Concepts and Reality: Volvo Fuel Super Truck

By: Steve Brooks


We put Volvo's slick Fuel Super Truck head to head with an off-the-shelf FH16 600 between Brisbane and Sydney - with revealing results

 

Volvo's "Fuel Super Truck" Concept

 

About two years ago, at an industry gathering in Melbourne, a senior Volvo executive discreetly showed me a text message on the condition I wouldn’t report anything ‘until something actually breaks cover’. The text read simply: ‘FH16 540’.

Up to that moment, we’d been deliberating the merits or otherwise of Volvo’s 13-litre D13 engine in top-weight line-haul B-doubles roles.

Without putting too fine a point on it, it was my contention that, while the peak 540hp (403kW) rating is undeniably appealing for many applications, the 13-litre (actually, it’s 12.8 litres) engine’s performance, fuel economy and longevity are seriously stretched in line-haul B-double roles at weights consistently at or above 60 tonnes. The obvious inference was that, sometimes, there’s no alternative to cubes.

Anyway, after plenty of verbal jousting, the text at least confirmed that Volvo was thinking along the same lines and, more to the point, that a 540hp version of the flagship 16-litre D16 engine was a possibility. In time! Even so, despite subsequent enquiries over the next year and more, Volvo insiders had next to nothing to say about a 540hp FH16, despite whispers that tests were happening.

Still, there was nothing definite and no sign that anything was about to ‘break cover’. Until, that is, a recent event at Brisbane’s Mt Cotton Training Centre where Volvo Group Australia’s (VGA) ‘Fuel Super Truck’ concept made an appearance with a 540hp version of the formidable D16 engine slotted under a carefully recrafted FH cab.

Better still, a week later, I was given first crack at steering the striking but somewhat overstated ‘Super Truck’ on a line-haul leg from Brisbane to Blacktown in Sydney’s western suburbs.

For the moment, though, the slippery Swede had to play second fiddle at Mt Cotton to the true mega-stars of the event: a couple of seriously heavy lifters stirring through the remarkable ultra-low crawler gear version of the automated I-shift transmission.

Digging Deep

Quite simply, this was an extraordinary demonstration of the ultra-low crawler gear’s abilities at gross weights of 130 and 203 tonnes, snaking around a section of the Mt Cotton facility, which included a grade of almost 9 per cent.

Not for a moment would I profess to know much, if anything, about the skills and techniques of oversize heavy haulage on public roads, outside occasional runs in the road train realm. In my estimation, the big boppers of heavy haulage are truly at the top of the most specialised and skilled fields in road transport. Nonetheless, the opportunity to steer each of these units alongside leading Volvo driver trainers Per Hansen and Paul Munro, and experience the deep-rooted capability of the transmission to allow hundreds of tonnes to be hauled uphill at snail’s pace with the engine ticking barely above idle was nothing short of phenomenal.

In effect, the introduction of crawler gears and, separately, the unique and potentially game-changing dual clutch system, are all part of Volvo’s major push in drivetrain development centred on the undeniable success of the I-shift automated transmission.

So important are these developments to VGA that the man acknowledged within Volvo as one of the fathers of I-shift, Ove Wikstrom, was flown in specifically for the crawler gear’s presentation at Mt Cotton. As he would explain, the latest ‘crawler gear’ version of I-shift has been specifically developed to provide vastly improved starting traction and provide the ability to drive at ultra-low speeds.

Critical Components

Simply stated, the main features are:

  • I-shift with crawler gears can drive as slow as 0.5 to 2km/h and has the ability to lift off from standstill at 325 tonnes
  • The transmission is available in direct-drive or overdrive, with one or two crawler gears, and can be specified with two extra reverse crawler ratios
  • The crawler gears are simply an addition to a regular I-shift gearbox, adding 12cm in length, and with several components made from higher strength materials to cope with the higher loads
  • In a direct-drive gearbox with one crawler gear, the deepest ratio is 19:1, or 17:1 in an overdrive gearbox. By comparison, the deepest ratio in a standard I-shift direct-drive gearbox is 15:1
  • In a gearbox with two crawler gears, the lowest ratio is 32:1 while the ratio of the lowest reverse gear is 37:1 in a direct-drive transmission
  • Crawler gears are available behind 13- and 16-litre Volvo engines in FM, FMX, FH and FH16 models

While time behind the wheel of each unit was by necessity limited to one carefully choreographed lap of a short section of the Mt Cotton facility, it was an incredible insight into how I-shift’s integral crawler gears can make seriously heavy haulage so smooth and effective.

The potential for so many forms of heavy haulage, from road trains to massive indivisible loads, is extraordinary.

Likewise, there can be little argument that a single crawler gear has significant benefit for a multitude of workloads, from line-haul B-double to heavy truck and dog, particularly on steep starts in creeping traffic. Or, for that matter, just crawling super-slow at night into a crowded dealership after an interstate trip in a one-of-a-kind truck with very limited ground clearance. A truck appropriately nicknamed ‘Astro’.

 

Head-to-head. Volvo's 'Fuel Super Truck' concept alongside its FH16 600 sibling. The fuel gain was close to 10 per cent for the truck nicknamed Astro

 

Slippin' Along

Designed by engineers within the secretive Volvo Group Trucks Technology (GTT) division based at VGA headquarters in Wacol (Queensland), supported by colleagues at the GTT network in Sweden, the so-called ‘Fuel Super Truck’ can lay claim to being the first B-double concept truck in the world.  

Ironically, the project started nearly two years ago, probably not long after I was shown that text message in Melbourne, and had its first public showing at Mt Cotton.

Obviously enough, the goal was to take an FH16 platform, albeit on a low 800mm chassis height, and create a combination able to deliver a genuine and notable gain in fuel efficiency over a standard equivalent that, in this case, pits the ‘Super Truck’ against a standard FH16 600.

Volvo says trials through southern Queensland and northern NSW returned a staggering 20 per cent improvement in fuel consumption over the standard 600. Importantly, components used for streamlining the aerodynamics of the outfit needed to be available from local sources, therefore making fuel gains achievable and available to the industry at large.

As Volvo fuel efficiency manager and former media commentator Matt Wood put it: "Our truck had to be as practical as possible. The result is a uniquely Australian combination, a B-double that could be loaded with 34 pallets and driven down an east coast highway."

With the view that aerodynamic research is a game of margins with no single ‘silver bullet’ when it comes to optimising airflow around a truck and trailer(s), Wacol engineers found plenty of places to tailor the Super Truck concept.

Work included removing non-essential external impediments to airflow, even down to deleting the badges on the sides of the cab, filling in gaps wherever practically possible around the front, sides and rear of the prime mover, installing purpose-built skirts around the truck and trailers, and optimising the powertrain and driveline to enhance fuel efficiency. Drivetrain developments include an overdrive I-shift with single crawler gear, feeding into a 3.09:1 rear axle ratio and putting power on the ground through Michelin X1 single-drive tyres, notching 100km/h with engine speed at a leisurely 1265rpm.

Curious Omission

Funny thing, though! Nowhere in Volvo’s material on the ‘Fuel Super Truck’ is the 540hp rating mentioned. Nothing!

The closest is a press statement credited to Clive Jones, Volvo’s newly appointed vice-president of sales, who says the Fuel Super Truck is "…specially engineered for Australian conditions with a fuel efficiency-optimised driveline.

"The good news for owners and operators looking to reduce fuel consumption," he continues, "is that the majority of features in the Volvo Fuel Super Truck are available for ordering now."

Yet right at this moment, it’s unclear whether the 540hp version of the 16-litre engine is one of those "majority of features" available now or if it’s still under trial.

Whatever, the opportunity to drive ‘Astro’ and sample the big bore 540’s abilities on a line-haul run at 62 tonnes was grabbed with both hands.

Best of all, perhaps, the concept truck would be running in company with a standard FH16 600 pulling a curtain-sided B-double set, in the highly capable hands of good mate and manipulator of all things mechanical, Matt Wood.

From any angle, there was certainly plenty of interest in seeing how the 540 not only compared in performance terms with the 600, but if the stunning fuel gains during Volvo’s trials would be replicated in a real-world run down the Pacific.

Admittedly, there were some notable differences between the two trucks other than Astro’s flash features.

The 600, for instance, was four tonnes lighter at 58 tonnes, ran a 3.4:1 final drive ratio to record 100km/h around 1,350 rpm, and had the benefit of 2,800Nm of torque compared to the 540’s 2,650Nm.

The standard truck also had an I-shift gear lever while Astro was a ‘fleet spec’, meaning the driver doesn’t get a stick or buttons to play with. What’s more, Woody’s wheels had more than 60,000km on the clock whereas its slippery sibling had just 10,000km under its belt.

 

Big bopper! Volvo's ultra-low crawler gear making ridiculously easy work of 203 tonnes at Mt Cotton. A remarkable evolution of the I-Shift transmission

 

In Practice

Leaving Volvo’s Brisbane South dealership in time for the morning mayhem on that carpark known as the Gold Coast Highway, it didn’t take too long for Astro to reveal a couple of distinct traits. Three, in particular.

One: the Michelin X1 single-drive tyres with their narrower track certainly have a pronounced and generally negative effect on handling, with the rear of the truck seemingly rolling outward, requiring regular correction at the wheel.

Two: the truck’s slippery nature, coupled with the low rolling resistance of single drive tyres and the low-friction properties of synthetic drivetrain oils, certainly verified early advice that the truck has a distinct desire to ‘bolt’ downhill.

On even the slightest grades, the propensity for quickly picking up speed was on occasion both remarkable and disturbing. On sharp southbound run-offs like Coolongolook, Moonee and Joll’s Bridge, early diligence was absolutely essential, especially without a gear selector to manually pull back a few gears on the approach. Together, these two factors made Astro one of the most challenging trucks I’ve driven in a long time, demanding constant attention to stay on the straight and narrow, and maintain a tight rein on any descent.

And three: the 16-litre 540 rating is a tenaciously willing performer. Despite hauling four tonnes more, it comfortably stayed in touch with its 600hp sibling on all but the longest climbs, notably the southbound run up from Hawkesury River, where the standard truck marched well ahead.

However, on the pull up to the St Helena tunnel, for example, the 540 dropped back to just ninth gear at 1400rpm, easily holding 50km/h. On the sharper climb up the northern side of Coolongolook, seventh gear was sufficient to hold 1400rpm and 35km/h. The runs up Ourimbah and Moonee were obviously tougher but, at full weight, the 540 certainly wasn’t shy, with the bigger bore showing a distinct desire to dig deep before swapping to a lower slot.

As for fuel, it was apparent by the time we’d crossed the border that Volvo’s ‘Super Fuel Truck’ was a dainty drinker and, by Kempsey, fuel was averaging a fraction less than 2.3km/litre, or just shy of 6.5mpg in the old measure.

However, with hills coming higher and more often on the second half, the overall average for the 890km trip had dropped only marginally, to 2.26km/litre, or 6.39mpg. Impressive, no doubt.

By comparison, the 600 ended the day at 2.04km/litre, or 5.75mpg; also impressive given the greater grunt and complete absence of aerodynamic add-ons.

All up, Volvo’s ‘Fuel Super Truck’ was just a fraction short of 10 per cent better on fuel. Sure, notably better in anyone’s book, but a long way short of 20 per cent better.

Questions and Queries

So here’s the thing: despite Volvo’s highly effective and commendable efforts in turning a standard FH16 B-double combination into a sleek, slippery concept capable of significantly enhanced fuel consumption, proponents need to ask if the gains are great enough to justify the additional cost and complexity of the complete package.

But arguably the greatest question of all is: when compared to the FH16 600, how much of the fuel improvement on this trip was due to aerodynamic and drivetrain developments, and how much to the 540hp version of the resolute 16-litre engine?

For now, it’s a question without an answer. Or at least, a public answer


Check out our video on the Australian winner of the Volvo Drivers' Fuel Challenge here


 

 

You can also follow our updates by joining our LinkedIn group or liking us on Facebook