Said to be one of the most significant developments in the firm’s history of Loadall production, JCB has created a brand new transmission concept. James Rickard finds out more at the launch of the Loadall AgriPro.

Combining elements of a hydrostatic transmission with those of a powershift, JCB has created a completely new transmission for its Loadall telehandlers.

Called DualTech VT, the new transmission will be available in the manufacturer’s new range of AgriPro Loadalls, premium machines which sit at the top of the firm’s range. Three models make up the range (see panel), all with a 7m reach and powered by the firm’s own 145hp EcoMax engines.

DualTech VT is the culmination of a six year development programme and 10,000 hours of ‘real world’ testing in various conditions and jobs, says the manufacturer.

JCB_LOADALL_AGRIPRO-1030010_Main

Two transmissions in one; the hydrostatic element of DualTech VT comes courtesy of Bosch Rexroth, while the powershift part is JCB’s own.

But why the need for a new transmission concept? According to JCB, on average, telehandlers are used 60 per cent of the time for handling work, 35 per cent for towing and road work, and idle for the remaining 5 per cent of the time.

And it is those first two scenarios which provide the biggest conundrum for telehandler buyers; do you go for a torque convertor/powershift machine which provides good speed and towing capacity, or do you go for a hydrostatic machine which gives good pushing ability at slow speeds and precise speed control? Whichever option you choose, it is nearly always a compromise, particularly for sprawling farms which have expanded to multiple units and require a machine for road and handling work.

TRANSMISSION

JCB_LOADALL_AGRIPRO-1030004_Main

So how does it work? DualTech VT is essentially two transmissions in one; a hydrostatic module, which offers infinitely variable speed selection from 0-19kph, takes care of low speed handling work, after which, a three-speed powershift module takes over to propel the AgriPro up to 40kph.

Everything is done automatically, from the transition between hydro and powershift modules to the powershift changes. No torque converter is used in the powershift portion of the transmission, using clutch packs-only to change gears, providing direct drive to the wheels.

Speed can effectively be limited by selecting the ‘top’ gear which you do not want to go beyond. For example, keeping the machine in hydro drive will see a top speed of 19kph not exceeded, while the first powershift selected will see speeds of about 25kph reached, second shift 32kph and top gear sees the full 40kph realized.

FLEXIMODE

JCB_LOADALL_AGRIPRO-1030111_Main

Further transmission tailoring can be achieved using a system called Fleximode, which allows independent control of ground speed and engine rpm.

Once Fleximode is selected, you can manually set the engine revs with a hand throttle and set the maximum ground speed via a dial. The latter is shown as a percentage on the dash, which represents a percentage of the speed between 0-19kph, as Fleximode only works with the hydrostatic module.

When all is set and activated, it is a simple case of regulating ground speed with the right hand pedal. It is a straightforward system to set and one of the most intuitive on the market thanks to quick shortcuts and clear readouts on the dash. Also, when Fleximode is reactivated it will remember previous settings used.

IN PRACTICE

JCB_LOADALL_AGRIPRO-1030178_MainSeveral tasks, including handling, powering attachments and roading, gave us the opportunity to try out the AgriPro Loadall, in particular its DualTech VT transmission and various driving modes.

For handling, in this case loading a spreader, we kicked off operating the telehandler via conventional methods, i.e., managing ground speed and engine revs manually as you normally would with a hydrostatic machine. This means balancing throttle with your right foot to keep up hydraulic performance, and feathering the combined inching/brake pedal with your left foot to manage/limit ground speed.

This pretty much felt like driving any other hydro machine, albeit a very good one. However, flick into Fleximode and the whole experience is changed. With engine revs kept at a constant, which in turn keeps up hydraulic performance, all you then have to do is manage ground speed using just the right pedal, with no need to ‘bleed’ speed off with the inching pedal, or manage revs.

It was an unexpected and surprisingly good way of loading – certainly suited for short loading cycles.

JCB_LOADALL_AGRIPRO-1030182_Main

As well as benefits over conventional hydrostatic machine control methods, compared to a torque convertor there is also none of that fighting or manual de-clutching with/of the transmission.

However, Fleximode really comes into its own when using powered attachments, highlighted by the use of a yard sweeper. On top of setting revs and travel speed limit, oil flow to the third service can also be set.

By setting up the machine to match the attachment or job, it allows you to concentrate more on just controlling ground speed and the job at hand – ideal for feeding and bedding duties.

JCB_LOADALL_AGRIPRO-8_MainAway from the yard, a road run revealed a good burst of acceleration from the hydrostatic module followed by an almost imperceivable transition into the powershift element of the transmission. Subsequent powershift changes were swift and smooth, with speed progression feeling linear from 0-40kph.

Deceleration is just as impressive with the transmission tuned to offer a good amount of engine braking. The transmission will also skip gears, depending on rate of deceleration.

And nothing can prepare you for the almost savagery, in a good way, of the brakes which will stop the machine on a dime.

In addition, automatic or full time four wheel drive can be selected, with four wheel drive automatically disengaging when speeds above 19kph are reached.

HYDRAULICS

JCB_LOADALL_AGRIPRO-1030172_Main

It is not just about the transmission, the AgriPro Loadalls also get the latest updates as previewed at last year’s Agritechnica show. This includes the firm’s Smart Hydraulics package which features a 140l/min hydraulic piston pump, of which, 110l/min is available through the auxiliary service, regenerative hydraulics, boom end dampening, automatic boom suspension activation/deactivation, auxiliary venting and a bucket control system.

Suffice to say, loader actions are swift. Regenerative hydraulics, which affect boom lowering and boom retraction, also help cycle times by sending oil directly from one side of the ram to the other, rather than having to be sent through the whole system. It means less effort for the machine and it does not require any extra engine revs to work faster.

As for the bucket control system, this provides automatic shaking of the bucket or other attachment, which gets progressively more aggressive the more you move the joystick. It is a handy and effective feature for shaking off sticky material, but one which was only introduced because of lethargic fly by wire controls.

For more comfort and convenience, joystick control is now mounted on the seat, allowing it to move with the operator.

ENGINE

JCB_LOADALL_AGRIPRO-1030106_Main

Using selective catalytic reduction and external exhaust gas recirculation, all JCB Loadalls now meet Stage 4 emission standards.

Having planned the migration to cleaner emissions for a while, JCB has managed to lose the large, obtrusive diesel oxidation catalyst, which once stuck out the rear of the engine bay, and brought the whole clean-up system under the bonnet. Bonnet dimensions do not change, and visibility to the right rear corner is improved.

Depending on type of work, the manufacturer says for every 100 litres of fuel used, the Loadalls will use about three to six litres of diesel exhaust fluid.

Driving styles and conditions can also be catered for by selecting either Power or Eco modes. Power mode provides maximum machine productivity with quite aggressive characteristics including ‘holding’ onto gears longer before changing up, while Eco mode limits engine revs to 1,700rpm and sort of ‘softens’ everything up for a more relaxed, unrushed way of operating.

FG INSIGHT VERDICT

JCB_LOADALL_AGRIPRO-1030152_Main

Apart from a slightly altered roof line and AgriPro branding, the new telehandlers are almost indistinguishable from the current range of Loadalls. However, it is what is underneath which counts, and the new transmission is one clever piece of engineering.

Is DualTech VT a revolution? Maybe not quite, but the concept transforms a telehandler’s capabilities. If the aim of the game was to bring together the best of both worlds, then the manufacturer has definitely done it.

In addition, Fleximode allows tailoring of the machine to specific attachments and jobs making tasks much easier to carry out with less effort.

No plans have been revealed yet as to whether the new transmission will be used in other Loadall models or other JCB handling machines, but there certainly is further scope for the use of DualTech VT across the firm’s portfolio.

Production of the AgriPro Loadalls start in May, with prices to be confirmed.

BY JAMES RICKARD

Source: fginsight.com

AGRIPRO LOADALL SPECIFICATIONS

JCB_LOADALL_AGRIPRO-1030088_Main JCB_LOADALL_AGRIPRO-1030156_Main

Model 531-70 536-70 541-70
Engine JCB EcoMax EU Stage 4
Size 4.8-litre
Power 145hp
Transmission DualTech VT combined hydrostatic/powershift
Lift height 7.0m 7.0m 7.0m
Lift capacity – maximum 3,100kg 3,600kg 4,100kg
Lift capacity – to full height 2,400kg 2,250kg 2,250kg
Forward reach 3.7m 3.7m 3.7m
Forward reach lift 1,250kg 1,350kg 1,500kg
Overall height 2.49m 2.49m 2.49m
Width* 2.36m 2.36m 2.36m
Length** 4.99m 4.99m 4.99m
Weight 6,900kg 7,800kg 7,800kg
Hydraulics – main 140-litre/min Load Sensing
Hydraulics – auxiliary 110-litre/min
Note: * over tyres. ** to implement carriage, boom lowered.

Let's finish your next project together! Find out how we can help you.
e.g. Lattice Boom Cranes for Sale and Rent