Komatsu D40A-1, D40P-1, D45A-1, D45P-1, D45S-1 Shop Manual

Komatsu D40A-1 through D45S-1 Bulldozer Technical Documentation

• Built for owners and workshops maintaining the 1978 Komatsu D40A-1, D40P-1, D45A-1, D45P-1, and D45S-1 bulldozer series with S4D105 diesel engine variants
• Original OEM publication D40,45.1-BE2, first issue 1978
• Contains 47 detailed exploded-view diagrams and 16 system-specific performance/capacities reference tables
• File delivered as a direct download the moment payment clears
• Permanent availability in your purchase account — no re-buy required
• Laid out for standard letter and A4 printing
• Full-text search finds any part number in seconds
• This 966-page volume provides the official factory standards for identifying chassis and engine serial number ranges during overhaul procedures

Operational Architecture and Component Details

This 1978 Komatsu D40A-1 and D45A-1 service manual covers the complete technical scope of the bulldozer fleet, documenting the S4D105 engine, Torqflow drivetrain, and hydraulic control systems. The publication provides detailed construction summaries, maintenance standards, and assembly procedures for the crawler frame, steering case, and gear pump assemblies. Technicians can access exploded-view diagrams for engine disassembly, turbocharger servicing, and fuel injection pump calibration. Additional sections clarify correct procedures for undercarriage maintenance, including track tensioning and sprocket wheel segment replacement.

Engine and Hydraulic Specification Preview

The Komatsu D45A-1 engine performance curves specify a rated output of 90 PS at 2400 rpm. The Komatsu D40P-1 fuel tank capacity is documented at 210 liters in the fluid summary table. Oil pump regulator cracking pressure for the S4D105-1 engine is specified at 3.9–4.4 kg/cm² in the lubrication section. The manual includes specific fluid capacity charts for D45S-1 models, listing engine cooling water at 35 liters. This official Komatsu OEM workshop manual covers the 1978 D40/D45 bulldozer series, documenting engine, drivetrain, and hydraulic specifications required for machine maintenance and component overhaul.