Caterpillar has brought back its 651 Wheel Tractor Scraper with a bunch of changes, advancements and development comprising a new powertrain, controls, hydraulics and structure.

This single-engine model provides 44 cubic yards of heaped capacity and a 52-ton rated load. It additionally shares the same bowl design and many features as the Cat 657, permitting contractors with mixed fleets to stock fewer repair parts and lower owning prices. It substitutes the 651E self-propelled scraper, which Cat stopped nearly 15 years back.

A 629-horsepower Cat C18 engine powers the redesigned 651, which can touch speeds up to 34.8 mph. When paired with a push assist from a Cat D10 or D11 dozer, and its eight-speed transmission, the 651 can load with ease even in abrasive or rocky conditions.

The scraper’s new Advanced Productivity Electronic Control System combines the transmission and engine drivetrain to render smooth and responsive shifts. The electronic clutch pressure control features developed shift control logic for smoother speed and directional shifts, while part-throttle shifting controls transmission shifts for smoother shifting between gears. Controlling loss of momentum during shifts, the shift torque management system carries higher torque via shift points.

For operator comfort, the cab on the 651 is as large as that of a twin-engine 657 and 21 per cent larger than Cat’s E-series scrapers. Ingress and egress have been enhanced with the addition of a powered access ladder. Relocation of the HVAC system, steering column and pedal improve visibility. The new comfort seat rotates up to 30 degrees to the right for loading and provides an additional 2 inches of fore/aft movement to decrease working fatigue. The seat’s adjustable armrest aligns with the execute control level with a T-handle design for more comfortable operation. 

To keep their operators sharper longer, a new high-pressure steering system needs less steering effort and decreases fatigue. Modifications to hydraulics comprise an electrohydraulic implement system for enhanced multifunction capability and a short-throw for the T-handle implement control. 

Cat’s advanced ride management system enhances smoothness by eradicating end-stroke events of the seat suspension cylinder.

An optional three-camera Work Area Vision System (WAVS) displays the cutting edge, right side and rear of the machine on a 7-inch in-cab colour monitor. Available sequence assist decreases up to 14 individual operator commands per cycle with a single button for enhanced cycle consistency, fewer repetitive motions for the operator and less fatigue.