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Two years ago, Dennis Child was a specialist energy supplier who happened to enjoy taking pictures of interesting trucks in his spare time. Then came a phone call from the blue which saw him employed as general manager, operations of the specialist transport company Rotran.
This move gave him responsibility for arguably the best toy box in the road transport world. It currently includes three Tractomas 8x8s and four 10x10s, five 8x8s about to be delivered and another 10 8x8s due by 2011.
The specification of the Rotran fleet, which moves giant electrical distribution components around South Africa, differs from any European norm.
Tractors and trailers have to comply with complicated construction and use legislation. This extends to operational bureaucracy, with the fleet's longest journey of 1,200km involving the co-operation of 47 different officials, few of whom have any interest in the task. The heaviest load shifted so far has been a 414-tonne transformer, but 600 tonnes is being anticipated.
Dennis Child's latest toys are a batch of five Tractomas D75s 8x8 drawbar tractors, to which the finishing touches are currently being added at the Nicolas factory at Auxerre, some 100 miles south of Paris. Nicolas is a maker of some serious heavy haulage kit.
The spec is as impressive as you'd hope. The Cat C27 Acert engine is a 27-litre V12 four-stroke turbo-diesel, which delivers 951hp and 4,342Nm, weighing in at 2,946kg dry. The remote-mounted powershift transmission is from Clark (part of Dana-Spicer), gives eight forward and four reverse ratios, and is driven by a torque converter with manual lock-up. An integral hydraulic retarder is fitted, and two output flanges direct drive fore and aft. The 25-tonne rear axles are hydraulically suspended, while the 12.5-tonne front axles ride on a single large inverted semi-elliptic leaf spring on each side.
The cab is from the latest Renault Kerax, sitting in front of the 200-litre cooling module, a vital component given operating conditions ranging from -6° to 55°C, and from sea level to 1,900m. The accommodation module, which contains bunk-beds, a kitchen and shower, but no toilet, sits atop an 18-tonne steel ballast plate. A pair of 1,000-litre diesel tanks need refilling at the end of every day's 100km journey.
Although the trucks have been tested on French roads, the bureaucracy involved means there has to be a better reason for running them than giving journalists joyrides, so we were limited to the factory perimeter road.
While it may be the world's biggest road truck, it isn't the fastest. The Tractomas's normal operating speed is 10-15km/h; we had no trouble reaching its 25km/h maximum around the site.
Driving it solo couldn't be easier. The engine starts conventionally on the key, but the gearshift layout is far from conventional. From a central neutral position, the lever is moved right and forward for first. Second is further to the right, third is forward and fourth is to the left. You continue zig-zagging away forward until you reach eighth, while the four reverse gears are similarly laid out on the far side of neutral.
In automatic mode, selected by a rotary switch to the left of the steering column, the box will self-change up to the selected gear.
The trucks were due to have the automatic mode disabled to prevent the possibility of a convoy moving off with one tractor still in neutral, which can damage the transmission.
In manual mode, there is a separate button to press to lock the torque converter, which is done manually after each gearchange. While the trucks don't have to meet specific emissions targets, they're so much cleaner than the older Pacifics in the fleet that radios have to be used to monitor the other tractors in the train, rather than watching for smoke signals as they change gear.
Apart from the 3,600mm overall width, manoeuvring in confined spaces is surprisingly easy, helped by a good complement of mirrors. Only the front corners need careful monitoring. The most difficult part is avoiding pressing the accelerator pedal while braking, even with a delicate pair of size eights, while the brakes need a good shove.
While the Rotran fleet is already impressive, its forward orders with Nicolas get even better. As well as some 10x10 Tractomas D100s, its current portfolio will culminate in a new beam trailer in 2011. The 20-axle trailer will be 200m long, with a kerb weight of 560 tonnes, and with up to eight tractors, will run at 1,400 tonnes GCW.
Model: Nicolas Tractomas D75 8x8
Engine: Caterpillar C27 Acert 27-litre
Power ratings: 951hp @ 2,100rpm
Torque outputs: 4,342Nm @ 1,400rpm
Gearbox: Clark 16281 eight-speed powershift with torque converter and lock-up clutch
Brakes: Full-air system. Front, 500x180mm drums rear, 500x120mm drums
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