3126B HEUI™ meets EPA Tier 2 and EU Stage II emission regulations and offers increased performance levels.
Cat 3126B HEUI EngineCaterpillar 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 AftercooledA well-matched turbocharger and air-to-air aftercooler results in higher power while keeping rpm steady and exhaust temperatures low.
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.
Rugged, durable and reliable components deliver smooth, responsive power and lasting reliability.
Torque ConverterThe 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 drive train components by preventing shock loads from heavy dozing applications. This torque converter is efficiently matched to the power train 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 BrakesOil cooled, hydraulically actuated, large diameter plates and clutch discs provide higher torque capacity and increased service life.
Elevated Final DriveFinal drives are isolated from ground and work tool induced impact loads for extended power train life.
Steering and Transmission ControlsThe 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 ControlThe 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.
Power Turn Differential Steering
A D6N equipped with Differential Steering maintains power to both tracks while turning. Operators have control of 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.
OperationWhen 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 StationState-of-the-art operator’s station has reduced sound levels, lower cab vibration, and increased glass area.
2 Steering ControlDifferential 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 MotorBi-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 TransmissionProven planetary design provides fast smooth speed changes while distributing loads over multiple gears for long life.
5 Final DriveCaterpillar elevated final drives provide isolation from ground or work tool impact loads, extending service life.
6 Brake AssemblyOil cooled large diameter brake disc provide long service life.
7 EngineCaterpillar 3126B HEUI engine meets EPA Tier 2 and EU Stage II exhaust emission regulations.
8 RadiatorMultiple Row Modular (IMRM) radiator is less subject to plugging and provides excellent heat transfer.
9 Torque ConverterEfficient torque converter provides torque multiplication for increased drawbar pull and protects the drive train from shock loads.
State-of-the-art operator’s 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 now offered as standard.
CabThe 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.
DashThe 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
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 ControlsErgonomically shaped blade and ripper controls have low lever efforts for reduced operator fatigue. The voltage converter provides a 12-volt power supplies.
Modern styling with rounded shapes and tapered hood enhances operator visibility. The N-Series combines eye-catching styling with solid, reliable performance.
New styling with rounded machine shapes offers excellent visibility, accessibility and serviceability.
- Durable, heavy steel door panel covers.
- Pre-cleaner is below the hood for increased visibility.
- Engine enclosure is tapered as it reaches the cab.
- Large amounts of glass area in cab.
- Controls are ergonomic for easier operation and better efficiency.
Accessibility and Serviceability
- Hinged engine doors to increase engine and service access.
- Remote-mounted filters located within easy reach during PM service.
- Air pre-cleaner filter condition monitor located in the cab for high visibility.
- Redesigned fuel tank for easier internal cleaning.
- Fast fuel tank provision added (attachment).
- Larger service panel doors.
- Diagnostic test ports added for quick troubleshooting.
Quality and Reliability
- Doubled 4 mm (0.16 in) sheet metal on the side service access panels and rear guard.
- Stamped, rounded sheet metal corners add strength.
- Rubber isolation mounted fuel tank eliminates tank vibration and reduces potential stress fractures.
- Heavy duty reinforced radiator guard is now standard.
- Heavy duty rear guard for ripper.
- Clipped seals provide protection from dust and moisture for:
- rear enclosure - door openings - between ROPS post and rear enclosure
Engineered and built to give solid support in the most demanding applications. Designed to last throughout the extended service life of the D6N.
Frame and Castings
The D6N case and frames are built to absorb high impact shock loads and torsional forces. Castings are strategically located within the frame to add additional strength. Caterpillar uses robotic welding techniques in the assembly of the case and frames. This insures quality and reliability throughout the structure.
- High strength steel mainframe resists impact shock loads.
- Computer-aided finite element analysis is used to evaluate and ensure durability.
- Full scale structural testing to test integrity of the structures.
- Robotic welding provides deep penetration and consistency for long life.
- Precision top level machining for perfect alignment of bores and surfaces.
- Pivot shaft and pinned equalizer bar to maintain track roller frame alignment.
Equalizer BarThe pinned equalizer bar gives the roller frames the ability to oscillate up or down to better match ground contours while providing maximum traction and operator comfort.
Roll Over ProtectionN-Series cab supports have been stiffened. Stiffer cab supports result in lower noise and vibration in the cab, providing the operator increased comfort.
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.
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 TrackRotating 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 GuardingCaterpillar 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 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.
Modular design moves Caterpillar a generation ahead in simplifying service and maintenance.
Grouped Service Points and Accessibility
Product LinkThis 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 SystemThe 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 ServiceabilityLess service time means more working time. Major components are designed as modules and most can be removed without disturbing or removing other components.
Diagnostic ConnectorDiagnostic connector allows Caterpillar dealers to quickly troubleshoot the D6N or access stored data with the use of Electronic Technician (Cat ET).
Ecology DrainsEcology drains provide an environmentally safer method to drain fluids. They are included on the radiator, hydraulic tank and major power train components.
Modular Cooling SystemIndividual 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.
Cat D6N work tools are designed to provide strength and flexibility to match the machine to the job.
With superior moldboard and 4-cell structure design, Cat bulldozer blades hold up to the toughest job conditions. Our high-tensile strength blades resist torsional bending and deflection in tough applications.
- High-tensile strength, Cat DH-2™ steel, cutting edges resist bending.
- DH-3™ steel end bits maximize service life.
Variable Pitch Power Angle and Tilt Blade (VPAT)
The VPAT blade gives the operator the ability to hydraulically adjust the blade lift, angle and tilt from the operator’s station.
- Manually adjustable blade pitch for optimum performance.
- Top corners of the blade are clipped for better operator viewing area. (XL arrangement only).
- C-Frame is solidly pinned to the main frame for good blade control and eliminates blade motion due to track oscillation or side forces.
- C-Frame to tractor joint is sealed and lubricated with remote lines for extended service life and quiet operation.
- Large C-Frame tower bearings have been added to improve durability.
- Lubrication points are located at all pin joints to reduce wear.
Semi-Universal Blade (XL Arrangement Only)Built for tough applications where penetration and blade side loading are important. The design of the SU blade makes it excellent for aggressive dirt penetration and loading materials. The blade wings are designed for superior load retention.
Foldable Blade (D6N LGP Arrangement Only)Designed to conform with the 3 m (9.8 ft) width transport limit without blade removal. Allows a 0.30 m (1 ft) section on both ends of the blade to fold into transport position.
The multi-shank parallelogram ripper lets you choose one, two or three shanks depending on job conditions.
- Curved or straight ripper shanks are available.
- Excellent chassis durability in severe drawbar applications.
The D6N can be equipped with a drawbar for pulling work tools such as:
- Chopper wheels
- Retrieval of other equipment
- Single lever control actuates both clutch and brake functions to improve operator efficiency.
- Input clutches on PTO shaft reduce engine horsepower loss for fuel efficiency.
- Clutch engagement and brake release are automatically synchronized for smooth operation.
- Winch components can be serviced with winch mounted on tractor.
Check with your Caterpillar Dealer for details.
Forestry SweepsIn forestry and land clearing applications where limbs and debris can damage a machine, optional sweeps are available for the N-Series. Sweeps help to shield critical components on the tractor such as hydraulic lines, exhaust stacks, cab windows and lights from damage.
Rear CounterweightRear counterweights are available through Custom Products and can be used to help the machine's balance in severe applications such as backing up slopes or heavy angle dozing.
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.
Product SupportYour 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 ComponentsSave money with remanufactured parts. You receive the same warranty and reliability as new products at a cost savings of 40 to 70 percent.
Service CapabilityWhether in the dealer’s fully equipped shop or in the field, you will get trained service technicians using the latest technology and tools.
SelectionMake 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.
PurchaseConsider 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.
OperationImproving operating techniques can boost your profits. Your Cat Dealer has training videotapes, literature and other ideas to help you increase productivity.
ReplacementRepair, rebuild or replace? Your Cat Dealer can help evaluate the cost involved so you can make the right choice.
MaintenanceMore 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.