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Underneath the bonnet of the McCormick X7.650 Efficient sits a Tier 4i, six-cylinder 6.7-litre engine which was built by FPT. The engine is rated at 152hp, with a maximum power output of 160hp. Like its predecessors, the X7.650 features a cast chassis with shock-absorbing rubber mounts which support the engine. McCormick claims this helps to reduce noise and vibration levels within the cab. The company also says the optimised electronic fuel injection and the enhanced combustion efficiency, combined with the Selective Catalyst Reduction (SCR), allows the new engines to deliver increased horsepower while reducing fuel consumption.
The X7.650 is fitted with a ProDrive transmission, which is designed and built by ZF. This transmission has a total of 24 forward speeds divided over six ranges. In addition, the X7.650 is also fitted with a creeper box as standard for operations that require slower speeds.
The transmission also offers three driving modes. In manual mode the operator controls all the ranges and powershifts, in auto field mode the gearbox automatically selects the correct powershift and the operator controls the ranges, while in auto road mode the transmission is fully automatic.
These modes are selected by the auto power shifting (APS) button on the multi-controller and can be further customised via the dash computer to set various parameters, such as starting gear and shifting points based on engine speed parameters and load.
The transmission and back end are bought from ZF as a complete unit, which is then bolted to the engine. There is a five-brake disc configuration on each side. To improve efficiency and reduce drag, the amount of oil delivered to lubricate the brakes is cut from 30l/min to 8l/min when travelling over 13km/h. Once the brake pedal is pressed, the flow is then increased.
The transmission also uses a mix of being showered in oil and pressure-fed shafts rather than being immersed in a bath of oil to help reduce rolling resistance. The rear lift is electronically controlled with two 100mm hydraulic cylinders delivering a lifting capacity of 9,300kg. Hydraulic power is delivered by a closed-centre piston pump system that provides a flow rate of 123l/min, as well as having a separate 44l/min gear pump which is dedicated to the steering and auxiliary systems.
Suspension
Cab and independent front suspension is fitted as standard, with the front axle manufactured by Carraro. It has a steering angle sensor which disengages the differential lock when working in auto mode.
Up top, the cab is fitted with a hydraulic suspension system at the rear and is mounted in rubber bushings at the front. This combination of front and cab suspension works well travelling across rough terrain or at 40 km/h on the road. The X7.650 is also equipped with combined front and rear differential locks to reduce wheel slip and maximise traction.
The differentials are electronically controlled by the Auto Function, which engages or disengages both the differential lock and four-wheel drive during headland turns. McCormick claims that the 55° steering with 5,400mm turning radius makes this tractor very manoeuvrable.
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