Komatsu D31EX-21, D31PX-21, D37EX-21, D37PX-21, D39EX-21, D39PX-21 Bulldozer Shop Manual • P/N SEBM035005, November 2007
Komatsu Models Covered & Key Technical Specifications
Models: Komatsu D31EX-21, D31PX-21, D37EX-21, D37PX-21, D39EX-21, D39PX-21
Sub-models / Variants: EX-21, PX-21, 400 mm Single shoe, 600 mm Single shoe, 600 mm Swamp shoe, 460 mm Single shoe, 635 mm Single shoe, 700 mm Swamp shoe
Model Years: 2007
Serial Numbers: D31EX-21 50501 and up, D31PX-21 50501 and up, D37EX-21 5501 and up, D37PX-21 5501 and up, D39EX-21 1501 and up, D39PX-21 1501 and up
Technical Data:
- Engine model: Komatsu SAA4D102E-2-B diesel
- Number of cylinders: 4
- Piston displacement: 3.92 liters {3,920 cc}
- Rated horsepower: 56–71 kW {75–95 HP} at 2,000–2,200 rpm
- Final drive type: Planetary gear, 2-stage reduction, splash lubrication
- Hydraulic pump type: Fix displacement external-gear type
- Max. pump pressure: 20.6 MPa {210 kg/cm²}
- Operating weight range: 7,130–9,200 kg
- Travel speed (quick shift mode): 0.8–8.5 km/h (variable) or 3.4–8.5 km/h (quick shift)
Komatsu Manual Features & Content Preview
Technical Specifications and Data for Komatsu D31EX-21 through D39PX-21
This 745-page OEM factory publication (SEBM035005, printed November 2007) is the primary technical reference for component-level data across the D31, D37, and D39 series. It meticulously details the 2007 Komatsu D31EX-21, D31PX-21, D37EX-21, D37PX-21, D39EX-21, and D39PX-21 bulldozers powered by the SAA4D102E-2-B diesel engine.
If you need the data in the bay right now, the file is available as an instant download. It is fully searchable, allowing you to locate specific part numbers in seconds, and is laid out for standard letter and A4 printing. Your purchase remains securely stored in your account for easy retrieval in the event of a hard drive failure.
- 64 detailed structural diagrams
- 7 hydraulic system schematics
- 8 standard torque tables for maintenance reference
Component and System Architecture
This manual provides a structured breakdown of the machine's core systems. It details the functional specifications for the HST pump, planetary final drives, 3rd speed motors, and steering control assemblies. You get a clear view of the cooling systems, power trains, and HST hydraulic configurations. Evaluating heavy equipment for a major repair requires exact baselines. The maintenance sections deliver exact wear limits to help you determine if tracks, rollers, or pins are ready for replacement based on strict factory tolerances.
Specification Highlights and Reference Data
Precision matters in the shop. Technical highlights include specific taper screw torques for the 102 series engine and a 46 Nm torque setting for formatter board components. The document notes an engine displacement of 3.92 liters and sets the work equipment hydraulic system pressure at 20.6 MPa. Electrical systems are mapped out using AEX-rated wire codes. You will also find indexed fluid capacities and lubricant grades tailored for extreme cold and high-heat operations.
Working around pressurized hydraulics and massive track components presents inherent shop hazards. Thoroughly reviewing these factory pressure values and weight specifications helps technicians properly secure the machine and safely release system pressure before initiating any repairing procedures.
Customer Reviews
Read what our customers say about this Komatsu Bulldozer manual and share your own experience.