Earthmoving Report: Clean-Running Cat D11T Easy on Operators

By Walt Moore, Editor | November 8, 2011

With operating weights that can approach nearly a quarter-million pounds, and with blades that can handle up to 57 cubic yards, the 850-horsepower Cat D11 crawler dozer, in production since 1986, probably is as close to being an irresistible force as anything on tracks. But for all of its brute strength, says Caterpillar, the D11 exhibits refined performance and provides a high degree of operator convenience, comfort and safety—all of which have been notched up with recent engineering enhancements in the D11T and its “Carrydozer” counterpart, the D11T CD.

The Cat C32 ACERT engine used in the new D11T and D11T CD is available in two configurations, one meeting U.S. EPA Tier-4-F standards for areas requiring a high degree

of emissions control, and the other meeting 2006 U.S. EPA Tier-2-equivalent emissions levels for lesser regulated areas.

A new cooling package uses a two-part radiator with aluminum bar-plate cores, new hydraulic-oil cooler with similar construction, and a new hydraulically variable demand fan designed to reduce fuel consumption and lower sound levels.

Operator amenities and serviceability

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. Also new is the Dynamic Inclination Monitor, providing a readout of tractor pitch angle and side-to-side slope angle.

 New visibility packages provide a wider view of the work area with interior and exterior mirrors and with the Work Area Vision System (WAVS), a closed-circuit camera system. An available Object Detection system uses radar technology to further increase operator awareness, and 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.

An optional sound-suppression package—using solid engine enclosures and bottom guards with liners and seals—reduces average spectator sound power levels by 6 dB(A) and cab-interior levels by 4 dB(A). A new automatic climate-control system is standard, and Cat Comfort Series seats are now available with heat and ventilation. An optional Automated Ripper Control system adjusts ripper depth and engine speed to minimize track slip and to reduce operator fatigue.

A new “OK-to-Start” system electronically checks critical fluid levels, and routine maintenance is facilitated, says Caterpillar, with an optional automatic lubrication system and ecology drains. For efficient machine management, the D11T’s Product Link system, says the company, allows remote monitoring of the machine and provides critical data, including diagnostic codes, operating hours, fuel consumption and idle time.