Engine R&R

Complete removal and reinstallation of the 5.9L Cummins I6 diesel engine from a 2007 Ram 3500 4WD, including disconnection of all systems, drivetrain separation, and engine extraction.

Warnings

Tools required

Parts

• Engine oil and filter × 1 — Use OEM specification
• Coolant (pre-mixed) × 1 — HOAT compatible
• Engine mount set × 1 — OEM or equivalent recommended
• Exhaust manifold gaskets × 1 — Use OEM specification
• Turbocharger mounting gaskets × 1 — Use OEM specification
• Intake manifold gaskets × 1 — Use OEM specification
• Oil filter adapter gasket × 1 — Use OEM specification
• Transmission-to-engine mounting bolts (reusable if not damaged) × 1 — Inspect for thread damage
• Various clamps and zip ties × 1 — Assorted sizes

Fluids

• 15W-40 diesel oil or 5W-40 synthetic — 12 qt
• HOAT coolant 50/50 — 28 qt

Preparation

1. Park vehicle on level concrete surface with adequate overhead clearance for engine hoist (minimum 8 feet)
2. Disconnect both battery cables, negative first, and remove batteries from engine bay for clearance
3. Drain engine oil completely and remove oil filter
4. Drain cooling system at radiator petcock and lower radiator hose
5. Have AC system evacuated by certified technician with refrigerant recovery equipment
6. Remove hood by marking hinge positions and unbolting with assistant
7. Cover fenders with protective blankets to prevent damage during procedure
8. Raise vehicle on jack stands to allow access underneath for transmission separation

Procedure

1. 1

   Remove air intake system and intercooler
   Remove the air filter housing and intake tubing from the turbocharger inlet. Disconnect charge air cooler (intercooler) tubes from the turbocharger outlet and intake manifold. Remove intercooler mounting bolts and set aside. Disconnect any vacuum lines attached to intake system and label for reassembly.
2. 2

   Disconnect cooling system components
   Remove radiator hoses (upper and lower) from engine. Disconnect heater hoses at firewall connections. Remove radiator fan shroud mounting bolts and lift shroud away with fan assembly intact if possible. If clearance requires, remove the mechanical fan clutch from water pump. Remove radiator mounting bolts and lift radiator assembly from vehicle. Disconnect coolant overflow reservoir and remove.
3. 3

   Disconnect fuel system
   Relieve low-pressure fuel supply at the fuel filter housing by loosening the bleed screw. Note: this is a high-pressure common rail system with rail pressures exceeding 23,000 psi; allow the system to fully depressurize and NEVER loosen any high-pressure line or fitting while the system is pressurized. Using appropriate fuel line disconnect tools, separate supply and return fuel lines at the fuel filter housing and the CP3 high-pressure injection pump. Note the CP3 feeds a high-pressure common rail; observe extreme caution with high-pressure lines and do not loosen high-pressure fittings until fully depressurized.. Cap all open fuel lines immediately to prevent contamination. On California emissions models, disconnect additional fuel vapor lines if equipped. Drain fuel filter housing if removing with engine.
4. 4

   Remove turbocharger and exhaust system
   Disconnect exhaust downpipe from turbocharger outlet at the clamp or flange. If equipped with a variable-geometry turbo (HE351VE), disconnect the VGT actuator electrical connector before removing the turbocharger. From underneath vehicle, remove exhaust pipe hangers and lower front exhaust section. Disconnect turbocharger oil drain tube at engine block. Disconnect turbocharger oil feed line from cylinder head. Remove turbocharger mounting nuts from exhaust manifold and remove turbocharger assembly. If reusing turbo, plug all openings to prevent debris entry.
5. 5

   Disconnect electrical connections
   Disconnect the engine wiring harness at the main connectors near the firewall or fender. Remove alternator wiring connections and mounting bolts, then remove alternator. Disconnect starter motor wiring and remove starter. Disconnect injection pump electrical connector at the CP3 fuel control actuator (FCA/MPROP) and disconnect the fuel rail pressure sensor connector. Remove camshaft position sensor connector (verify location per service manual for this engine). Disconnect grid heater relay and wiring if equipped. Disconnect all remaining sensors including coolant temperature, oil pressure, and crankshaft position sensor. Label all connections with tape flags.
6. 6

   Disconnect AC compressor and power steering
   If the AC system was evacuated per preparation, disconnect refrigerant lines from the compressor and cap all openings; otherwise remove AC compressor mounting bolts without disconnecting refrigerant lines and secure the compressor to the frame or radiator support with mechanic wire, ensuring no strain on lines. Remove power steering pump mounting bolts and secure pump aside with lines attached. If clearance is inadequate, power steering lines may be disconnected after marking positions, but cap all openings immediately to prevent contamination.
7. 7

   Remove intake manifold and accessories
   Note: this diesel engine has no throttle body or mechanical throttle linkage on the intake manifold (accelerator input is via the electronic APPS pedal sensor). Proceed to disconnect the grid heater and intake air heater wiring. Remove intake manifold grid heater (if equipped) by disconnecting wiring and removing mounting bolts. Remove intake manifold mounting bolts in sequence from outside to center. Lift the intake manifold (air intake/grid heater housing) and set aside. Cover intake ports with clean rags to prevent debris entry into cylinders.
8. 8

   Separate transmission from engine
   From underneath vehicle, remove transmission inspection cover to access torque converter bolts (automatic) or clutch/flywheel (manual). For automatic transmission, rotate crankshaft to access and remove all torque converter-to-flexplate bolts. Support transmission securely with transmission jack. Remove transmission-to-engine bellhousing bolts, noting different lengths and positions. For 4WD, ensure transfer case is also supported. Carefully slide transmission rearward to separate from engine, ensuring torque converter remains with transmission.
9. 9

   Remove engine mounts
   Support engine weight with engine hoist attached to factory lifting eyes or appropriate lifting brackets on cylinder head. Remove driver side engine mount through-bolt and bracket mounting bolts. Remove passenger side engine mount through-bolt and bracket mounting bolts. Inspect mount condition for replacement. Slightly raise engine with hoist to verify it is free from mounts before proceeding.
10. 10

    Final disconnections and engine removal
    Perform final walk-around inspection to verify all connections, hoses, wiring, and brackets are disconnected. Check that AC compressor and power steering pump are secured and clear of engine path. Attach engine leveler to hoist and adjust angle to clear firewall and radiator support. Slowly lift engine while guiding it forward and upward. The 5.9L Cummins is nose-heavy, so adjust leveler to maintain balance. Once clear of engine bay, lower onto engine stand or heavy-duty wooden cribbing. Never leave suspended engine unattended.

Reassembly

1. Clean all mating surfaces thoroughly, especially intake manifold, exhaust manifold, and transmission bellhousing faces
2. Inspect and replace engine mounts if showing signs of deterioration, cracking, or oil saturation
3. Install all new gaskets and seals; do not reuse old gaskets even if they appear intact
4. When reinstalling engine, reverse removal procedure ensuring transmission input shaft properly engages clutch disc (manual) or torque converter is fully seated in transmission pump (automatic)
5. Torque converter must be recessed into bellhousing approximately 1/2 inch before mating engine to transmission
6. Refill all fluids to proper levels: engine oil (12 qt), coolant (28 qt), and verify transmission fluid level after installation
7. Bleed air from fuel system at fuel filter housing before attempting to start
8. Prime oil system by cranking engine with fuel solenoid disconnected until oil pressure gauge shows pressure
9. Reconnect AC lines and have system recharged by certified technician
10. Double-check all electrical connections are secure and routing matches original configuration
11. Adjust drive belts to proper tension per service manual specifications

Verification

• Before starting, verify all fluid levels are correct and no leaks are present at drain plugs or filters
• Confirm all electrical connections are secure by gentle tug test
• Start engine and immediately verify oil pressure registers on gauge within 10 seconds
• Check for fuel, coolant, or oil leaks while engine idles; address immediately if found
• Verify cooling fan operates correctly and coolant circulates through system
• Test all accessories: alternator charging, AC compressor engagement, power steering operation
• Allow engine to reach operating temperature and verify thermostat opens (upper radiator hose becomes hot)
• Check for exhaust leaks at manifold and turbocharger connections
• Perform test drive to verify proper engine operation under load, transmission engagement, and no abnormal noises or vibrations
• Recheck all fluid levels after test drive and top off as necessary
• Inspect engine bay for any loose items, tools, or rags left behind during installation

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