The new Cat® 6M3 motor grader features engineering enhancements that boost fuel economy, increase structural durability, simplify maintenance, add operator convenience and promote the safety of both the operator and those around the machine. It is available in configurations to meet engine emissions standards worldwide and is an essential machine to build and maintain mine haulage roads―to keep trucks running most efficiently and at the lowest cost per tonne of material moved. The 16M3 has a 4.9 m moldboard and an average operating weight of 32.4 t. The motor grader is optimally sized for operations using 136-t or smaller trucks.
The 16M3 features a Cat C13 ACERT™ engine with the Cat Optimized Variable-Horsepower system, which provides net power ratings from 216 to 259 kW. The engine is available in three configurations to satisfy global emissions standards: U.S. EPA Tier 4 Final/EU Stage IV/Japan 2014 (Tier 4 Final); Tier 3/Stage IIIA /Japan 2006 (Tier 3) equivalent; and Tier 2/Stage II/Japan 2001 (Tier 2) equivalent.
A new ECO mode, standard for Tier 2 equivalent and Tier 4 engines, is designed to improve fuel economy by optimising engine speed to 1,900 rpm in working gears when possible with no compromise in performance. This operator-selected feature delivers fuel savings estimated to be as much as 4 to 5%, compared with working in comparable light- to moderate-load applications with the system deactivated. An additional engine control system feature provides consistent power to the ground by continually adjusting the engine to compensate for power losses to the cooling fan.
Also new for the 6M3 is the “OK-to-Start” system, which automatically checks the engine coolant, engine oil and hydraulic oil levels when the key is turned to the on position. The system also monitors these levels and the trans-axle oil level during operation, and it alerts the operator if levels drop too low.
Drive train and structures
The Cat direct-drive, power-shift transmission, with eight forward and six reverse gears, incorporates the Cat Advanced Productivity Electronic Control Strategy (APECS) system, designed to smooth gear changes and promote productivity. The modular trans-axle now has a standard automatic differential lock, which ensures appropriate locking/unlocking for optimum traction and manoeuvring, thus averting possible damage from ill-timed manual control.
The 6M3 also features nearly 15% greater dynamic braking torque at the rear tandems, achieved by enlarging both the brake disc diameter and the piston area. A new manual brake wear indicator simplifies disc wear measurement, eliminating having to remove the brake pods to check wear.
The 6M3 front frame, hitch area, and rear frame have been specifically designed to ensure long-term durability with the added weight and power of the new model. The centre-shift section is now a heavy-duty steel casting designed to effectively distribute stress and enhance durability in this highly loaded area of the mainframe. The rear frame is lengthened, incorporating two bumper castings for added counterweight, and the hitch plates (at the articulation joint) are 50% thicker than those of the 16M. The longer frame improves machine balance and steering control and provides easier access for routine maintenance.
In the cab
The new full-colour touch-screen display, with an intuitive menu structure, allows the operator to monitor machine performance, set parameters to suit operating situations, and access service information for initial troubleshooting. The new display also shows Cat Grade Control Cross Slope readings and DEF (diesel exhaust fluid) level.
In addition, a new keypad with lighted, one-touch buttons replaces most of the three-position switches used previously, further easing the operator’s job. Advanced Control joysticks (a retrofit option) enhance control of the Cat Grade Control Cross Slope or AccuGrade™ systems and also have provision for auxiliary-hydraulic control.
Also standard for the 6M3 is the Caterpillar Vital Information Management System (VIMS™), which provides real-time information about machine health and surroundings, trends, events and other vital machine information to support production and planning.
Safety and service
The standard rear view camera system presents crisp images on the new information display or on an optional LCD screen above the rear view mirror. Also standard is a seat belt indicator, which alerts the operator that the belt is not fastened and records the incident as a fault code.
The optional enhanced-access platform provides ladders, walkways and handrails that allow access to the cab or engine compartment from either side of the machine. An available service access configuration has ladders, walkways and handrails for convenient access to the engine compartment from either side. Double doors provide open access to the engine and use stainless steel barrel hinges for easy removal. An available fire-suppression-ready package facilitates installation of most recommended fire-suppression systems suitable for the 6M3.
Key service intervals have been extended for the 6M3: engine air filter and pre-cleaners have twice the life, compared with the 16M, and service intervals for the main hydraulic, pilot and transmission filters have doubled from 500 hours to 1,000 hours when S•O•SSM sampling and Cat filters are used. In addition, transmission/rear-axle fluid-change intervals are extended from 1,000 hours to 2,000 hours with S•O•S sampling.
In the engine enclosure, clearance above the valve cover allows injectors, compression brakes and valves to be serviced without removing any major components. The modular design of the rear axle allows removing the final drives in-chassis, significantly decreasing service time.
The 16M3 also uses a new modular cooling package, which facilitates removal and installation of components in the cooling system, providing an estimated time saving of 20%, compared with the 16M. Clean-out doors provide easy access to the cooling cores.
A durable metallic fuel tank is modular in design and can be serviced with fast-fill fuel systems delivering up to 567.8 litres per minute. The new radiator shunt tank is fabricated of metal. On models equipped with a DEF tank it has been strategically positioned at ground level for easy filling when the fuel tank is being filled.