The new Komatsu motor grader features several ergonomic upgrades

Komatsu motor grader

Komatsu America Corp is introducing a new motor grader equipped with new low-effort control levers, steering wheel and steering lever.

The GD655-7 motor grader is also equipped with a Tier 4 Final certified emissions regulations-compliant engine. The latest addition to the motor grader lineup will be sold concurrently with the current GD655-6 model to offer customers additional choices to meet their needs.

“The GD655-7 provides operators with an all new, ergonomic working environment and the new spacious cab allows more room for operators working long days” said Bruce Boebel, senior product manager for Komatsu America Corp. “Operators will appreciate the new low-effort equipment and steering levers, new transmission controls and articulation stop-at-centre feature. Collectively, they significantly reduce operator fatigue.”

In the cab

The machine’s new cab features a  slightly smaller, but “right sized,” steering wheel  designed to provide more visibility and room for the operator.

As well, the new steering lever allows the operator to keep hands on the low-effort, work equipment levers and make small steering adjustments while operating, without needing to turn the steering wheel. Furthermore, a new multi-position adjustable arm rests and LH/RH consoles have power raise/lower and mechanical fore/aft adjustments to precisely adjust to operator preferences.

The GD655-7 motor grader is also outfitted with a new high-capacity, air-suspension seat that softens in-cab machine vibrations; a new stop-at-centre articulation feature designed to simplify operation; and a new operator presence monitoring system that alerts the operator if they leave the seat and controls are not properly locked.

Under the hood

The GD655-7 motor grader is powered by a 218 hp Tier 4 Final certified, SAA6D107E-3 engine. IT is also equipped with 2-mode, 3-stage Variable Horsepower Control (VHPC) that allows the selection of the economy or power mode to match operating parameters to the application requirements for optimal fuel savings.

The Komatsu Diesel Particulate Filter (KDPF), and other after treatment components, are designed in conjunction with the engine for efficiency and long life.  More than 98 per cent of KDPF regeneration is performed passively, with no action required from the operator and no interference with machine operation.

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Komatsu also designed the new motor grader with several powertrain improvements, including:

  • A new transmission shift lever with finger-operated forward-neutral-reverse switch.
  • The Komatsu power shift transmission that provides on-the-go, full power shifting, as well as inching capability and automatic shifting in the higher ranges.
  • The industry exclusive dual-mode transmission (eight forward and four reverse) that allows operators to benefit from the high travel speeds and reduced fuel consumption of a direct drive, as well as the increased tractive effort and control of a torque converter
  • An inching pedal to provide precise control of machine movement.
  • Full locking differential to provide the traction required in severe operating conditions.

A closed-centre load sensing hydraulic system, with variable displacement pump, supplies flow and pressure only when required, resulting in less heat and lower fuel consumption is standard on the grader.

For protecting the moldboard, Komatsu included blade lift accumulators that absorb shocks when the moldboard hits immovable objects and a circle slip clutch for accidental contact with hidden objects with the moldboard.

Other standard features include two, five-section hydraulic control valves; greaseless circle wear plates for long life; an independent blade lift float; a 15 cm, full colour, high resolution monitor with Ecology Guidance and a separate, full colour, rearview monitoring system; and the Komtrax telematics system and monitor that provides various machine metrics, including KDPF status and DEF-level data and fuel consumption.


To simplify maintenance on the motor grader, Komatsu designed the machine with a reversible, variable speed hydraulic fan to blow out dust accumulation in the cooler as well as ground level access to fuel and DEF fill and accessible oil and coolant drains.

The grader also includes completely sealed and adjustment-free hydraulically actuated, wet, disc brakes.