M878A2 Yard Tractor Unit Direct Support General Support Maintenance Manual TM 9-2320-312-24-3

Description

File Details

• Manual Type: Unit, Direct Support, and General Support Maintenance Manual
• Document Number: TM 9-2320-312-24-3
• Change Number: Change 1
• Change Date: 2 September 2005
• Original Date: 17 December 2003
• Language: English
• Page Count: 866
• File Format: PDF
• Equipment Covered: Truck, Tractor, Yard Type: 46,662 GVWR, DED, 4×2, M878A2
• NSN: 2320-01-452-5579

What This M878A2 Yard Tractor Maintenance Manual Covers

This M878A2 Yard Tractor Unit Direct Support General Support Maintenance Manual TM 9-2320-312-24-3 is the complete technical publication for maintaining the M878A2 yard tractor. It combines military work-package procedures with commercial off-the-shelf service manuals for the major components installed on this tractor. The manual spans three volumes and covers everything from introductory theory to unit maintenance, direct support maintenance, general support maintenance, and supporting information including references and the Maintenance Allocation Chart.

The M878A2 is equipped with the Allison MD 3560P transmission, and this manual contains the full Allison Transmission Service Manual SM2148EN covering overhaul, disassembly, module rebuild, assembly, wear limits, spring data, and troubleshooting for that transmission. Also included is the Allison Transmission Troubleshooting Manual covering WTEC III electronic controls, diagnostic codes, wire check procedures, oil level sensor operation, input/output functions, and performance complaint troubleshooting.

For the front axle, the manual contains the Dana Spicer Steer Axles Service Manual for the E1460I model, covering inspection procedures, knuckle vertical play, bushing inspection, tie rod inspection and replacement, wheel alignment including camber, caster, and toe settings, steering stop adjustment, kingpin bushing and seal replacement, and wheel bearing adjustment. The Dana Spicer Brakes Service Manual covers the ES165-5D brake model with drum removal, shoe removal, brake adjuster removal, camshaft removal, air chamber bracket removal, spider removal, dustshield removal, cleaning, inspection, repair, replacement, and installation procedures.

The rear axle coverage includes the D90-14-2S drive axle with Spicer S cam brakes, covering lubrication, routine maintenance, hub reduction unit service, brake shoe removal and rebuilding, brake bracket and camshaft assembly and re-assembly, hub and annulus re-assembly, setting hub bearings, planet carrier assembly, drive head unit service including differential dismantling and spiral bevel pinion unit, and gear identification and mesh checking for both Gleason and Oerlikon gear types.

Steering system coverage includes the M-Series Power Steering Service Manual, covering operating principles, diagnosis and troubleshooting, preventive maintenance, input shaft seal replacement, sector shaft seal replacement, bleeding single and dual steering gear systems, axle stop adjustment, manual and automatic relief plunger adjustment and repair, pitman arm removal and installation, and complete disassembly and reassembly procedures.

The manual also includes the Crane Carrier Propshaft Manual covering inspection, maintenance, lubrication, U-joint removal and replacement, and troubleshooting; the Espar Hydronic 10 Water Heater installation, troubleshooting, and parts manual covering heater location, mounting, plumbing, fuel system, electrical connections, exhaust and intake connections, operating switches, heater operation, maintenance, troubleshooting, fault codes, repair steps, resistance values, and fuel quantity testing; the Crane Carrier Air System Manual covering system description, maintenance, check procedures, and troubleshooting; the Meritor WABCO System Saver Series Single Cartridge Air Dryers Maintenance Manual covering troubleshooting, testing, and replacement of desiccant cartridge, outlet check valve, heater assembly, turbo cut-off valve, regeneration valve, purge valve, pressure-controlled check valve, pressure relief valve, and purge silencer; the Holland Fifth Wheel repair kit instructions and troubleshooting guide covering difficult coupling and uncoupling, excessive kingpin movement, pin rising, and hard steering or binding; and the N1509 Series Troubleshooting Guide for N1509-1 Alternators covering wiring diagrams, basic troubleshooting, and advanced troubleshooting including battery conditions, charge volt and amp values, and regulator diagnostics.

Chapters and Sections Covered

• Warning Summary
• General Information and Theory of Operation
• Troubleshooting Procedures
• Unit Maintenance
• Direct Support Maintenance
• General Support Maintenance
• Supporting Information including References, Maintenance Allocation Chart, Expendable and Durable Items List, and Tool Identification List
• Allison Transmission MD 3560P Service Manual
• Allison Transmission Troubleshooting Manual (WTEC III)
• Dana Spicer Steer Axles Service Manual (E1460I)
• Dana Spicer Brakes Service Manual (ES165-5D)
• Spicer Speciality Axle Division D90-14-2S Drive Axle Service Manual
• Sheppard M-Series Power Steering Service Manual
• Crane Carrier Propshaft Manual
• Espar Hydronic 10 Water Heater Installation, Troubleshooting, and Parts Manual
• Crane Carrier Air System Manual
• Meritor WABCO System Saver Series Single Cartridge Air Dryers Maintenance Manual
• Holland Fifth Wheel Repair Kit Instructions and Troubleshooting Guide
• N1509 Series Troubleshooting Guide for N1509-1 Alternators

This M878A2 Yard Tractor maintenance manual gives a technician the complete set of procedures, specifications, and diagnostic information needed to service, repair, and overhaul the tractor and its major assemblies. The document is structured so that unit-level maintenance can be performed using basic hand tools, while direct support and general support maintenance sections provide the deeper disassembly, inspection, and rebuild procedures for the transmission, axles, brakes, steering gear, and other systems. Each commercial service manual included in this publication retains its original formatting and specifications, giving the reader access to the same information a dealer technician would use.

Who This Manual Is For

This manual is intended for military maintenance personnel, fleet mechanics, and independent technicians responsible for the M878A2 yard tractor. It is also valuable for owners and operators who want to understand the systems on their equipment and perform their own maintenance or repairs. Because the manual covers multiple component manufacturers and includes both military work-package instructions and commercial service procedures, it serves as a single reference for the entire tractor rather than requiring separate publications for each assembly.

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Why This M878A2 Yard Tractor Maintenance Manual Matters

The M878A2 Yard Tractor is a specialized piece of equipment used for spotting and moving trailers in freight yards, rail terminals, and distribution centers. Keeping it operational requires correct maintenance and timely repair of its transmission, axles, brakes, steering, air system, and electrical components. This manual provides the exact procedures and specifications needed to perform those tasks correctly. Using the wrong torque value, clearance, or adjustment procedure can lead to premature failure, unsafe operation, or damage to expensive components.

The troubleshooting sections in this manual are particularly valuable because they help diagnose problems systematically rather than by trial and error. The Allison transmission diagnostic code charts, the air system check procedures, the brake troubleshooting, and the power steering diagnosis all guide the technician through logical steps to identify the root cause of a problem. This saves time and reduces the risk of replacing parts that are not actually faulty.

The exploded views, cross-section illustrations, and wiring diagrams throughout the manual provide visual guidance for assembly and disassembly. The transmission foldouts, axle exploded views, brake component illustrations, and hydraulic schematics make it easier to understand how components fit together and how systems operate.

Get Instant Access

This M878A2 Yard Tractor Unit Direct Support General Support Maintenance Manual TM 9-2320-312-24-3 is delivered as an instant PDF download after payment. No shipping, no waiting. The file can be viewed on any device including computers, tablets, and smartphones, and can be printed for use in the shop or vehicle. With 866 pages of maintenance procedures, specifications, and diagnostic information covering the complete tractor and all major components, this manual enables you to perform unit maintenance, direct support maintenance, and general support maintenance on the M878A2 yard tractor with confidence.