Has the new Claas Axion tractor got real class?
The Axion doesn’t quite qualify as the first “true” Claas tractor – that title belongs to last year’s updated Ares – but it’s certainly more in line with the German manufacturer’s typical style.
The new tractor range is bristling with sophisticated technology, including the most advanced non-CVT gearbox on the market and an in-cab computer that handles virtually every tractor function from hydraulics to headland turnaround.
Following the tradition of previous ex-Renault Claas tractors, the Axion uses the combination of a John Deere engine and the same Gima transmission/backend used on Massey Ferguson’s 6400 tractors.
In fact the 6.8-litre engine is the same as that used in Deere’s new 30-series tractors. The only difference being that the block in Claas tractors acts as a structural component, whereas John Deere mounts its power plants within a chassis.
These latest engines use four valves per cylinder, a variable output turbo, common-rail fuel injection and exhaust gas recirculation to meet Tier III emissions standards.
CLAAS AXION 820 |
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But the mid-range Axion 820 we got our hands on is a straight-talking 183hp tractor that can pump out a maximum of 193hp at 2000rpm.
No “intelligent” power-boost functions from this power-plant then.
Where the tractor does start to get a whole lot cleverer is in the driveline department.
The transmission used is a 24F x 24R, six-speed powershift with four powered range changes. Developed by MF/Claas partnership Gima, the Hexashift unit is the same basic gearbox as MF’s Dyna-6 but uses different control software.
Its operation is handled by the Cebis in-cab computer – borrowed from Lexion combines and top-spec Xerion tractors – and a stubby, square-edged lever on the right-hand arm-rest.
Hexashift has two operating modes – Transport and Work. Switching between the two is done by flicking a confusingly inconspicuous rocker-switch on the right-hand console, marked only with the symbol of a plough.
Running up the road in “Transport” mode, all that’s required is a gentle nudge of the lever and the gearbox makes one of its six powershift changes. Once it reaches the top-end of the gear range, the operator experiences a short pause as the computer feathers in a powered range change.
It certainly isn’t jerky and hardly unbalances the tractor, even with a six-furrow mounted plough swaying about over rural French roads.
But it’s in the field that the true benefits of the system come to light. Flick the switch to “Work” mode and hit the auto option as you drop the plough into work. This sets the transmission to run through its six powershift steps according to load and that’s where things start to get clever.
The engine speed threshold for up and down shifts can be altered to suit various tasks via the Cebis computer (see panel). In this instance a screen appears with a depiction of an analogue rev counter – a yellow band indicates the points at which the gearbox will shift up or down, according to engine load.
CEBRIS COMPUTER CONTROLS |
Engine, transmission, linkage, pto and spool-valve settings are accessed by scrolling through menus using a new thumbwheel dial and selected by giving it a push until it clicks. The opening menu screen – which replicates analogue dials for engine rpm, speed, fuel and temperature – is accessed by an escape button. These two controls form the basis of all Cebis operations and once familiar it’s a very easy system to use. Simplicity is obviously an area Claas has concentrated on: If a particular setting – spool-valve timing for example – needs altering, flicking the relevant spool valve paddle control will bring its particular icon upon on the colour screen. Pressing the Cebis “Direct-Access” button takes you straight to the right screen showing all of that spool-valve’s individual settings. |
It’s simple, intuitive stuff that isn’t as complicated as it sounds.
For ploughing we were aiming to run the tractor at about 1700rpm – the mid point between maximum torque and maximum power. So we chose to set the transmission up to shift up as revs rose above 1900rpm and to make a downshift when the engine dragged below 1500rpm.
The principle is great and we know it works well on Claas’ smaller Hexashift-equipped Ares models but unfortunately this early pre-production Axion had a software glitch that meant we couldn’t actually experience auto mode in the field.
Not deterred, we struggled on, having to make gear changes manually, albeit at the touch of a thumb.
The six powershift steps are smooth enough but it is in this type of work that it becomes clear that this isn’t a full powershift gearbox.
Because engine and transmission are both under heavy load for fieldwork, smooth range changes are not an option and in effect the computer performs the operation a driver’s left leg would usually undertake.
Giving the gear-lever a slightly heavier than usual clout pushes it past a detent and initiates a range change. To do this the tractor disengages the driveline, shifts up a range and then re-engages the clutch pack – an operation that appears to take three or four seconds.
With a plough in the ground the tractor comes to an abrupt halt before taking up power fairly smoothly once more. It’s not the most pleasant experience for the operator and one that’s all too easy to do unintentially as it doesn’t take much effort to knock the stubby lever through its detent.
FW VERDICT
Claas has set out to produce a tractor capable of competing with the likes of Deere and Fendt’s latest models, and to do that it has had to play a rapid game of catch-up.
A computer terminal and “intelligent” transmission weren’t going to provide the solution on their own. But combining this with a gutsy engine, proven cab suspension and a workspace the size of a Seat Leon family hatchback makes this a real driver’s tractor.
As we’ve said before, Claas’ Hexashift (and MF’s Dyna-6) gearbox is the closest you’ll get to a real stepless CVT without the associated cost and power loss of a hybrid hydrostatic/mechanical drive.
No longer a Renault in green, red and white livery, the Axion is quite clearly a true Claas product and when it arrives on UK soils at the start of next year, it has real potential to put the cat amongst the proverbial pigeons.
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