By combining its small-frame CTL platform with the Cat C3.4T DIT engine, high breakout forces and strong auxiliary hydraulic performance, Caterpillar designed the 259B3 as a "power dense" machine capable of taking on the toughest jobs in confined spaces. With premium features such as an independent, fully suspended steel undercarriage, aggressive steel embedded rubber tracks, powerful hydraulics and refined operator's station, the 259B3 completes the CTL line by providing a durable, versatile machine that works productively in poor soils and harsh environments.
At 35 percent tipping load, rated operating capacity for the 259B3 is 2,065 pounds (937 kg), and 2,950 pounds (1 338 kg) at 50 percent tipping load, increasing to 3,000 pounds (1 360 kg) with the optional counterweight. Vertical-lift loader linkage gives the new CTL 120 inches (3 046 mm) of lift height, in combination with excellent reach, for easy truck loading and precise material placement.
Rated at 71 net horsepower (53 KW) the 259B3 is powered by the C3.4T DIT engine, which complies with U.S. EPA Tier-4 Interim and E.U. Stage-3A emissions regulations. This proven engine delivers ample speed and torque in difficult applications, and combined with the Cat anti-stall system, the 259B3 can operate at part-throttle, reducing fuel consumption and lowering sound levels.
Durable, Easy-Riding Undercarriage
The 259B3 is the only machine in its class with a standard, independent, fully suspended undercarriage. Designed and manufactured by Caterpillar, the undercarriage uses four heavy-duty torsion axles (concentric tubular members buffered by an elastomeric material). These extremely durable axles move independently to isolate the machine chassis from the undercarriage and absorb much of the shock from rough-terrain operation. The customer realizes the benefits of suspension in the form of smooth travel, even at high speed, excellent load retention, increased productivity, as well as extended machine and undercarriage component life.
The undercarriage uses triple-flange cast-iron rollers equipped with Caterpillar's exclusive Duo-Cone seals. Large, heavy-duty idlers, front and rear, provide a generous radius that minimizes track bending—yielding longer track life—and contributes to a smooth ride. Front idlers incorporate a recoil system similar to that used on larger Cat Track-Type Tractors.
Two heavy-duty, two-speed hydraulic motors power the 259B3's planetary final drives, which drive single-piece steel sprockets. This powerful drive system combines with aggressive, steel-embedded rubber tracks that provide 59 inches (1 495 mm) of track-on-ground to keep the 259B3 moving productively in tough digging or dozing operations and in poor underfoot conditions. The 259B3 can be equipped with either 12.6 inch (320 mm) tracks or 15.7 inch (400 mm) tracks depending on the customer’s requirements, which yield a ground pressure, respectively, of 6.0 psi (41.2 kPa) and 5.0 psi (34.4 kPa). The standard two-speed travel system is a true ‘no compromise’ design. Planetary reduction drive motors provide excellent torque for pushing, digging and dozing, while providing the speed for high productivity (up to 8.5 mph [13.6 km/h]).
Hydraulic pumps for the 259B3's implement system (boom and bucket) and auxiliary system (for powering work tools) are driven directly from the engine, eliminating intermediate drive belts to assure maximum efficiency, performance and reliability. The robust auxiliary system supplies oil flow up to 22 gpm (83 L/min) at pressures to 3,335 psi (23 000 kPa)—generating a calculated hydraulic-horsepower rating of 42.8 (31.9 kW).
The 259B3 is equipped with Cat ToughGuard XT™ hydraulic hoses, for additional abrasion resistance, and auxiliary lines (with heavy-duty, flat-face quick couplers) are attached to the lift arm. A universal work-tool coupler is standard equipment, and an optional hydraulically actuated coupler is available.
A high-efficiency hydraulic-oil cooler, working with a hydraulically driven cooling fan, keeps the 259B3 working efficiently in high ambient temperatures, even with continuous work-tool operation. The optional variable-speed, on-demand hydraulic fan spins the fan only as fast as required by the machine which improves fuel-efficiency, reduces sound levels and provides faster machine warm-up.
Operator Comfort, Convenience and Safety
Designed for optimal comfort, convenience and safety, the 259B3's spacious operator's compartment features low-effort, pilot-control joysticks—the right controlling lift and tilt functions, and the left, direction and speed. The joysticks provide precise proportional control of auxiliary-hydraulic functions, and optional deluxe joysticks expand the 259B3's capability with control over work-took electrical functions. Both joystick choices provide the convenience of one-touch control of continuous or intermittent auxiliary flow.
The standard open ROPS canopy (with top and rear windows) can be fitted with a cab door, side windows, suspension seat, heater and air conditioning. With both hand and foot throttles as standard equipment, the 259B3 can be set for constant-speed operation (trenching or milling, for instance), or speed can be varied (truck loading and load-and-carry). An anti-stall system is designed to prevent engine stalling, even at part-throttle, by constantly balancing speed and torque demands.
The redesigned dead-engine lower valve further promotes safe operation by providing an easier-to-use, more-positive means of lowering the lift arms—allowing safe exit for the operator—if the machine should run out of fuel or the engine stall with the lift arms raised.
Easy To Service
The 259B3's rear door swings open to allow access to both sides of the engine and all routine maintenance points. An exclusive tilt-up cooling package permits the radiator and oil cooler to be quickly cleaned, and the tilt-up cab provides access to all major hydraulic components and lines. To further assist the service technician, all electrical wiring is color coded, and a Cat S.O.S.TM sampling valve assures regular, accurate monitoring of hydraulic fluid.
- Net Power Rating: hp (kW)
- 71 (53)
- Operating Weight: lb (kg)*
- 8,934 (4 052)
- Rated Operating Capacity: lb (kg)**
- 2,950 (1 338)
- Speed: mph (km/h)
- 5.9/8.5 (9.5/13.6)
- Auxiliary Hyd. Flow: gpm (L/min)
- 22 (83)
- Main Relief Pressure: psi (kPa)
- 3,335 (23 000)
* with 12.6 in (320 mm) tracks
** rated at 50% tipping load