Caterpillar designs its track-type tractors to meet worldwide customer demand with regard to performance, operator comfort, ease of operation, safety, and versitility. The D6N Forestry Guarding Arrangement gives you a rugged machine that meets the most demanding applications.

Engine Model Cat® 3126B
Flywheel Power 145 hp
Bore 4.33 in
Stroke 5 in
Displacement 439 in3

Operating Weight 38113 lb
Operating Weight XL-DS 38113 lb
Shipping Weight XL-DS 37381 lb
Operating Weight LGP-DS 42344 lb
Shipping Weight LGP-DS 41611 lb

Blade Type SU, VPAT
XL SU - Blade Capacity 5.6 yd3
XL SU - Blade Width 10.5 ft
XL, VPAT - Blade Capacity 4.16 yd3
XL VPAT - Blade Width 10.73 ft
LGP, VPAT - Blade Capacity 4.13 yd3
LGP VPAT - Blade Width 13.4 ft

1.0 Forward 2.1 mph
2.0 Forward 3.6 mph
3.0 Forward 6.3 mph
1.0 Reverse 2.5 mph
2.0 Reverse 4.3 mph
3.0 Reverse 7.4 mph
Drawbar Pull - 1.0 Forward 71000 lb
Drawbar Pull - 2.0 Forward 38800 lb
Drawbar Pull - 3.0 Forward 21500 lb

Width of Shoe - XL 24 in
Width of Shoe - LGP 34 in
Shoes/Side - XL 40
Shoes/Side - LGP 46
Grouser Height 2.24 in
Track Gauge - XL 74 in
Track Gauge - LGP 85 in
Track on Ground - XL 100 in
Track on Ground - LGP 122 in
Ground Contact Area - XL 4822 in2
Ground Contact Area - LGP 8269 in2
Track Rollers/Side - XL 7
Track Rollers/Side - LGP 8

Service Refill Capacities
Fuel Tank 79 gal
Cooling System 10.75 gal
Final Drives (each) 1.8 gal
Hydraulic Tank 7.8 gal

Winch Model PA55
Weight* 2513 lb
Oil Capacity 19.55 gal
Winch and Bracket Length 44.1 in
Winch Case - Width 38.4 in
Drum Diameter 10 in
Drum Width 12.4 in
Flange Diameter 19.8 in

Ground Clearance 16.7 in
Width without Blade 98 in
Width with Blade 116.5 ft
Height ROPS/Canopy 10.28 ft
Overall Length Basic Tractor (with Drawbar) 12.27 ft
Overall Length with Blade 18.1 ft

Weight - With One Shank 3100 lb
Type Fixed Parallelogram
Number of Pockets 3
Overall Beam Width 86.7 in
Beam Cross Section 216 x 254 mm 8.5 x 10.0 in
Maximum Penetration - XL 18.6 in
Maximum Penetration - LGP 14.2 in
Weight - Each Additional Shank 172 lb

Forestry/Land Clearing Guarding
Extensive Guarding helps protect critical machine components, body panels and the cooling system from being damaged by debris in clearing and forestry-related environments.

Heavy-Duty Hinged Radiator Grille
This grille is an angled plate type grille, hinged for easier access. A lockable, hand-operated latch is included. The 45° angle of the bars diverts airflow up and away from the back of the dozer blade. The angle also helps keep debris from damaging the radiator.

Heavy-Duty Bottom Guards
These guards prevent debris from damaging powertrain components and help keep debris out. The Heavy-Duty Guards include heavier construction for stronger protection.

Lift Cylinder Lines Guards
Help protect the hydraulic tubes on the lift cylinders from damage.

Heavy-Duty Engine Enclosures
Perforations sized to enhance airflow while limiting debris entry. Front hinged for easy access. Note: If Sound Suppression arrangement is ordered, the perforated doors are replaced with solid doors.

Perforated Hood
Perforations sized to enhance airflow while limiting debris entry.

Heavy-Duty Hydraulic Tank Guard
Includes a hinged cover to protect the filter housing and fill spout.

Heavy-Duty Fenders
  • Twice as thick as standard.
  • Includes edge protection for sheet metal panels.
  • Maintains serviceability.

Polycarbonate Front Windshield
  • Meets OSHA forestry guarding requirements.
  • Scratch resistant.

Heavy-Duty Battery Box and Sheet Metal
Thicker steel for more structural strength.

Heavy-Duty Latches
On sheet metal access panels and engine enclosures.

Wider Sweeps
  • Keeps branches further away from cab for better protection.
  • Front sweep arms align with cab to further improve visibility.

Heavy-Duty Fuel Tank Guard
  • 10mm (.375 in) thick steel for maximum strength.
  • Includes fuel fill cap protection.
  • Adds additional stiffness to structures.

Hinged Rear Screen
  • Protects glass from damage by trees.
  • Can be opened from inside or outside for easy cleaning access.
  • Protects air conditioner condenser unit.

Heavy-Duty Side Screens
  • Meet OSHA standards for forestry-related work.
  • Hinged to allow easier cleaning access.

Debris Resistant Features
A debris resistant cooling system helps reduce plugging, extend service life, and enhance productivity.

Debris Guards
Several guards are added to prevent damage to sheet metal panels from debris carried by the track.

Recommended Options
Several additional options are recommended to complement the Forestry Guarding Arrangement and ensure peak performance. Consult with your Caterpillar dealer for further recommendations.

Heavy-Duty Rear Guard
  • 10mm (.375 in) thick steel for maximum protection.
  • Lockable for vandalism protection.

Tilt Lines Guards
Additional guards added for bulldozer tilt lines.

Trash Resistant Cooling System
  • Wider 6 fins/inch spacing.
  • Allows longer run time between cleanouts.
  • Easier to keep clean.

Differential Steering System
Differential Steering maintains power to both tracks while turning. Operator controls machine speed, direction and steering with the tiller bar controller, while maximizing production.

Tiller Bar Control System
The tiller bar control system allows for simultaneous comfortable, one-handed steering, direction and transmission control.
  • The differential steering tiller bar has easy touch shift buttons for upshifts and downshifts.
  • The tiller bar is easily pushed forward to steer the tractor to the left and pulled backwards to steer the tractor to the right.
  • The farther the tiller bar is moved, the tighter the turn.
  • To change machine direction, operators rotate the tiller bar clockwise for forward or counterclockwise for reverse. Neutral transmission position is in the middle between the two.
  • Low tiller bar efforts assure operator comfort during long shifts.

Power Turn with Differential Steering
With differential steering, large blade loads can be smoothly maneuvered throughout the turn. The operator maintains precise control on slopes, around buildings, bridge abutments, trees or other obstacles.
  • Differential Steering has the ability to work in tight areas by providing a “Best in Class” tight turning radius.
  • Steering modulation is finely tuned for precise control in all turning applications.
  • Regardless of ground conditions, steering is consistent because power is maintained to both tracks during operation.

Differential Steering System
A planetary differential turns the machine by speeding up one track and slowing the other while maintaining full power to both. The differential steering system consists of:
  • Three planetary gear sets.
  • A dedicated variable-displacement hydraulic pump.
  • A bi-directional, fixed-displacement steering motor.
  • Heavy-duty steering drive gears.
  • Two planetary gear sets (steering and drive) make up the dual differential.
  • A third planetary gear set, the equalizing planetary, resides in the main case and provides a maximum 4.0 km/h (2.49 mph) speed difference between tracks.

When moving straight ahead, power flows through the transmission pinion and bevel gear into the dual differential, transmitting equal, uninterrupted power to each final drive. While turning, power is shifted to the outboard track speeding it up. The inboard track slows down to accommodate a tighter turning radius. Forward ground speed remains the same throughout the turn.

1 Operator's Station
State-of-the-art operator’s station has reduced sound levels, lower cab vibration, and increased glass area.

2 Steering Control
Differential Steering Tiller Bar control system and the optional Finger Tip Control (FTC) steering system provide simultaneous one handed steering and transmission control.

3 Differential Steering Motor
Bi-directional hydraulic steering motor activates the dual differential, which changes the speed of individual tracks. Slowing one track and increasing the speed of the other track achieves a smooth power turn.

4 Power shift Transmission
Proven planetary design provides fast smooth speed changes while distributing loads over multiple gears for long life.

5 Final Drive
Caterpillar elevated final drives provide isolation from ground or work tool impact loads, extending service life.

6 Brake Assembly
Oil cooled large diameter brake disc provide long service life.

7 Engine
Caterpillar 3126B HEUI engine meets EPA Tier 2 and EU Stage II exhaust emission regulations.

8 Radiator
Multiple Row Modular (IMRM) radiator is less subject to plugging and provides excellent heat transfer.

9 Torque Converter
Efficient torque converter provides torque multiplication for increased drawbar pull and protects the drive train from shock loads.

The Caterpillar elevated sprocket undercarriage arrangements are designed for optimized balance and best possible performance in fine grading to heavy dozing applications.

Elevated Final Drive
  • Isolates final drives from ground and work tool induced impact loads for extended power train life.
  • Keeps sprocket teeth, bushings and final drives away from abrasive materials and moisture.
  • Caterpillar uses single reduction planetary final drives in the D6N providing long-lasting performance and durability.

Undercarriage Arrangements
XL (Extra Long) arrangement
  • Forward idler position provides more track on the ground and to the front of the tractor. It provides optimal balance, superior traction and blade control for finish grading.
  • Long roller frame provides good flotation in soft underfoot conditions. LGP (Low Ground Pressure) arrangement
  • Specially designed to work in soft and spongy conditions.
  • Wide track shoes, long track frames and a wider gauge increase track contact area and reduce ground pressure for excellent flotation.

Rotating Bushing Track
Rotating Bushing Track is designed to extend system life and lower costs in highly abrasive low to moderate impact applications. RBT features bushings which rotate when in contact with the sprocket, greatly reducing bushing and sprocket wear. This design eliminates bushing turn maintenance expense and sprocket replacement costs. Rotating Bushing Track is available as optional undercarriage.

Complete Guarding
Caterpillar undercarriages are designed with full length guarding on top of the track roller frame. This prevents abrasive materials from falling down on moving parts.

Roller Frames
Roller frames are tubular, to resist bending and twisting.
  • Roller frames attach to the tractor by a pivot shaft and pinned equalizer bar.
  • The recoil system is sealed and lubricated.

Recoil SystemOscillating Undercarriage
Power train
3126B HEUI meets EPA Tier 2 and EU Stage II emission regulations and offers increased performance levels.

Cat 3126B HEUI Engine
Caterpillar electronic engines meet worldwide emission requirements for the EPA Tier 2 and the EU Stage II regulations. With the HEUI™ fuel system, injection pressure is independent of engine speed and provides maximum fuel delivery efficiency with low exhaust emissions. The Cat 3126B engines are equipped with an electronic air inlet heater. This warms the air in the air inlet manifold for easier starting and reduces white smoke on cold starts. Machines will automatically activate the timed air inlet heater prior to engine startup.

Turbocharged and Aftercooled
A well-matched turbocharger and air-to-air aftercooler results in higher power while keeping rpm steady and exhaust temperatures low.

Torque Rise
The direct injected electronic fuel system provides a controlled fuel delivery increase as the engine lugs back from rated speed. This results in increased horsepower above rated power. A combination of increased torque rise and maximum horsepower improves response, provides greater drawbar pull and faster dozing cycles. The 127 kW (170 hp) maximum flywheel power occurs at 1600 rpm when power is needed during severe applications.
  • Rated flywheel power 108 kW (145 hp).
  • Maximum flywheel power 127 kW (170 hp).

3126B Engine Features
The 3126B major features include:
  • Increased power to 108 kW (145 hp) on both the Differential Steering and FTC configurations for increased performance.
  • 70 percent net torque rise on the D6N machines.
  • Large displacement electronic engine with lower exhaust emissions and improved cold start capability.
  • Power train to engine link with electronic controlled throttle shifting.
  • New Poly-Vee serpentine engine fan belt with auto tension feature eliminates the traditional three to four belt system.
  • Extended oil and engine filter change intervals up to 500 hours after break-in.
  • ATAAC cooling system.
  • Multiple Row Modular (IMRM) radiator is less subject to plugging due to a unique radiator fin design which provides excellent heat transfer capability.

Drive Train
Rugged, durable and reliable components deliver smooth, responsive power and lasting reliability.

Torque Converter
The D6N single stage torque converter efficiently responds to changing load conditions by providing torque multiplication, therefore increasing drawbar power. It also provides protection to the drivetrain components by preventing shock loads from heavy dozing applications. This torque converter is efficiently matched to the powertrain components and provides superior performance you need.

Auto-shift allows the operator to pre-select a forward and reverse gear for easy, efficient directional changes. Auto-shift settings include:
  • First forward to second reverse.
  • Second forward to second reverse.
  • Second forward to first reverse.
Auto-kickdown allows the transmission to automatically downshift when significant load increases are detected.

The proven planetary powershift transmission features three speeds forward and three speeds reverse and utilizes large diameter, high capacity, oil cooled clutches. To maximize the life of the transmission, the planetary design distributes loads and stresses over multiple gears.
  • Controlled throttle shifting regulates engine speed during high-energy directional shifts for smoother operation and longer component life.
  • The transmission and bevel gear set are modular by design, and easily slide into the machine's rear case, even with the ripper installed.
  • Forced oil flow lubricates and cools clutch packs to provide maximum clutch life.
  • Load compensating shifting provides smooth engagement of the clutches under loaded conditions.

Steering Clutch and Brakes
Oil cooled, hydraulically actuated, large diameter plates and clutch discs provide higher torque capacity and increased service life.

Elevated Final Drive
Final drives are isolated from ground and work tool induced impact loads for extended powertrain life.

Steering and Transmission Controls
The D6N offers both Differential Steering and Finger Tip Controls for steering. Both systems deliver the control the operators need for all applications. Soft touch buttons located on the steering controls shift the electronically controlled transmission.

Electronic Clutch Pressure Control
The D6N has an additional transmission shifting feature for added performance and operator comfort - the Electronic Clutch Pressure Control (ECPC). This unique feature provides smoother shifting by regulating and modulating the individual clutches based on current operating conditions.

Operator Station
State-of-the-art operator station has reduced sound levels, lower cab vibrations and excellent visibility. The (optional) Caterpillar comfort series air suspension seat helps reduce operator fatigue. Cab and air conditioning are standard.

Operator Station

The new cab incorporates large glass window and door panels. This allows for increased visibility to the blade, rear and sides of the machine. New door and window seal design allows for a fully pressurized low dust cab. Low acoustic headliner material and sound suppression foam panels reduce sound levels to 79 dB(A) according to the dynamic test procedure and conditions that are specified in ISO 6394:1998. The cooling system is incorporated into the cab structure providing good visibility to the rear of the machine. Individual windshield wiper controls are located in the front section of the headliner. The new design is spacious and comfortable to promote shift-long productivity.

Cat C500 Comfort Suspension Seat
Caterpillar C500 Comfort Series Air Suspended Seat is ergonomically designed to support the operator in various site conditions (optional).
  • Seat is fully adjustable for maximum operator comfort, support and reduced operator fatigue.
  • Seat cushion reduces pressure on the lower back and thighs while allowing unrestricted arm and leg movement.
  • A standard lumbar adjustment provides lower back comfort.

The new instrument panel, with easy to read analog gauges and warning lamps, keeps the operator aware of any potential problems. All gauges and readouts are easily visible in direct sunlight. HVAC controls and vents are conveniently located on the dash to provide climate control for the operator. Auto-shift and Auto-kickdown controls are located within easy reach of the operator. New footpads keep the operator stable and comfortable while working on slopes.

Electronic Monitoring System (EMS-III)
EMS III provides the operator instant feedback on machine conditions and records performance data to help diagnose problems. It has flashable memory allowing system upgrades, as new technology and software become available. This system is compatible with Cat ET and CMS service tools. EMS includes the following gauges and readouts:
  • Fuel level gauge
  • Hydraulic oil temperature gauge
  • Engine coolant temperature gauge
  • Power train oil temperature gauge
  • Engine oil pressure indicator
  • Engine speed digital readout
  • Transmission gear indicator
  • Hour meter
  • Odometer

Finger Tip Control (FTC)
Located to the operator’s left, finger tip controls provide one-handed operation. They control steering, machine direction and gear selection.
  • Finger tip levers allow operators to work with precision in close areas.
  • Push buttons control three speed forward/reverse gear selection.

Ergonomic Work Tool Controls
Ergonomically shaped blade and ripper controls have low lever efforts for reduced operator fatigue. The voltage converter provides a 12-volt power supplies.

The major component modular design concept moves a generation ahead in simplified service and repair. Customer support is unmatched in the industry.

DiagnosticsGrouped Service Points and AccessibilityProduct Link
This option allows the customer or dealer to obtain machine diagnostics and location from their offices. Product Link provides updates on service meter hours, machine condition, machine location as well as integrated mapping/route planning.

Electronic Monitoring System
The D6N features a more flexible monitoring system that is easily upgraded by flashing software rather than replacing the module, reducing parts cost. As technology changes and new electronics and software become available, this upgraded monitoring system will allow the machine to be easily updated.

Built-in Serviceability
Less service time means more working time. Major components are designed as modules and most can be removed without disturbing or removing other components.

Diagnostic Connector
Diagnostic connector allows Caterpillar dealers to quickly troubleshoot the D6N or access stored data with the use of Electronic Technician (Cat ET).

Ecology Drains
Ecology drains provide an environmentally safer method to drain fluids. They are included on the radiator, hydraulic tank and major power train components.

Modular Cooling System
Individual radiator core modules are easily serviced without major component removal.

Easy Engine Maintenance
Many parts can be rebuilt and are available as remanufactured components.
  • Parent-metal block can be rebored twice and dry-sleeved.
  • Connecting rods can be removed through cylinder tops.
  • Camshaft followers and push rods can be replaced without removing camshaft.
  • Extended oil and engine filter change intervals up to 500 hours.

Total Customer Support
Your Cat Dealer offers a wide range of services that can be set up with a Customer Support Agreement. The dealer can customize a plan for you, from PM service to total machine maintenance, allowing you to optimize your return on investment.

Total Customer Support

Product Support
Your Cat Dealer offers a wide range of services that can be set up under a Customer Support Agreement (CSA) when you purchase your equipment. The dealer will help you choose a plan that can cover everything from the machine and attachment selection to replacement. This will help you get the best return on your investment.

Remanufactured Components
Save money with remanufactured parts. You receive the same warranty and reliability as new products at a cost savings of 40 to 70 percent.

Service Capability
Whether in the dealer’s fully equipped shop or in the field, you will get trained service technicians using the latest technology and tools.

Make detailed comparisons of the machines you are considering before you buy. How long do components last? What is the cost of preventive maintenance? What is the true cost of lost production? Your Cat Dealer can give you answers to these questions.

Consider the financing options available as well as day-to-day operating costs. This is also the time to look at dealer services that can be included in the cost of the machine to yield lower equipment owning and operating costs over the long run.

Improving operating techniques can boost your profits. Your Cat Dealer has training videotapes, literature and other ideas to help you increase productivity.

Repair, rebuild or replace? Your Cat Dealer can help evaluate the cost involved so you can make the right choice.

More and more equipment buyers are planning for effective maintenance before buying equipment. Choose from your dealer’s wide range of maintenance services at the time of your purchase. Repair option programs guarantee the cost of repairs up front. Diagnostic programs such as Scheduled Oil Sampling and Technical Analysis help avoid unscheduled repairs.



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