MAN Truck & Bus


Heavy haulage with the MAN TGX


The haulage of large and heavy goods represents the supreme discipline in the transport world. A clear case for MAN’s introduction of its new truck generation to include the development of new heavy-duty tractor units to tow weights up to 250 tons and beyond. A demonstration vehicle from this new generation is now about to face the acid test: with over 370 tons in a push-pull traction unit.

A MAN TGX is loaded during the night.
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Around 7 o’clock on a Sunday morning: not an unusual time of day for oversized heavy haulage low-loaders. They need empty roads.

It is still pitch black and freezing cold at the agreed meeting point in mid-January. Shortly after seven o’clock and at minus seven degrees, three heavy haulage low-loaders with a total of five awesome MAN tractor units have assembled at the Dileb machine factory in Lebach, Saarland. Three of them are in the service of W. Mayer GmbH & Co. KG from Zweibrücken, all TGX 41.680 with V8 engines and decked out in the typical green company livery. The other two, equipped with 640 PS D38 in-line six-cylinder engines, also stand out visually: they have silver or bright red paintwork and belong to the demonstration fleet at MAN Truck & Bus – with one demonstration vehicle from the new TGX heavy haulage series in its première role as lead vehicle. “As part of the MAN Trucknology Roadshow, this vehicle is the first heavy haulage unit from the new TG generation”, clarifies Michael Makowsky, heavy haulage expert at MAN and responsible for the Trucknology Roadshow.

The convoy has been charged with transporting a pipe welding system to nearby Saarlouis, to the south quay in the Saar metropolis to be precise. Two equally impressive 500- and 750-ton mobile cranes are already waiting there to transfer the cargo onto a barge for onward transport to Antwerp. Yet this is a long way from being the ultimate destination: the assemblies are to leave the Belgian seaport to cross the pond and then travel further up the Mississippi towards Arkansas, USA.

Initially the stage to Saarlouis is on the agenda, however, and that in itself is no mean feat. A journey of 16 kilometres may sound like a piece of cake on paper. But the route along the “Saar heavy load section” features some aspects that make life difficult for even the most experienced haulier, including tree-lined avenues, low-hanging power lines, a few steep inclines, narrow roads through towns and some roundabouts. A challenge therefore, despite the fact that Mayer personnel have frequently travelled this route and know virtually every crash barrier by name. “The tricky spots are always somewhere different depending on the load”, comments Christian Lahm, technical director at Mayer, in retrospect. “This time it was the crossing to Henry-Ford-Strasse shortly before Saarlouis, and the exit from the Dileb premises right at the start. In each of these cases we had to work with a lot of lateral compensation and three tractor units.”

Deploying combined forces

In the aforementioned exit, sharply steep and what’s more with an interlocking carriageway, stands the 51.4-metre-long push-pull traction unit including the two powerful 640 PS D38 machines, by nature ready for the greatest challenge: the traction duo has to cope with the largest load in the convoy, being a section of the pipe welding system weighing around 233 tonnes placed on the 20-axle Scheuerle pendulum axle low-loader. The total mass amounts to 374 tons, and the high centre of gravity at over 7.30 metres (with a width of 5.30 metres) doesn’t make things any easier. Last but not least, the exit also has to be tackled in reverse to arrive on the adjacent main 269 road in the correct position ready to drive off in the direction of Saarlouis. After two unsuccessful attempts in the factory exit, the only option left was to add a third additionally coupled tractor unit to deploy the combined forces of almost 2000 PS to pull the low-loader into its starting position on the main road. Hans Dräger, an experienced driver for Mayer and this time at the wheel of the demonstration TGX, views the operation with the composure of a veteran. “It's certainly a bit different from delivering parcels. Never a dull moment.”

The subsequent wait on the tree-lined main road, on the other hand, is precautionary in nature: the advance team, including two cherry pickers in the convoy, is checking the avenue for overly low-hanging branches. Rainer Beyer, responsible for special and custom vehicles at MAN Truck & Bus Deutschland GmbH and on-board with Hans Dräger as a passenger, meanwhile gives some details for the record: “Enthusiasts will basically already know the demonstration vehicle’s drive train from previous TGX heavy haulage tractor units: 15.2-litre engine with 640 PS and 3000 Nm torque, reinforced cardan shaft with 36,000 Nm shear torque, 16-ton rear axles and ZF TCHD (torque converter heavy duty) with automated 12-speed MAN TipMatic 12.30 OD transmission and 440 torque converter clutch. We have a conversion factor of 1 to 1.58, in other words a breakaway torque of 4740 Nm. After hydrodynamic start-up, the converter is bypassed at 1200 revolutions and operation switches to dry clutch. Nothing new so far. What is new on the vehicle is the entire control system, for instance the newly configured software and heavy duty programming.” He sees its deployment at Mayer, a long-standing MAN customer and heavy load expert through and through, as a decisive development step – from practice for practice: “Until now the tractor unit has only driven in trials, so this is its first ‘real’ load journey. We will subsequently evaluate the data collected here in the road test and make further adjustments as necessary. There are also other such customer deployments in the coming months.” Although the basic configurations will by the way remain untouched. “Indeed the heavy haulage sector doesn’t want too many major changes”, Beyer knows from experience. “The frame, chassis, axle spacing – all that remains as usual. Customers therefore have advantage of being able to continue using their existing exemptions.”

The new MAN TGX has done well, this vehicle meets the heavy haulage requirements.

Christian Lahm
Technical director at W. Mayer GmbH & Co. KG

Two MAN TGXs and two mobile cranes reload the cargo at a port
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At the harbour: it takes two massive mobile cranes to transfer the load from the road onto the barge.

0 Litre-engine

with 640 PS and 3000 Nm torque


0 ton rear axles


Tremendous braking power

Colleague Steffen Richter, technical trainer for heavy haulage tractor units at MAN, also adds with regard to the push-pull traction unit: “We have essentially the same power train as in the silver ‘pusher’ from the previous generation, including the 600 kW Turbo-EVB engine brake and the Intarder 3 with up to 630 kW.” In combination, however, the tremendous braking power is limited to 980 kW to protect the drive train. Otherwise this could result in damage to the gearbox: “Nobody wants to see a gearbox breaking apart during the journey”, adds Richter.

Like Rainer Beyer, he also emphasises the excellent collaboration with Mayer. “We’ve been looking after this customer for many years and have been heavily engaged in this current deployment. This operation involves a constructive exchange for both parties.” As a technician through and through, however, he gets straight back to talking about the vehicles. “We do though have differences in the engine and transmission: the silver one is Euro 6C, whilst the new red one in version D3876LF10 meets Euro 6D and also has a slightly shorter gear ratio of 4.33 to one instead of 4.11.” A small but fine detail with regard to his pusher that Hans Dräger notices right from the first few metres: “I can tell straight away that my colleague at the back has different gear changing points due to the longer axle.” Given the close radio contact between the well-rehearsed team, however, this is only a question of coordination. “So put your foot down now, it’s getting steep” – they understand each other without many words.

As the convoy sets off again on the main 269 road, it is not only in full daylight, but the route is also lined with vast numbers of heavy haulage fans who are constantly filling their memory cards with snapshots. There is no need to rush, since progress is mainly at walking pace. Another completely new experience follows during the crawl through the community of Körprich with its 2000 inhabitants: passers-by wave in a friendly manner, children's eyes light up and even all the cyclists give way without complaint. That's something you don't usually experience in a load convoy... As things progress, even drivers wait patiently when the convoy goes the wrong way around roundabouts or takes up the entire opposite lane on ramps and bends. Although the conspicuous police presence is certainly another reason to refrain from sounding your car horn.

Happily at their destination

Meanwhile, what doesn't fit is made to fit: the advance team changes traffic lights and removes signs, the cherry pickers lift overhead lines and the police keep moving targets in check. The crossing of Henry-Ford-Strasse over a steep and frozen earth bank mentioned at the beginning of this article is ultimately only a question of time. Once again a third tractor unit is attached and then the route into the harbour is mostly a formality. “Always keep your foot off the accelerator at the bottlenecks ahead, unless I say differently. Just let yourself be pulled”, Hans Dräger calmly tells his pusher over the radio.

After almost five hours of transport, there is time for a first conclusion as the cranes load their cargo onto the barge. As he had done throughout the morning, driver Hans Dräger takes a relaxed view of the situation at the end. “I also have the automatic gearbox with torque converter in the V8, so it's easy to handle. Although manual intervention is never fully out of the question in heavy haulage operation. In terms of feel, the gear changes in the new one even are even smoother than in its predecessor; it is quieter than in the V8 and the braking power from the engine brake and retarder is very good. The all-round view and especially the mirrors are better now, and it’s really easy to manoeuvre. I would admittedly still like to test it over the mountains for a few weeks, but for now I can say: a little fine-tuning here and there, not much more.” Christian Lahm sees it similarly from a fleet perspective: “The new MAN has done well, this vehicle meets the requirements. We were already convinced by our predecessors with their V10 and V8 and the chassis and drive train technology quite simply suit this MAN. There will at some point have to be a replacement, but this new one with its D38 engine has already made a good impression.”

The final conclusion on this day is reserved for Arno Alt, managing director at haulage company Meyer: “We’re generally very pleased regarding our mutual exchange with MAN. We have competent technical contacts there and we can also rely on their workshops in Kaiserslautern and Sangerhausen. We’ve been driving MAN vehicles in the heavy haulage sector for decades now, and experience has shown that our suggestions from practice are taken up in new designs. For our part, we strongly involve our drivers in the decision-making process. Because our drivers are ultimately the ones who handle the material every day and can thus detect vehicles’ strengths and weaknesses.” 

Text   Ralf Becker
Photos   Björn Iversen

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