With a rated output of 510hp and a peak of 583hp, Challenger’s MT865C sits just below the range-topping MT875C, making it comparable with the others tested here.
It is also the only tractor available designed from the outset as a rubber tracked machine, rather than one which has had its wheels replaced by belts and idlers.
For those who remember, 25 years have passed since the first Challenger 65 appeared - albeit with Caterpillar emblazoned across the bonnet.
On first impressions, the Challenger MT865C looks right - its squat, wide stance on 760mm (30in) belts makes it look fit for business. Put a dozer blade on the front and it looks as though it could remodel the landscape. It is the tractor equivalent of a prop-forward.
The Challenger has no fancy power boost or trick modes - just an 18.1-litre Cat six-cylinder engine, with just one turbo.
Grunt is its middle name, and such is the grin-inducing bark emanating from its exhaust stack, those outside the cab can hear it long before it comes into view.
It falls behind with 250-hour engine oil change intervals, and is one reason why Agco has recently announced an engine change, using its own Sisu Power on the new 700D series. Expect this to eventually filter through to the 800s.
Inside the cab, it is an altogether quieter affair. We found it not quite as quiet as the Quadtrac, but still a pleasant place to sit - once you have ducked in through the cab door without banging your head. That is because our test tractor had four optional sun blinds fitted, which are part of a £2,600 comfort pack.
One blind is fastened to the cab roof, in the doorway, which eats into headroom and acts as a scalping tool to the unwary.
The comfort pack also includes a leather-clad high-backed seat, sub-woofer under the passenger seat and four optional Xenon lights - two in the front grille and two at the rear.
Once seated, the grey and black interior is not as dull as you first expect, although it does not feel modern or bright, like the other two. We reckon the Challenger’s cab is its Achilles heel and is in need of updating. A bit of leather does not make it a premium environment either.
However, there is ample room to stretch legs and get comfortable. Angling the seat to help your view of the implement does give the cab a feeling of roominess and the steering wheel is easy to adjust.
A long bonnet makes it difficult to spot where the front of the MT ends, but in this respect, it is no different to the other two. However, it beats them hands-down with a platform around the cab so you can clean lights and windows without needing a cherry-picker.
The four-post cab offers a reasonable view all-round and there are plenty of mirrors. However, the steel bracket for carrying control boxes was just in the wrong place. There is no intermittent windscreen wiper control either and the climate control settings are awkwardly placed on the rear pillar.
That said, its armrest-mounted controls are conveniently laid out, with most falling to hand, including hydraulics, throttle and power management. Transmission functions are taken care of via a chunky direction lever, on which gear selection buttons are mounted. The lever also incorporates a park position.
Using this lever to engage drive does result in a sharp jolt, but it is designed to handle heavy loads.
Agco recommends only using the clutch pedal for hitching up and light manoeuvring to avoid premature clutch failure.
Any gear between first and 10th can be used to set off, and if you do get too greedy, anti-stall takes over.
Once up and running though, gear shifts are the smoothest and most responsive out of the trio, except when reversing. Be warned, there is an unnerving speed difference between third and fourth.
As well as monitoring performance, headland management is set up via the tractor’s own 180mm (7in) terminal. It takes a little bit of sussing out, but you soon get used to it.
Using a scroll wheel and short-cut keys to navigate, up to 35 functions per sequence can be pre-programmed and edited. There is no record function, but sequences can be played out as a whole or triggered in steps using the ‘one-touch’ rocker switch.
The terminal also handles the tractor’s power management system. Once a target speed is chosen and activated, the system manages engine revs and gear selection for optimum efficiency. It works well too, reacting quickly to changing conditions.
Like the Quadtrac and JD, the Challenger features a decelerator pedal to reduce the revs at headland turns. And like the others, we question why? There are plenty of other functions on-board which make the decelerator redundant, including two rpm settings, which can be pre-programmed and used in a headland management sequence, or chosen via a rocker switch.
Ours came with optional automatic steering, which can be accessed through a second terminal from TopCon (Agco’s preferred supplier).
This latest X30 touch-screen terminal is easy to fathom and has certainly tapped into the iPad generation, with icons depicting different functions.
In no time at all, implement dimensions can be inputted and saved for future use, and A-B or contour lines effortlessly set up.
Auto-steering can either be activated by touching an on-screen button, or by depressing a switch on the armrest - it automatically deactivates when the steering wheel is moved.
The X30 terminal can also be used as a virtual IsoBus controller for functions such as section control and variable rate applications.
On the down-side, having this large, second terminal in the cab does take up a fair bit of space, impeding slightly on forward visibility. However, it is a joy to use.
As a twin-track machine, you soon become acutely aware of ground disturbance when making headland turns. But heavy steering soon deters the scuffing - it needs a firm grasp to wrestle the Challenger on tight and twisty headlands, so you soon learn to turn gently.
GPS guidance also helps to alleviate scuffing as it lets you skip every other bout or every third, essentially taking a wider arc.
In dry, flat conditions, the MT865C feels unstoppable. Our test model was equipped with just over 4,000kg of additional ballast, helping those tracks to put that 3m-long wheelbase in firm contact with the ground.
Challenger’s hard bar system, which links the track frame with the chassis, complete with solid rubber blocks, does its best to keep the machine planted, while delivering a surprisingly comfortable ride - even at 40kph across a rutted field.
Yet it needs every kilo. Despite its 24-tonne operating weight, if you show the Challenger a steep slope, especially in our heavy Essex clay conditions, or worse suffer a shower of rain, it can fidget on the surface like a pike on the end of a fishing rod. However, unlike the Quadtrac, the MT can shed its weight for lighter duties.
Hitching implements on and off, albeit trailed, revealed the Challenger’s rear-end to be very user friendly - on a par, if not slightly better than the Quadtrac, and definitely way out in front of the Deere.
Spool valves are conveniently placed along with IsoBus and light sockets and power beyond couplings.
If you can justify it, the rear linkage is a £20,000 optional extra, adding another two tonnes to the rear of the tractor. A pto can also be fitted.
Most daily check points are convenient, with engine dipstick and coolant levels accessed off the main steps. Rear-end oil level is checked using a sight glass, but the tractor must be running.
What we like
What we dislike
FG ratings out of 10
Total (out of 100) 77