Deere Brings Joysticks to Grader Control

By Larry Stewart, Executive Editor | September 28, 2010
Deere Brings Joysticks to Grader Control
John Deere Grade Pro control armrest (right side)

Levers (right to left) on the right-armrest console control blade lift (button: blade control on/off), wheel lean, draft-frame side shift, and the front lever controls articulation (button: return to straight).

John Deere G Series motor grader

The G Series offers a lot of choices: electronic or hydraulic controls; wheel or wheel-and-lever steering; Topcon or Trimble grade control; tandem or all-wheel drive; front, mid-mount or rear ripper/scarifier.

John Deere G Series motor grader right side service panel

Transmission, hydraulic and axle oil filters are grouped for ground-level access.

John Deere distinguishes its new electronically controlled Grade-Pro motor graders from the only competitive joystick controls — on Caterpillar's M-Series graders — by mimicking traditional control-lever layout, replacing hydraulic levers with armrest-mounted electronic joysticks. Another unique feature: Deere's G Series offers buyers a choice of either hydraulic or electronic levers.

Deere's Customer Advocate Groups (groups of customers consulted extensively on machine designs) wanted clearer sight lines to the moldboard and less demand for the operator to move around in the seat. The electro-hydraulic control scheme on the new G-Series Grade-Pro machines minimizes the center console and allows operators to adjust themselves into the optimum ergonomic position. They not only see more of what's going on at the blade but they stay fresh and alert longer. Arraying the electronic joysticks like conventional hydraulic levers means today's blade hands can quickly adapt to the new controls.

Lever steering is added to the moldboard sideshift joystick in the middle of the left console. Moving the stick fore and aft shifts the moldboard. Moving it left to right steers the front wheels. The steering wheel remains in all G graders and is always live. Operators can always steer with the wheel.

Buttons on the blade-lift joysticks activate the cross-slope feature and interact with automatic grade controls, if they're added to the machine. A button on the articulation stick activates automatic return-to-straight, that centers the rear frame. (See a video explanation of G-Series electronic controls.)

Cross slope comes with the G-Series electronic, Grade Pro package. Position sensors in the frame interface with the controller and allow you to key in the desired slope and maintain it with just one blade-lift lever. The cross-slope system also facilitates plug and play of Topcon and Trimble automatic grade control systems. Deere says the system will also be Leica-ready very soon. All of the control buttons for these systems are built into the blade control levers.

The graders are powered by Deere PowerTech Plus 9-liter, Tier-3 engines with variable horsepower. They're coupled to Deere transmission managed by Event-Based Shifting software. Rear axles feature automatic differential lock that engages on the roll. Three of the six new G-Series models — the 672G, 772G and 872G — have six-wheel drive with a precision mode for ultra-low-speed operations.

Deere engineered the G-Series graders with transmission, hydraulic and differential filters in a right-side bank for fast access. Sight gauges, dip sticks, fill ports, other daily maintenance and test ports items can be accessed from the ground behind left-side access doors. There's also ground-level fueling and a swing-out cool-on-demand automatic reversing fan standard on every model. NeverGrease pin joints mean a 56-percent reduction in greasing.

G-Series Quick Specs
    Tandem Drive     Six-Wheel Drive  
  670G 770G 870G 672G 772G 872G
*SAE; with push block and rear ripper
Max Net HP 185 230 255 195 245 275
Op. Weight (lb.)* 40,986 41,405 43,119 42,682 43,220 45,068
Moldboard Length 12′ 12′ 14′ 12′ 12′ 14′



At its demo grounds in Arizona, Deere demonstrated its motor graders' all-wheel-drive capabilities.