First drive: Mercedes-Benz Arocs

Sometimes, when all the ducks line up, you take advantage of it.

I was travelling to the UK on a sad trip to comfort an aunt who had just lost her husband of 50-plus years. But a couple of weeks before we left, Mercedes-Benz in Europe released its new Actros 'tractor', as they are called in the Old Dart.

Mercedes-Benz Australia got busy. Its PR chief, David McCarthy, pulled in some favours, and I fronted up at the 'Benz headquarters in Milton Keynes, north of London, for an extended drive in the new Actros with a Brit trailer on the back, two years before it arrived in Oz.

The drive revealed a Mercedes-Benz that really had to be a part of the Aussie operation as soon as possible. Simon Woods was McCarthy's UK equivalent, but specialised in trucks, and he had just finalised the introduction of the model into northern Europe.

He was the man who had just arranged the licensing of a staggering 100 new model Actros prime movers as demos and put them out in the industry for evaluation with no strings attached.

According to Simon, one British operator previously stuck on a Swedish brand was saving 300 quid in fuel per round trip from Glasgow to southern Wales. Think of all the egg and chips a Pom could buy with that!

So getting re-acquainted recently with the new 'Benz here in Australia didn't take long. The version I was introduced to was the Arocs, a derivative designed and spec'd for extreme heavy-duty applications, such as construction work and road trains. It has heavier-duty components where it counts and transmission specs that reflect GCMs at the upper levels, right up to 170 tonnes.

The Arocs cab has a daunting presence – it's so high it needs five steps to climb on board. Any higher and it would need pressurising and a flashing roof light to warn off low-flying aircraft. That means the door is a very long slab and needs care in high winds.

Despite the long way to the top, the wide and sumptuous cab still has up to 2.13 metres of headroom between the seats. The seat adjustment is redesigned to allow finer increments, and the stand-up-straight steering column makes entry and exit a breeze.

The dash is far less cluttered. 'Benz has brought as many controls as possible onto the steering column or wheel, and what's left surrounds the driver well within arm's reach.

To enhance in-cab movement, the gear selector has shifted from the left-hand seat armrest to the right-hand side of the steering column. A smallish visual display screen between the two main gauges, which show engine revs and road speed, is managed via remote-control-like D-pad selectors on the steering wheel. The display is hooded and features a clear white-on-black text style that doesn't get difficult to see in glare. I couldn't test that in England – there's never any glare.

Off to the left and in the main instrument binnacle is the main TFT screen where audio and GPS data are available. Below that are the climate controls.

There will be a range of seat options on the Australian models that I hope will include the massage unit, which appears to have enough grunt to re-align your spinal column. All seats now feature an extra 40mm width for the global bigger-bums trend, so my pointy rear end was a bit lost.

There's a minimum of three power sockets around the cab for the ancillary stuff that drivers will install – more are apparently available on request.

Around the ceiling, instrument panel and footwell is a large array of interior lights that are claimed to cheer the mood. Overall, the Arocs cab gets top marks for liveability.

Arocs will allow Mercedes-Benz dealers to aim for a market segment they have been shy of for many years. To ensure they make a running start, the truck I drove was one of several evaluation units imported to place in real-time commercial applications for engineering durability and compatibility testing.

The truck had the most powerful version of the new in-line six-cylinder engine. I only had a single trailer behind me which, although fully loaded, meant nothing to the truck's 625hp and 3000Nm of torque.

'Benz claims the new unit uses AdBlue at a rate of between 2-3 per cent of diesel, compared to 5-6 per cent for the old V8s. As a result the factory has cut the AdBlue tank to just 60 litres. But it'll need bigger AdBlue and diesel tanks if 'Benz is serious about getting into the road train market.

For this test, with only one trailer instead of the multis the truck is designed for, I decided to give the new cruise control/speed limiter system and engine brake a workout, to see how much a driver could actually use the buttons instead of the pedals.

On the road to Hastings, east of Melbourne, I set the cruise to 95km/h. The new engine brake – a five-stage unit with 475kW maximum retardation – would help me negotiate the dozen or so roundabouts en-route without using the big discs. As with most other systems, when the engine brake is on, the cruise control disengages, but the Arocs is set up so that as soon as you release the engine brake, the cruise control resumes.

The engine brake selector was the key, so as soon as the rig had slowed to the best speed for each roundabout, I dabbed on the footbrake to disengage the engine brake, then used a whiff of throttle to idle around the turns. As soon as I was heading to the exit, I released the engine brake lever and the cruise control resumed control, accelerating back up to cruising speed.

Very smooth, very safe, and very economical.

The well-known Powershift AMT is in its latest generation in this Actros, and it does its own thing as well as any of them. The right-side steering column stalk allows easy manual intervention if you're smarter than the computer.

Despite the range of improvements to Benz's biggest, there are a couple of things I'd probably change if I could, and indeed may be changed during development.

Firstly, can we have a USB charge port please? Much better than adapters. The transmission calibration also needs a fiddle. On one intersection when I had to go in a hurry, I counted 2.5 seconds before the truck selected a gear and accelerated.

The engine brake/transmission communication also needs adjustment. On one reasonably heavy brake I hit the service brakes and grabbed stage five on the engine brake at the same time. The transmission spent all its time changing down through all the gears and never got a chance to actually apply the braking effect.

I'd also make the retarder standard on multiple trailer rigs. 'Benz thinks its new engine brake is enough, and although it's one of the best there's no substitute for the retarding power of a virtually wear-free hydraulic system on the transmission.

Apart from that, when this range completes testing and hits the market late next year, I would think Mercedes-Benz will rightly expect its dealers to have their best shot ever to earn the market share this product deserves.

Related reading:
'Benz reveals next-gen timeline
First drive: Mercedes-Benz Actros 2651

MERCEDES-BENZ AROCS SPECIFICATIONS
ENGINE: 15.6-litre in-line six-cylinder turbo-diesel
POWER: 625hp
TORQUE: 3000Nm
CONFIRGURATION: 6x4
GVM: 26,000kg
GCM: Up to 170,000kg
WHEELBASE: 3300mm
EMISSIONS: Euro 6
TRANSMISSION: Mercedes-Benz Powershift 3
AXLE RATION: 4.333:1
SERVICE BRAKES: Disc
AUX. BRAKE: High-performance engine brake
CAB: 2.5m-wide BigSpace
WEB: www.mercedes-benz.com.au