Refined design for Cat D11T and D11T Carrydozer deliver productivity gains

The D11T and D11T CD's 634 kW Cat C32 engine can work fuel efficiently anywhere in the world, and with blades ranging in capacity up to 43.6 m3 and operating weights up to 112 698 kg, the D11T and D11T CD can work productively in the toughest of materials.

Engine technology and cooling

The C32 engine with ACERT technology is configured to meet US EPA Tier-4 Final emissions standards for those geographical areas requiring a high degree of emissions control. For less regulated areas, the engine will be configured to meet US EPA Tier-2 equivalent emissions standards.

The Tier-4 Final configuration employs the Cat NOx Reduction System, which captures and cools a small volume of exhaust gas, then returns it to the combustion chambers to lower temperatures and retard formation of nitrogen oxides. A diesel oxidation catalyst uses oxidation, a chemical process, to condition exhaust gases to meet emission standards.

A new cooling package uses a two-part radiator with aluminum bar-plate cores that contribute to durability, efficient heat transfer and corrosion resistance. The new oil-to-air hydraulic-oil cooler uses similar construction, and a hydraulically variable demand fan uses less power, reduces fuel consumption and lowers sound levels.

Performing at full rated net power of 634kW at 1800rpm with a high torque rise of 21 percent, the large displacement and high torque allow the D11T to doze through tough material. It is matched to a highly efficient power shift divider and electronically controlled power shift transmission, providing years of dependable service. There are three speeds forward and three speeds reverse, utilising large diameter, high capacity, oil cooled clutches.

Drive train and undercarriage

New for the D11T and D11T CD is the Enhanced Auto Shift (EAS) system, designed to conserve fuel by automatically selecting the optimal reverse gear and engine speed, based on load and desired ground speed. When the EAS mode is not activated, an Auto Downshift feature automatically change gears down to most efficiently handle loads.

A single stage torque converter with output divider sends 75 percent of engine torque through the converter and 25 percent through a direct drive shaft for greater driveline efficiency. The torque converter shields the driveline from sudden torque shocks and vibrations.

Operator environment and safety

The D11T and D11T CD's spacious, well-appointed cab features single-joystick blade control, fingertip steering, automatic climate control and Cat Comfort Series seats that are now available with a heated and ventilated option.

A new Dynamic Inclination Monitor provides a read out of tractor pitch angle and side-to-side slope angle, and Automated Blade Assist Control uses preset blade-pitch positions to simplify positioning. An optional Autocarry system automatically controls the blade during the carry segment.

A new operator presence system locks out the power train and hydraulic system to avoid unintentional machine movement when the operator is entering or leaving the cab, which can be done via an optional hydraulically actuated access ladder that deploys and stores in seconds.

An optional sound-suppression package reduces average spectator sound power levels for both the operator and the surrounding environment benefit.

Ease of operation is a key to the D11T with the dozer control joystick providing the operator control of all dozer functions with one hand. Fore/aft movement of the joystick lowers and raises the blade. Left/right movement directionally tilts the blade. Blade response and blade float can be set/adjusted using the Advisor Panel. The thumb lever at the top of the handle and trigger switch controls blade pitch fore and aft. A semi-automatic dozer control allows the setting of presets for blade pitch positions for load, carry and spread elements. This increases efficiency while reducing operator workload.

Serviceability

The D11T and D11T CD features an "OK-to-Start" system that electronically checks critical fluid levels. Routine maintenance is facilitated by easily accessed filters, an optional automatic lubrication system, high speed oil change for engine and powertrain systems, and ecology drains for capturing fluids for proper disposal or recycling. A fast-fill fueling system incorporates a positive shut off to prevent spills.