M939 M939A1 M939A2 5-Ton 6×6 Truck Field Maintenance Manual TM 9-2320-272-23-3 Volume 3

Description

M939 M939A1 M939A2 5-Ton 6×6 Truck Field Maintenance Manual – Volume 3

This is the complete Volume 3 of the Field Maintenance Manual for the Truck, 5-Ton, 6X6, M939, M939A1, and M939A2 Series Trucks (Diesel). Published as TM 9-2320-272-23-3 (Air Force TO 36A12-1C-1155-2-3), this 1,472-page manual covers Chapter 8 maintenance instructions, providing the field-level maintenance procedures needed to keep these heavy-duty military trucks operational. It supersedes TM 9-2320-272-24-1 through 24-4 and TO 36A12-1C-1155-2-1 through 2-4, dated 30 June 1998.

File Details

• Manual Type: Field Maintenance Manual (Volume 3 of 5)
• Document Number: TM 9-2320-272-23-3 / TO 36A12-1C-1155-2-3
• Models Covered: M939, M939A1, M939A2 series 5-ton 6×6 trucks
• Language: English
• Page Count: 1,472
• File Format: PDF
• Date: 10 September 2012
• Distribution: Statement A – Approved for public release; distribution is unlimited

Chapters Covered

Volume 3 contains the following major maintenance work packages:

• Instrument cluster harness replacement
• Wiring harness repair
• Slave receptacle replacement
• Ground strap replacement
• Crane wiring harness replacement
• Front lights cable assembly replacement
• Front wiring harness replacement (M939/A1 and M939/A2)
• Rear wiring harness replacement
• Side marker lights wiring harness repair
• Transmission mount and bushing replacement
• Transmission oil service instructions
• Transmission dipstick tube and dipstick replacement
• Transmission mounting bracket and isolator replacement (M939A2)
• Transmission modulator and cable replacement
• Transmission neutral start switch replacement
• Governor piping and capacitor replacement
• Transmission selector shaft oil seal replacement
• Transmission select lever replacement
• Transmission shift tower replacement
• Transmission shift cable replacement
• Transmission replacement (out-of-vehicle and in-vehicle)
• Transmission oil pressure testing
• Transmission oil pan and filter replacement
• Transmission lubrication valve replacement
• Transmission fifth gear lock-in solenoid replacement
• Transmission oil cooler and mount replacement
• Transmission oil cooler filter and head repair
• Transmission oil cooler hoses replacement
• Transfer case replacement (all except M936/A1/A2 and M936/A1/A2)
• Transfer case speedometer drive gear and driven shaft replacement
• Transfer case front axle engagement control valve replacement
• Transfer case front axle lock-in control valve replacement
• Transfer case interlock air cylinder replacement
• Transfer case front axle engagement air cylinder replacement
• Front-wheel drive lock-in switch replacement
• Front wheel valve replacement and maintenance (M939A2)
• Transfer case interlock valve replacement
• Transfer case controls and linkage repair
• Transfer case capacitor replacement
• Transfer case transorb diode replacement
• Transfer case oil pump replacement
• Forward-rear to rear-rear propeller shaft replacement
• Transfer case to forward-rear axle propeller shaft repair
• Transfer case to front axle propeller shaft repair
• Transmission to transfer case propeller shaft repair
• Front axle replacement
• Front axle breather replacement
• Front and rear axle carrier differential replacement
• Front differential oil seal replacement
• Front axle drive companion flange replacement
• Steering knuckle boot replacement
• Front axle seal replacement
• Front axle shaft and universal joint replacement
• Steering knuckle repair
• Spindle bearing sleeve replacement
• Forward-rear and rear-rear axle replacement
• Forward-rear and rear-rear axle leakage test
• Rear axle breather replacement
• Rear axle shaft replacement
• Rear differential oil seal replacement
• Carrier differential top cover gasket and side cover gasket replacement
• Parking brake adjustment
• Parking brake cable and bracket replacement
• Parking brake shoes replacement
• Parking brake drum dust cover replacement
• Wheel brake drum dust covers replacement
• Parking brake lever replacement
• Brake shoe replacement
• Front brake spider and actuator repair
• Rear brake spider and actuator repair
• Brake pedal (treadle) valve replacement
• Spring parking brake valve repair
• Brake mechanism adjustments
• Brake pedal replacement
• Service brake chamber replacement
• Combination spring (emergency) and service brake chamber replacement
• Air governor replacement
• Air reservoir one-way check valve replacement
• Brake chamber air manifold tee replacement
• Front limiting valve replacement
• Primary air reservoir (supply tank) replacement
• Secondary air reservoir (supply tank) replacement
• Wet air reservoir (supply tank) and bracket replacement
• Wet air reservoir and mounting plate replacement (M936/A1/A2)
• Emergency spring brake (supply tank) air reservoir replacement
• Brake proportioning valve replacement
• Air reservoir drain valves replacement
• Fan drive clutch actuator replacement (M939/A1)
• Fan clutch actuator replacement
• Spring brake dash control valve replacement
• Air couplings replacement
• Wet reservoir (supply tank) safety valve replacement
• ABS electronic control unit (ECU) replacement
• ABS double check valve No. 5, No. 6, and No. 7 replacement
• Brake LQ-2 valve replacement
• Rear ABS relay valve replacement
• Forward ABS relay valve with ECU replacement
• Inversion valve replacement
• Air supply line safety valve replacement
• Governor control air line replacement
• Air line cross fitting replacement
• ABS 3-amp fuse and Y lead connector replacement
• ABS 15-amp fuse and jumper lead replacement
• ABS ground jumper lead replacement
• ABS indicator lamp replacement
• ABS ECU main wiring harness replacement
• ABS wheel sensor and bracket replacement
• Rear ABS relay exciter ring replacement
• Air compressor and lines replacement (M939A2)
• Air compressor coolant lines replacement (M939A2)
• Trailer airbrake hand control valve replacement (M931/A1/A2, M932/A1/A2)
• Double check valve No. 1 through No. 5 replacement
• Emergency and trailer coupling hoses replacement
• Front hub and drum replacement (M939/A1)
• Rear hub and drum replacement (M939/A1)
• Front hubs replacement
• Rear hubs replacement (M939A2)
• Wheel bearing adjustment
• Wheel and tire rotation/replacement (M939 and M939A1/A2)
• Wheel valve filter replacement (M939A2)
• Hub air seal leak test
• Rear axle air manifold replacement
• Wheel valve repair (70 PSI M939A2)
• Front wheel valve maintenance (M939A2)
• Rear wheel valve repair (M939A2)
• Drag link replacement
• Tie rod and toe-in check/repair
• Upper and lower steering column repair
• Steering wheel replacement
• Pitman arm replacement (Ross and Sheppard)
• Steering stop adjustment
• Steering gear stone shield replacement
• Steering gear and mounting bracket replacement (Ross and Sheppard)
• Power steering pump filter and reservoir replacement (M939A2)
• Power steering pump replacement (M939/A1)
• Steering pump drivebelts replacement (M939/A1)
• Power steering pump pressure and return hoses replacement (Ross and Sheppard)
• Steering assist cylinder hoses replacement
• Steering gear-to-assist cylinder pressure lines replacement
• Power steering gear stop adjustment (on-vehicle)
• Steering assist cylinder replacement
• Steering assist cylinder stone shield replacement
• Front and rear lifting shackle and bracket replacement
• Rear cab improved crossmember replacement
• Front and rear field chock anchors replacement (M936/A1 wrecker)
• Bumperette replacement
• Front bumper and plates replacement
• Vehicle tiedown component replacement
• Pintle hook repair
• Van davit chain and wire rope replacement
• Van swing davit and pulley replacement
• Van davit winch replacement (M934A1/A2)
• Tractor spare tire carrier replacement (M931 and M932)
• Tractor spare tire carrier and toolbox replacement (M931A1/A2 and M932A1/A2)
• Dump and tractor spare tire carrier access step replacement
• Dump and van spare tire carrier replacement
• Cargo spare tire carrier replacement
• Cargo spare tire carrier access step replacement
• Tractor fifth wheel (Dayton/Walter) removal
• Fifth wheel approach plates replacement
• Fifth wheel deck plate replacement
• Fifth wheel spacers replacement
• Front spring and main leaf repair
• Front spring shackle and shackle hanger replacement
• Front spring bushing replacement
• Front spring bumper replacement
• Rear spring bumper replacement
• Rear spring repair
• Rear spring seat repair
• Rear axles spring seat wear pads and upper bracket replacement
• Cross tube replacement
• Shock absorber and mounting pins replacement
• Upper and lower torque rod replacement
• Cab door replacement
• Outside door handle replacement
• Cab door dovetail wedge replacement
• Cab door dovetail replacement
• Cab door weather seal replacement
• Cab door inspection hole cover replacement
• Cab door lock replacement
• Cab door glass replacement
• Window weather stripping (cab door) replacement

This is a genuinely massive field maintenance manual that covers nearly every mechanical, electrical, air, hydraulic, and structural system on the M939 series trucks. Whether you’re replacing a wiring harness, rebuilding a brake actuator, pulling a transmission, or adjusting a steering gear, the procedures in this volume walk through each step with detailed illustrations and callouts.

What This Manual Enables You to Do

The M939 series trucks are complex machines with air brakes, CTIS (Central Tire Inflation System on A2 models), ABS, power steering, and a host of other systems. This manual gives you the exact procedures for:

• Removing and installing major components like the transmission, transfer case, axles, and steering gear
• Servicing and adjusting brakes, including parking brake, service brakes, and spring brakes
• Repairing air systems, including reservoirs, valves, compressors, and governors
• Troubleshooting and replacing ABS components
• Replacing wiring harnesses throughout the vehicle
• Servicing the CTIS wheel valves and air seals
• Maintaining the suspension system, including springs, shackles, and torque rods
• Replacing cab doors, windows, locks, and weather seals
• Working on the fifth wheel, spare tire carriers, and towing components

Each procedure includes initial setup information (tools needed, materials required, equipment condition), step-by-step removal and installation instructions, and detailed illustrations with numerical callouts. Follow-on maintenance tasks are listed so you know what needs to be done after a component is replaced.

Why Getting the Right Manual Matters

These aren’t simple vehicles. A 5-ton 6×6 military truck has systems you won’t find on civilian vehicles – CTIS, air-over-hydraulic brakes, spring brake chambers, and a complex transfer case with interlock and engagement controls. Using the wrong procedure, guessing at torque values, or skipping a critical adjustment step can lead to equipment damage or, worse, an unsafe vehicle.

The procedures in this manual give you the correct sequence, the right torque values, and the proper adjustments. Whether you’re a unit mechanic, a fleet operator, or an enthusiast maintaining a privately-owned M939 series truck, having the field maintenance manual for the exact model you’re working on is essential.

Instant PDF Access

This 1,472-page manual is delivered as a PDF that you can view on any device – computer, tablet, or smartphone. You can print the pages you need for the job at hand, or keep the entire manual on a laptop or tablet in the shop. No waiting for a physical book to ship, no missing pages, no torn covers. You get the complete Volume 3 as published, ready to use immediately after purchase.