Scania’s Next Generation V8 R620 comes under the spotlight – Words by Brenton O’Connor – Images by Mark Bean
In developing the design of the Next Generation range of trucks, Scania has followed four key factors, concentrating on safety, fuel efficiency, driving enjoyment and uptime.
All major components of the trucks have been redesigned including cabs, engines, transmissions and suspensions, all aimed at improving these four demanding principles.
PowerTorque’s first drive experience on Australian roads was in the form of a Next Generation R620, with a fully laden run in B-double configuration from Scania’s Campbellfield dealership in Melbourne’s north through to the Sydney dealership at Prestons in Sydney’s west, via the Hume Freeway. The truck was coupled to a new set of curtainsider trailers loaded to a respectable (and verified) 61.5 tonnes for the test route.
Immediately noticeable about the new range is the cabin styling, which is certainly much different from that of the previous generation. The external appearance is more square, compared to the more rounded shape of the model it replaces. The sun visor is no longer a standard fitment, with Scania engineers stating the reason being to reduce aerodynamic drag for the effect it imposes on fuel economy. As a substitute, Scania has blacked out the top section of the windscreen to prevent glare from sun entering the top of the windscreen and affecting the driver’s visibility.
Scania’s chief driver trainer, Alan McDonald, provided an overview of the truck and the main functionality of the dashboard, prior to pointing the big rig north on the Hume highway.
There’s no doubt this is a V8, as, once the engine is started, it has the familiar burble of which only a V8 can boast. The sound is unique of course, but becomes particularly more noticeable when compared to the previous-generation truck and with the engine under load.
This V8 is completely different from the 620 hp V8 it replaces, with 16.4 litres in displacement producing 456 kW (620 hp) at 1900 rpm and 3000 Nm of torque from as low as 950 rpm through to 1400 rpm. The new engine runs a common-rail fuel injection system using Scania XPI extra high-pressure injection, rather than unit pump injectors as seen on the old V8.
The particular truck tested was a Euro 5 variant; however, the new range is available in either Euro 5 or Euro 6 emission reduction technologies from which the buyer can choose, dependent on their enthusiasm for reducing the amount of AdBlue used in the SCR (Selective Catalytic Reduction) process. Only the 730 hp Euro 6 will use EGR technology together with SCR, with the remaining engines in the V8 stable adding a particulate filter to the SCR process in order to reach Euro 6 emission standards. With no date yet mandated for the introduction of Euro 6 in Australia, selecting the Euro 6 option will give buyers the choice to stay with current standards, or to future-proof their fleet by selecting the higher standard and greater benefits from a reduction in AdBlue use and lower engine operating temperatures.
Immediately noticeable for any driver used to Scania is the change within the transmission. The GRSO905R is an overdriven gearbox, with 12 speeds, plus two crawler gears, combined with the Opticruise fully automated gear change. As per the previous model, the retarder is standard, as is the engine exhaust brake.
The new Scania gearbox features a lay brake that acts to both reduce gearshift times (by 48 percent) but also to provide better drivability.
Instead of using synchro rings to synchronise the different speeds of the countershaft and main shaft in the gearbox during gearshifts, Scania has moved to a layshaft brake like most conventional truck gearboxes. In addition to the aforementioned benefits of quicker and smoother shifting, this will further act to lengthen gearbox life, as synchronisers are a wearing part, which shortens transmission life.
On the road, the new gearbox is truly sensational, and the benefits explained by Scania are certainly noticeable, particularly through the faster gear shifting. Also most impressive is the gearbox’s ability to choose the right gear, and not to hunt back and forth between gears as seen in some other recent truck reviews.
I believe a lot of this improvement comes from Scania’s new integrated topography mapping, which is included in the new truck. What this technology does is help the truck to see (or imagine it sees) what is coming by way of hills and slopes.
A previously common complaint with all AMTs in heavy trucks has been their inability to see the hill coming and consequently upshifting at the bottom of the hill. This impression is then compounded by its inability to see the truck is approaching the top of the incline. Rather than maintaining the current gear, the AMT then downshifts, prior to realising it’s made a mistake, at which point it then returns to another upshift that can be followed by yet another downshift before upshifting again as it heads down the other side of the hill.
If there is a disadvantage during this procedure, it’s when the transmission lets the engine lug right back to 950 rpm up a steep incline before downshifting. Scania says the truck is programmed to do this to save fuel and maintain the in the peak torque band. However, it does feel as if the engine is labouring, and also it costs road speed, rather than downshifting earlier and keeping the revs up.
The results with the new-generation transmission were mind boggling, and, in addition to gear selection, the topography mapping also influenced the cruise control and the application of power.
When lugging up a hill, the engine would automatically ‘back off’ and coast up to the top, as the result of the truck having been programmed to expect that it had reached the summit and was in the final stage of the ascent, prior to rolling over the crown of the hill. Having crested the hill it re-established control, using the angle of the descent to re-establish the speed set previously on the cruise control.
Every small gain in fuel economy builds towards a major benefit, so rather than pulling up the hill at full horsepower, then requiring the engine brake/retarder almost immediately to reduce speed on the decent, the truck lets gravity do its thing, which both increases fuel saving while reducing brake wear through minimising service brake applications.
The combination of the cruise control and overspeed limiter (set to a minimum of 3.0 kilometres within each other) meant that the service brake was not required at all on the journey from Melbourne to Sydney. Throughout the drive the retarder would automatically reduce the speed of the B-double combination whenever it detected a speed overrun differential of 3.0 km over the cruise control limit.
For the trip from Melbourne to Sydney via the Hume Freeway, loaded at 61.5 tonnes, this Next Generation Euro 5 truck achieved an overall fuel average of 1.83 km/litre, recorded at an average speed of 77 km/hour. The other truck on the journey was a new generation G500, and despite having a lower power to weight and torque to weight ratio, surprisingly it was able to achieve a slightly higher average speed than the R620 V8.
The new truck certainly steers much better than the old model, as the ‘kick’ that could be felt through the steering wheel was not as noticeable as it had been in the previous model R620 evaluated by PowerTorque at the beginning of the year. Unfortunately, due to time constraints, we were not able to evaluate the next generation on rough country highways, having to stay with the relatively smooth surfaces of the Hume.
Interior fit and finish is first class, and a big step up from the old range. The way the door shuts is truly car-like. I found the steering wheel to be incredibly complicated, with heaps of buttons through which to control audio, phone, cruise control, overrun speed, and the in-dash menu system.
One thing I missed from the old truck was the ability to revert from standard cruise control to distronic cruise control using a button on the right of the dash – this now is done via menu selection of the central display, which is neither as quick nor as easy as with the previous model.
This truck is a huge improvement over the range it replaces, particularly when it comes to interior space and comfort, transmission operation and the improved gearshift speed. Exterior styling will be up to each individual’s personal taste, as it is certainly much different from that of its predecessor.
Alternative Viewpoint – Ed Higginson provides his comment on the R620
Compared to the G-model, the R is noticeably bigger with close to a flat floor, much taller lockers mounted above the windscreen with 324-litres of storage, plus you can order large cabinets above the bed with hanger rails instead of a top bunk.
As the R-series is seen as the premium highway spec, it also gets many more extras over the G. These options include two tall fridges that can be set at different temps, charger sockets in the lockers for items such as a microwave or TV, chargers above the bed, and carpet between the seats. The V8 also gets a smart badge on the rear of the cab wall that lights up at night, just so others know what lies beneath.
Two items that stands out on the R-series, and better than many other trucks on the market, are the inbuilt cab cooler that works off the truck’s aircon with the engine switched off, plus an extendable lower bed. When sitting on the bed, there is a foot pedal for each seat that, when pressed, enables both seats to be moved forward, and then you can lift a lever on the bed to simply slide it forward for a full width 1000 mm mattress that feels very comfortable.
The R620 was programmed to enable us to manually change from 12th, so we could change down higher in the torque curve at around 1200 rpm to keep the momentum over hills. This resulted in about a 20 km/h difference over the crest of some of the steeper hills and felt much more enjoyable.