The two all-wheel-drive models offer six-wheel drive combined with four-wheel tandem drive and a front-wheel Creep Mode for precise fine grade operations. The operator has 16 selectable levels of aggression to match AWD performance to the task at hand.
Cat takes a major leap with controls
The most radical change in motor grader design can be found in Caterpillar's new M-Series lineup. More than 100 patent applications were filed with development of these machines, which include about 30% new content. The seven M-Series models will ultimately replace the 10 H-Series models, with initial release starting in the fourth quarter of this year and concluding in mid-2007.
The most significant changes can be found inside the cab. The M-Series replaces the traditional control setup — often consisting of as many as 15 levers and a steering wheel — with a joystick-operated, electro-hydraulic control system. Two three-axis, low-effort joysticks simplify control and reduce operator arm and hand movements by as much as 78%. The left joystick controls steering, articulation and fore and aft left blade lift and float. The right joystick controls fore and aft right blade lift and float, blade shift and circle turn. Both joysticks also incorporate buttons to control gear selection and other functions of the machine.
The new control system is designed to enable operators to sustain high levels of efficiency throughout the work day. The intuitive control pattern also makes training fast and simple for both new and experienced operators.
The changes in the control system have also opened up the interior of the cab, delivering significant improvements in lines of sight to the drawbar, circle and moldboard (DCM) and snow wing area. In addition, the cab doors are angled and the floor is tapered to provide unobstructed visibility to the front tires, heel and toe of the blade and DCM. The sloping, tapered engine enclosure further opens lines of sight to the ripper.
Cat C-Series Tier III engines with ACERT Technology power the new machines, delivering ratings from 125 to 500 hp. Variable horsepower (VHP) is now standard, with optional Variable Horsepower Plus.
All models except the 24M feature a direct-drive countershaft transmission. Electronic Clutch Pressure Control allows for smoother gear-to-gear and forward/reverse shifts, plus prolongs the life of drivetrain components.
An all-wheel-drive option delivers 42% more torque vs. the H-Series system. Dedicated left and right pumps allow independent control of hydraulic flow to each front wheel hydrostatic motor. To compensate for hydraulic power demand, the engine automatically delivers added horsepower to provide constant net power to the ground.
The all-wheel-drive system also features a front-wheel-only hydrostatic mode for precision low-speed performance. This mode provides infinite front wheel speed control from 0 to 5 mph.