In the US, Volvo launch a conventional model and for Diesel News’ US correspondent it was a chance to get some road test miles in a VNL 740 and the flagship VNL 860 – both with the new Volvo 13-litre turbocompound engine and the newly released, extra-tall final gear ratio of 2.47 to one. With the overdrive iShift automated transmission, this equates to extreme downspeeding, with the ability to cruise between 1,000 and 1,100rpm at 60 to 65mph (100 km/h), right on the fuel curve’s sweetest spot.
There was no opportunity to verify fuel economy, but Volvo says that this setup will gain 6.5 per cent fuel savings over the 2014 13-litre VNL, already one of the more frugal heavy trucks.
The test route gave us a combination of interstate, divided state highways and two-lane rural roads over a nearly 70-mile loop. Trailers – a flatbed with concrete blocks on the 740 and a van on the 860 – were loaded, with the trucks grossed out at around 77,000 pounds (36 tonnes) – a real test to the new turbocompound engines.
The number designation indicates roof height and sleeper size – the 740 dictates a mid-roof (40) and 70-inch sleeper; the 860 has a nominal 80-inch sleeper with the taller roof (60). Other trucks available but not driven were the VNL 760 (high-roof) and 300 (day cab) models.
The 740 is the equivalent to and replaces the earlier VNL premium mid-roof model. The 860 is Volvo’s new top-of-the-line model. Here, it was in Globetrotter trim, the new premium level that has the most comfortable and attractive interior. It also features external brightwork and has the Globetrotter name emblazoned across the sun visor for drivers to show they have the premium model in the VNL lineup. Because the 860 has the biggest sleeper it also carries the XL designation up there as well.
Both trucks featured the turbocompound 13-litre engine. This D13 TC is available in two ratings: 425hp with 1,750/1,450 lb ft peak torque, which was the engine powering the 740; and 455hp and 1,850/1,550 lb ft powering the 860. Both make their torque all the way back to 900rpm, which is absolutely amazing, since this is only about 300rpm above idle. However, the tall final drive gear of 2.47 with the overdrive 12th of 0.78-to-one means an incredibly tall 1.92 overall top gear ratio. This is extreme downspeeding, and with tires on these trucks turning around 500 revs per mile, it calculates out to 970 to 1,000 engine rpms at 60mph (96 km/h). So low-speed torque is all important.
The turbocompounding that boosts the low-speed torque uses a two-stage turbocharger where the second stage extracts additional horsepower from the exhaust waste heat and, because it is coupled to the flywheel, adds around 50hp that would otherwise be wasted up the exhaust stack.
On The Road – VNL 740
The new VNLs are so fully featured that before setting out we took time to review the controls, especially those on the steering wheel that control the driver display, cruise control, phone, stereo and a good deal else. In fact, there can be up to 21 buttons on the wheel, all there to keep the driver’s hands where they should be – on the wheel.
Similarly, we reviewed the iShift transmission shifter, a small stick mounted to the seat. There is an option for a dash-mounted button shift selector, which would likely make the access back to the sleeper a little easier – not that it is particularly awkward to get around the stick shifter. The seat-mount shift pattern is maybe counter intuitive, since you shift the lever back to select drive and forward to select reverse. But this is deliberate as it matches an automatic car’s shifter pattern.
There is no ‘park’ position – you shift to neutral when not in drive or reverse. There’s a ‘manual’ position, where the driver can select preferred gears using the shift knob’s side buttons, but you’d be crazy to think you’re smarter than the combined engine/transmission controller.
From there we picked up ‘drive’, released the brakes and eased out from Volvo’s HQ campus. It was then that the quite astounding new features of the totally revamped Volvo range could be appreciated. But while the driver accommodations, new, more spacious interiors and exterior styling are truly a step ahead, what became quickly apparent in the more recent ride ‘n’ drive is the enhanced steering of the new models. And, yes, the performance of the Volvo 13-litre, turbocompound engine.
In this evolution of the Volvo lineup, a front-axle stabiliser is incorporated into the front suspension. It was not mentioned at the July reveal and was not obvious on the test track. But out on the highway, the benefits of this simple upgrade were quite remarkable. The simple roll-control stabiliser/sway-bar imparts a far better on-centre performance, with the virtual elimination of any wander. There’s no sawing at the wheel to go straight down the road. It also virtually eliminated sensitivity to rough roads and road ruts and provided more precision in turning into a curve that allows a driver to ease through.
The Volvo label for this development is ‘Precision Perfect’ and it’s very appropriate. Also, by restricting chassis roll, the stabiliser bar makes the in-cab ride so much better, with less unrestricted cab excursion through a bumpy or undulating curve. And the turbocompound 425 in the 760 we tried in the morning session pulled like a steam locomotive from the moment we turned out of the staging area.
From the Volvo campus, it’s a short drive to join I-40 eastbound, and Peter Blonde – Volvo’s Senior Product Marketing Manager – Fuel & Transportation Efficiency – and I chatted completely normally in the uncannily quiet interior. Accelerating on the I-40 on ramp using full pedal, the engine would rev to around 1,300–1,400rpms then the iShift would pick up the next gear and drop onto 1,000rpm. It was all very relaxed. Then we entered a relatively challenging climb in the first few minutes that the TC engine completed in 11th gear. As we cruised down the back side of the climb, the transmission shifted into 12th and the rpms dropped back to a shade under 1,000 for our 60mph cruise at this point. And this was the 740 with the lower-rated TC engine. It was all so effortless and, because the rpms were so low, it was with minimal additional noise over the truck at idle.
In fact, at cruise with the adaptive cruise control doing all the work, the only sound was a little wind and road noise from the tires. Yes, there is a mild rumble but the turbocompounding and the aftertreatment all do their part to quieten the engine. The fuel injection is multi-event, so there’s way less diesel knock and the new floor covering does a masterful job of blanketing engine noise.
With the engine and transmission handling the chores, we were able to look out and enjoy the North Carolina scenery, an easy task given the revised hood, which has been lowered and fits tight around the engine’s cooling package. It also slopes off to the sides so the view to the road surface and the three-quarter view to the sides all add up to great forward visibility. The door mirrors are rigid and give an excellent view to the rear with forward wide-angle mirrors on the hood providing an additional safety margin for spotting traffic that may have crept into the blind spots beside the cab.
And should a lane-change be attempted without proper care, a warning buzzer sound and light on the A-pillar flashes to let the driver know there’s a vehicle there.
On The Road – VNL 860
The Globetrotter package includes some bright orange stitching to highlight the otherwise black interior. The seats – there are seven different models available – were the top-of-the-line, and while the drive only lasted about 1.5 hours, they certainly impressed with their comfort and range of adjustment.
The slight extra wheelbase and a far less harsh riding trailer gave the Globetrotter XL 860 a boulevard ride. The same excellent steering and ride characteristics we had noted in the 740 were apparent again – Volvo’s efforts to make the new VNL a driver’s truck have achieved the desired result.
As earlier, we enjoyed the effortless way the TC engine propelled us along despite the unbelievably low rpms, just hanging in there on the grades, topping out some with the tach approaching 900rpm before a downshift was made.
Regrettably, we had to return the 860 to Volvo’s campus when we could easily have driven back to California, enjoying every last minute in quiet, relaxed comfort. The new VNL truly is a driver’s truck, but there’s a whole lot more going on under the surface that should make it popular with fleets for its uptime, safety and a sleek appearance that shouts success.