JCB’s flagship 8000-series Fastracs have undergone a revamp with new engines and control software.
Instead of the previous Cummins-powered 248hp unit used in the 8250, both the new 8280 and 8310 use six-pot Sisu power plants pumping out a maximum of 279hp and 306hp respectively. These are married to the same Fendt Vario CVT gearbox as used before, strengthening the company’s partnership with Agco (which owns both Sisu and Fendt).
In fact, the new Fastrac now has exactly the same driveline as Agco’s Valtra S-series and Massey Ferguson 8600 tractors but with all the control software developed in-house by JCB and the British manufacturer opting for a full-suspended chassis over a conventional stressed block design.
Like many other tractor manufacturers’ machines, the new engine uses AdBlue selective catalytic reduction (SCR) to meet the latest emissions rules. By moving to exhaust after-treatment, this has meant the power-plant can be run in its raw ‘dirty’ form to produce maximum power and torque.
As a result, JCB is claiming a 10% improvement in fuel consumption over the previous 8250. In addition, noise levels have apparently been brought down by 40%. At 60dBA, says JCB, the cab is now the quietest on the market – it certainly seemed that way after a brief drive.
Because of the new “dirty” engine’s improved low-end lugging characteristics (it’s reckoned to generate 15% more torque than the Cummins block used before), JCB’s engineers have been able to set the engine/transmission controller to keep engine revs in the field as close to 1500rpm as possible.
When in one of two auto settings, revs hover around the point of peak torque, helping to maximise performance while minimising the tractor’s thirst and bark.
The new software also allows the keen operator to alter far more settings than before such as engine droop (the amount revs will fall before the transmission ratio will alter), pto cruise speeds, etc
The company has also come up with a clever-but-simple system to help minimise wheelslip in heavy draft applications. Called Activ Traction, it monitors transmission loading, draft and wheelslip and when the tractor starts to scrabble reduces engine revs at the same time as upping transmission ratios. This is said to maintain forward speed while limiting wheelslip – a system only made possible with a stepless transmission.