working speed when mowing or cutting clearances while keeping the revs constant. "The combination of a torque converter clutch and a hydrostatic traction drive was not previously included in Daimler AG's standard portfolio," explains Manfred Plodeck, sales advisor at the local Unimog dealer Beutlhauser. That brought the team from CTT (Custom Tailored Trucks) into the picture.

Ultimately, the Wörth specialist team mastered the combination of torque converter clutch and hydrostat with flying colours. The blue Unimog U 423 has now been in service at Bayernhafen for over a year and, since receiving rail approval on site, may also be used with all mounted equipment within the port area. In August a special front-mounted boom mower with a coordinated mower head was added, making the Unimog even more valuable for Bayernhafen.

For Mercedes-Benz Special Trucks it ultimately meant having an interesting new combination in its portfolio. "We are pleased to have found partners in Daimler and Unimog general agent Beutlhauser who took on the challenge of designing a vehicle specifically tailored to our specification," explains Klaus Hohberger. "With this support, we were able to realise, in partnership, a vehicle that is certainly forward-looking for this vehicle category."