Engine

The Cat C7.1 ACERT™ engine is designed to deliver more power than ever before, while still achieving the highest levels of total fluid efficiency, reliability and durability.

The C7.1 ACERT engine meets U.S. EPA Tier 4 Final and EU Stage IV emission standards using a blend of technologies to optimize performance, whatever the conditions. The Selective Catalytic Reduction (SCR), Exhaust Gas Recirculation (EGR) and Diesel Oxidation Catalyst (DOC) systems effectively remove NOx gasses from the exhaust, while a fully passive, service-free Diesel Particulate Filter (DPF) removes soot and other particulates. All Cat C7.1 ACERT emissions technologies are designed to be transparent, so you are free to concentrate on the job at hand.

The High Pressure Common Rail Fuel System provides precise and efficient combustion, allowing for maximum performance improved fuel efficiency and enhanced reliability. Series turbochargers provide extra power when needed. The engine is designed for maximum uptime and reduced operating costs, with world-class support from the Cat dealer network.

Industry leading integration and engineering support is at the heart of everything we do. The Cat C7.1 ACERT engine is fine-tuned to work seamlessly with machine control systems, optimizing the engine for demanding work cycles.

With a durable design and long life, the C7.1 ACERT delivers better fuel economy, with minimized maintenance costs, while still providing the same great power and response you expect.

Cooling System

The high capacity cooling system and on-demand hydraulically driven reversing fan keep the machine running at the proper operating temperature, optimizing performance, durability and fuel efficiency. The system, designed to meet the cooling requirements of the 555D, is common to all models, boosting fuel efficiency and capacity in the smaller models.

Power Train

Power to the ground is an advantage of the Cat D Series. The axles are designed specifically for the skidder application and the gear ratios cause the power to be generated in the axles reducing torque in the transmission and drivelines extending their life. Both drawbar performance and durability are improved.

Hydraulics

The new hydraulic system gives the D Series more speed, increased multifunctioning capability and greater lift capacity. This efficient load sense system with variable displacement pump continually monitors hydraulic power requirements and provides power based on demand to save fuel.

Structures

Robust frames provide a solid foundation for a machine designed to provide long life. Every structure was engineered for durability and verified through lab and field tests.

Arches and Boom

Box-section construction was used in the arch and boom designs to transfer heavy loads efficiently into the main frames. The arch gate is integrated into the arch and comes with a bolt-on fairlead roller assembly for skidders ordered with a winch, or a bolt-on guard, for skidders not equipped with a winch.

The dual function arch and boom is available on all models while the single function arch is available on the 525D and 535D. The cable arch is available on all except the 555D.

Grapple

The 360° continuous rotation grapple features box-section construction and threaded grapple tong pins that maximize structural integrity. Additional internal support and around the grapple tong pin increases rigidity while service panels provide access to all grapple head components.

The grapple tongs are shaped to roll trees up quickly for a fully loaded grapple. Tight clamping forces and raised edges on the tongs keep the drag secure during transport while providing extended wear life. Tongs have replaceable wear tips and are reinforced internally to support twisting loads. Internal welding in high wear areas increases the durability and extends the life of the tongs.

Winches

Logging and retrieval winches are available as options. Both are hydraulically driven, have the same pulling power and feature friction style clutches for increased durability and functionality. Both the retrieval and logging winches are operated by a joystick for more control over the reeling speed.

Operator Station

The new D Series cab is roomy, quiet and cool with great visibility, especially out the back.

Serviceability

Serviceability of the D Series is significantly improved with the tilting cab, redesigned grapple head and improved hose routings. Keeping the machine clean is easy, too.

Customer Support

Caterpillar is known the world over for the quality of customer support from its dealer network – the industry’s best. No matter where you are, the expertise of a Cat dealer is always nearby. Your local Cat dealer is your forestry consultant who can recommend the machines, work tools and services to maximize your operation and provide the support to keep you at top productivity.

• 24-hour parts availability, where and when you need them, to minimize expensive downtime.
• Remanufactured parts that carry the same warranty as new parts at a reduced cost.
• Operator training to get the most out of your Cat equipment.
• Field services to provide on-site help when needed.
• Timely repair and replacement services.
• Customer Support Agreements to lower your operating costs.
• State-of-the-art diagnostic programs, such as S·O·SSM oil analysis, inspection services and trend reporting to help avoid unscheduled repairs.
• Financing programs for buying, renting or leasing Cat equipment.
• Cat Financial Commercial Account, a fast and convenient way to pay for or rent anything offered at any Cat dealer or The Cat Rental Store.
• Cat Insurance to cover equipment losses from theft, collision, flood, upset or overturn, fire, vandalism and more.
• Product Link™ to manage your equipment fleet through remote monitoring.
• Cat Certified Rebuild to get a second life from your equipment.

Sustainability

The D Series wheel skidders are designed to maximize efficiency and productivity while conserving natural resources.

• The C7.1 ACERT engine meets U.S. EPA Tier 4 Final and EU Stage IV emission standards.
• The D Series is more fuel efficient which means reduced emissions per unit of work performed.
• Fewer parts and longer component life, less fuel and fluids, means less to replace and less to dispose.
• Major structures and components are built to be rebuilt, reducing waste and replacement costs.

Integrated Technologies

Caterpillar offers solutions to help you work smarter.

Safety

Safety is critical in the woods and a number of unique safety features have been designed into the D Series skidders, including:

• Ground level fueling
• Ground level daily maintenance
• ROPS/FOPS/OPS certified cab with tough Lexan windows
• Weight distribution and longer wheel base that maximize stability
• Additional mesh screen guarding on side windows
• Pressurized operator station for a clean, quiet environment
• 360° visibility of the work area from the cab
• Safe and secure access into and out of the cab with grab handles and steps with gripper surface
• Forestry-duty cooling packages
• Debris management includes reversing fan to keep debris from clogging airflow inlets, segregated cooling package that allows debris to pass through and not collect or migrate to the engine compartment
• Ground level machine kill switch
• Halogen working lights