Mercedes-Benz has taken the wraps off its all-new Arocs range of construction vehicles at a launch ceremony in Munich. The Arocs shares the DNA of the new Actros, but it has been beefed up where necessary to endure the rigours of construction, demolition, waste transfer, and anything that involves adverse conditions.
There are 16 power output levels across four different engines: 7.7, 10,7, 12.8 and 15.6 litres. Ranging from 238 bhp to 625 bhp, all powerplants are available as Euro 6. The BlueTec 6 engines are all in-line six-cylinder models with exhaust gas turbocharging and charge air cooling for high torque from little more than idle.
Of greatest interest is the 15.6-litre, which replaces the long-serving V8. Codenamed the OM473, its top output from launch of 625 bhp is substantial enough to meet most needs, but the question is whether this is just the starting point for the new flagship engine.
Loader & Grounder
There are two different types of Arocs chassis: the Loader and Grounder. The Loader has been designed to reduce unladen weight as much as possible – a refreshing and much-needed approach to a sector which has suffered ever-diminishing payloads in recent years. One truck of particular interest is the new 8×4 concrete mixer, which uses super-single rear tyres on widened rear axles to increase payload and has a kerb weight of 9250 kg. This means a payload of 8 m3. To begin with, the Loader version of the cement mixer chassis combines the lightweight 10.7-litre OM470 engine with the ClassicSpace S-cab. In addition, the standard double-driven axle with twin tyres is replaced with a single-tyred rear axle with 368/65 boots.
The Arocs Grounder is designed for operating in extremely difficult conditions, such as in quarries or on building sites. The chassis has a thickness of 9 mm, and off-road customers can choose from three all-wheel drive variants offering optimised traction for specific applications. The new Hydraulic Auxiliary Drive is designed for an occasional need for increased traction. Engageable hydrodynamically driven wheel hub motors drive the front axle, instead of mechanical drive shafts. The weight saving alone compared with permanent all-wheel drive for heavy-duty off-road use amounts to half a tonne.
Next up is engageable all-wheel drive, where the front axle is engaged via the transfer case when the vehicle is stationary. Permanent all-wheel drive for off-road use is the ultimate option for trucks operating in the most difficult
of terrain.
Turbo-compounding
One of the features of the new Mercedes-Benz OM473 engine is turbo-compound technology. Turbo-compounding uses a second turbine, connected in series after the exhaust gas turbo. It also makes use of the available pressure of the exhaust after flowing through the exhaust gas turbocharger to further increase performance. Turbo-compound technology increases the output of the OM473 by around 68 bhp. At the same time, Merc said a reduction in fuel consumption of around two per cent is achieved under high load.
Gearbox options
Mercedes-Benz is pushing its PowerShift 3 transmissions in the Arocs – it’s standard fit, and although you can order a nine- or 16-speed manual gearbox, it will cost you extra. The auto ’boxes have eight, 12 or 16 gears. Shift times are up to 20 per cent shorter compared with the previous PowerShift 2, and even up to 50 per cent shorter compared with the Telligent automatic transmission.
There is all sorts of electronic trickery to help keep the Arocs moving off road, including the rock-free function and an off-road mode. Drivers can also operate the automated transmission manually should they prefer. Merc is adamant the system is now a better option than a manual gearbox, but it looks like drivers would need training to get the best from the many systems on the truck.
Cabs & interiors
There are 14 cab variants available on the Arocs, from a 2.3 m short day cab to the enormous 2.5 m BigSpace version – which is ideal for spending a week on the road. In the past, the likes of tipper trucks were built tough, and built basic. So it’s a surprise to climb into the Arocs and find a luxurious, well-made interior very similar to that of the Actros.
This new design philosophy means you get a graphics-enabled 10.4 cm TFT colour display fitted as standard. A range of seats are also available, including one with a massage function which has seven individual air cushions. Finished in tasteful Anthracite, first impressions indicate this is a durable environment, but the button-heavy dash is complex and may take some getting used to.
First impressions
Rival manufacturers may well be wondering what they can do to match this three-pronged attack from Mercedes-Benz. The manufacturer now has the most comprehensive range of trucks on the market. There is no doubt the Arocs is an impressive range of products, and we are looking forward to taking one for a test drive.
It’s technological approach will win it some new friends in the construction sector, but it may also frighten a few off. This is very much a truck for the 21st century, and drivers will need training to ensure they get the best from the vehicles – especially if they are going to be using the new automated transmission. The new Actros has been an enormous success, and we will watch how the Arocs fares with interest.
caption: New Arocs in concrete mixer set-up
