The John Deere 7810 equipped with Infinitely Variable Transmission (IVT) was at our farm for only a couple of hours, but in that time, we were able to try it on a few applications. We used it on a manure spreader, hauled loads of round bales with it, ran a deep ripper with it and hauled wagons of corn.
John Deere's IVT is a relatively simple system to understand and operate. Three different settings allow the operator to drive under different load and throttle scenarios. When running the PTO at a required high engine speed — when pulling a forage harvester, for example — the throttle can remain at high rpm without interacting with ground speed. In the Load Control Mode, when running a tillage implement, the engine rpm will adjust to the desired travel speed to adequately pull the implement without having to be wide open all the time. In the Economy Mode, when towing loads or traveling down the road, the engine will automatically adjust itself to the lowest rpm to still maintain desired ground speed.
It's not hard to believe that the added cost of the transmission could easily be paid for with fuel savings alone. While running a deep ripper, it seemed odd to maintain speed at less than full throttle. But all we had to do was set the desired speed, put the lever in motion and listen to the engine power up until we reached the desired speed and then idle back automatically to the desired cruising speed. The coordinated efforts required for an operator to throttle up and down, plus shift, make it nearly impossible to replicate what the IVT does automatically.
On the left side of the steering wheel, the transmission has a six-position lever for park, forward, reverse, neutral, power zero and scroll. The scroll position works well when pulling loads of corn and coming up to a stop sign. It puts the transmission into a locked position and does not allow the tractor to roll, but still allows easy acceleration when pulling away from the stopped position. The power zero position works especially well for loader work. In this position, the tractor won't roll and can be held in one spot while loader functions are operated before returning to forward or reverse.
Ergonomics of the IVT speed control lever are great. It's a very comfortable feel and fits a natural motion well. The dual-range speed control lever allows the operator to set two different desired travel speeds. By moving the lever to the most forward position in the first range, the lower preset speed will be reached. Moving the lever slightly to one side and then advancing through the second range allows the higher preset speed to be reached. A handy dial on the speed control lever also allows the operator to change the preset speeds.
If there's a downside at all, it's the fact that maximum road speed is only 25 to 26 mph. Also, when traveling in reverse, it takes a little getting used to the fact that moving the speed control lever further forward actually increases your speed in the opposite direction. That's probably a habit developed from years of running hydrostatic transmissions.
This was just a 7810 that we drove. The new 7020 series tractors will have the IVT available with the CommandARM console that was first available on the 8000 series tractors. Based on my experience with the IVT, my next tractor will definitely be equipped with it!