Scania recently released the uprated output version of the brand’s proven 13-litre, DC 13 166 in-line six-cylinder engine.
Previously topping out at 500hp/2250nm, a point at which for many operators, represents the lower end of practical horsepower ratings for B-double work.
Prior to Scania’s latest 540 hp 2700nm powerplant release, operators would need to step up to the 520 hp V8 engine if they wanted to opt for a bit more punch. For those in areas where steer axle weights can be of concern, stepping up to the V8 engine imposes an extra 300kg weight penalty directly over the front axle.
Scania is offering the new 540 hp engine in the mid-sized G-series cab and full-sized R-series cab range, both offering 75-tonne GCM ratings.
Big Rigs was invited to evaluate the new engine in an R-series B-double configuration from the company’s Prestons dealership in Sydney.
The test truck was hitched to a pair of curtain sided trailers loaded with concrete blocks to a GCM of 58.46-tonnes.
The test route would take in motorway conditions southbound on the Hume Highway to Suttons Forest and back,
returning via Narellan road, the Northern Road and Elizabeth Drive to take in fairly common operating scenarios for a truck of this type.
Having previously test driven the same type of combination with the 500hp engine version, driving from Kalgoorlie to Perth in WA when Scania debuted the New Generation models around the country in 2018, I was keen to experience the difference.
A few local road twists and turns saw the Scania quickly enter the motorway and quietly attain the posted 100km/h speed limit.
As with all previously tested New Generation trucks, vision comfort and NVH levels are well sorted. Spending your working day in these Euro workhorses is undeniably a refined experience.
The new engine seemed to be undeterred by the 58-tonne ballast it was tasked with moving. Reaching and maintaining road speed for the early part of the journey proved unchallenging.
For those familiar with the southbound run on the Hume Highway out of Sydney, it’s well known the real work kicks in from the Menangle River.
From there on in it is basically all uphill until reaching the summit of Skyline, a good test for any truck.
According to the power and torque curve charts for the new engine, power reaches the 500hp mark at 1300 rpm before climbing to 540 at 1800 rpm.
Maximum torque is available from the get-go at a very low 1000 rpm before dropping off substantially at 1300 rpm.
Where the engine will work at is determined by the transmission mode selected. The 12-speed AMT transmission features three modes to choose from, ECO, standard and power. I evaluated all three modes to gauge the best outcomes for performance and economy.
While it’s hard to gauge the best mode for economy over such a short test drive, it is easy to see the difference the different modes have on gear selection and overall performance.
While maximum torque is available at as low as 1000 rpm, I felt driving in ECO mode at this weight encouraged the transmission to upshift and subsequently down speed the engine to a point where road speed suffered adversely when it came to an incline.
This mode may be beneficial to fuel economy when lightly loaded or empty and the available torque can overcome the lesser weight resistance, but for my liking at this weight I steered away from the ECO mode.
With a final drive ratio of 3.42:1 on the test truck, the tacho registered 1350rpm at 100km/h, this placed the engine speed at a good position to provide enough torque to overcome small inclines without the need to downshift.
In fact, the engine would lug all the way down to below 1100 rpm without downshifting if you let it, however if you are at the beginning of a serious incline, the road speed lost by allowing this to happen is difficult to recover.
With the power mode selected the transmission would instigate downshifts at around 1300 rpm, which would see the tacho jump to 1700-1800 rpm and provide ample pulling power and speed retention.
Overall, I found the best performance was to be had in the 1300-1600 rpm range, offering a good mix of both power and torque.
With power mode selected the transmission did a great job of maintain speed on grades, preventing the selection of 12th gear, even if a small lift off the throttle was given.
The constant swapping of gears between top gear and one below on some AMT trucks I have experienced, robs valuable momentum which cannot be regained. The programming of the GRS0905R transmission excelled in this area.
The toughest climb on the road test route was “Skyline Hill”. I attacked it with gusto in power mode from the bottom at 100km/h. Holding the throttle pedal flat, downshifts took place at around 1400 rpm sending the engine speed back up to 1700 rpm, this continued until 8th gear had been selected (auto mode) at which point the truck found its groove to hold 8th gear all the way top the top. The minimum speed up that hill was 45km/h.
After turning around at Sutton Forest for the return run back to Sydney, the challenges vary for the truck.
After a few inclines before reaching the top of Skyline Hill once more, it is now time to benefit from the excellent retarder operation on the Scania.
Over-runs are easily managed with the use of the downhill descent control which selects the appropriate level of retarder operation, minimising service brake usage.
Once back in Sydney and venturing onto main arterial roads the Scania was best left in the std or power mode at this weight.
Negotiating traffic and stop/start conditions was reasonably effortless, moving the truck from a standing start within acceptable timeframes.
Upon returning the truck back to Scanias dealership the trip stats are as follows:
• Distance: 233km
• Average speed: 66km/h
• Average fuel consumption: 1.8km/l (36.8L/100km)
Scania promotional material quotes potential for fuel usage reductions of up to 2.5 per cent with the new engine.
As mentioned earlier, it’s difficult to gauge accurate fuel consumption figures from such a short test, while at the same time evaluating performance ability, but for the terrain covered, think 1.8 km/l is notable.