🏷️ Basic Information Identification Make: AM General Model: M939 Series (and variants) Codes Chassis Codes: M923, M923A1, M924, M924A1, M925, M925A1, M926, M926A1, M927, M927A1, M928, M928A1, M929, M929A1, M930, M930A1, M931, M931A1, M932, M932A1, M934, M934A1, M935, M935A1, M936, M9361 👋 Introduction Market Position Target Audience: Military vehicle mechanics, fleet maintenance personnel, civilian operators of M939 series trucks Key Features Documentation Origin: Public domain U.S. Government manual, not copied from other CD-ROM products File Size And Organization: 60MB file, consolidating 4 volumes into a single searchable PDF 📋 Manual Details Coverage Areas Primary Coverage: Unit Maintenance (Preventive Maintenance Checks & Services, Troubleshooting, Systems Maintenance & Repair) Page Count Total Pages: 3600+ Manual Type Type: Service Repair Manual Language Language: English Format Format: PDF (4 volumes in 1) 📖 Manual Coverage Systems Covered Mechanical Systems: Engine, Transmission, Drivetrain (Propeller Shafts, Axles), Suspension, Brakes, Steering, Cooling, Fuel, Exhaust, Air Intake Electrical Systems: Wiring Diagrams, Lighting, Starting System, Charging System, Instrumentation, Control Systems Procedures Included Maintenance Procedures: Preventive Maintenance Checks and Services (PMCS), Lubrication Schedules, Fluid Level Checks, Filter Replacements Troubleshooting Procedures: Mechanical Systems Troubleshooting, Electrical Systems Troubleshooting, Diagnostic Flowcharts Repair Procedures: Component Removal and Installation, Overhaul Procedures, Adjustments, Calibration Technical Depth Depth: Comprehensive unit maintenance and repair, suitable for field service and workshop personnel 📊 Manual Specifications File Format Digital Format: PDF (Portable Document Format) Print Quality Illustrations: Numerous high-quality illustrations, line drawings, and exploded views Binding Type Binding: N/A (Digital Format) Paper Type Paper Quality: N/A (Digital Format) ⚙️ Engine Specifications Primary Engine Engine Model M939 M939A1: Cummins NHC-250 Engine Model M939A2: Cummins 6CTA8.3 Turbo-Diesel Performance Displacement Nhc 250: 14 Liters Configuration Nhc 250: Inline 6-Cylinder Diesel Fuel System Fuel Type: Diesel Maintenance Recommended Oil Type: Refer to manual for specific API service categories and viscosity grades (e.g., SAE 15W-40 for diesel engines) 🔧 Transmission Standard Transmission Type: Allison Automatic Features Number Of Speeds: 5-Speed Automatic with 2-Speed Transfer Case Maintenance Transmission Fluid Type: Allison TES-295 approved fluids (e.g., Dexron III/Mercon or equivalent) 📐 Dimensions Exterior Length M939A2: 7,890 mm (310.6 inches) Width M939A2: 2,470 mm (97.2 inches) Height M939A2: 3,070 mm (120.9 inches) Weights Curb Weight M939A2: 9,027 kg (19,901.1 lbs) Chassis Drive Layout: 6x6 All-Wheel Drive 🛡️ Safety Features Ratings Crash Test Ratings: N/A (Military Vehicle - Not subject to civilian crash testing standards) Active Features Braking System: Air Brakes (Service and Parking) Passive Features Cab Construction: Heavy-duty steel construction designed for extreme environments and load-bearing 💡 Technology Features Infotainment Infotainment System: Basic instrumentation for operational monitoring (e.g., speedometer, tachometer, engine vitals, warning lights). No modern infotainment features. Driver Assistance Driver Assistance Features: None. Designed for raw utility and operational capability, not modern driver assistance. Connectivity Connectivity Options: None. Military communication systems may be integrated separately. 🔧 Maintenance Service Intervals Engine Oil Change: Refer to manual; typically based on mileage or operating hours (e.g., 3,000-5,000 miles or 250 hours) Transmission Fluid Service: Refer to manual; typically based on mileage or operating hours and operating conditions (e.g., 20,000-50,000 miles) Fluid Specifications Engine Coolant: Ethylene Glycol based coolant, typically 50/50 mix with distilled water. Specific type (e.g., heavy-duty diesel coolant) and additive requirements are detailed in the manual. Differential And Axle Fluid: GL-5 rated gear oil, appropriate viscosity (e.g., 80W-90 or 85W-140) depending on ambient temperature. Refer to manual for exact specifications and capacities. Known Issues Common Wear Items: Brake components (shoes, drums, air lines), suspension bushings, universal joints, exhaust system components, cooling system hoses and radiators, engine accessory belts and hoses. Troubleshooting Tips Engine Starting Issues: Check battery charge, glow plug operation, fuel system integrity, air intake restrictions, and starter motor engagement. Transmission Shifting Issues: Verify transmission fluid level and condition, check for air leaks in the pneumatic control system, and diagnose solenoid or hydraulic issues. 📚 Vehicle History Brand Heritage Manufacturer: AM General (initial production), BMY (later production and M939A2 variants) Model Evolution Series Development: Successor to the M35 series, designed for increased payload and improved performance Production Production Start: 1982 Production Update: M939A1 series updated variants, M939A2 series production began 1989 🏆 Awards & Recognition Recognitions Military Service: Widely adopted and deployed by the United States Armed Forces and allied nations due to its robustness and versatility.