Engine R&R

Complete removal and reinstallation of the 5.9L Cummins I6 diesel engine from a 1994-2007 Dodge Ram 2500 4WD, including disconnection of all accessories, drivetrain separation, and engine lifting procedures.

Warnings

Tools required

Parts

• Engine oil and filter × 1 — Use OEM specification
• Coolant (green conventional or HOAT depending on year) × 1 — Use OEM specification
• Oil drain plug crush washer × 1 — Use OEM specification
• Exhaust manifold gaskets × 1 — Use OEM specification
• Intake manifold gaskets × 1 — Use OEM specification
• Turbocharger mounting gasket × 1 — Use OEM specification
• Transmission-to-engine gasket or seal × 1 — Use OEM specification
• Engine mount hardware (inspect and replace as needed) × 1 — Use OEM specification
• Anti-seize compound × 1 — High-temperature rated
• Thread locker (medium strength) × 1 — Loctite 242 or equivalent

Fluids

• 15W-40 diesel engine oil — 12 qt
• Ethylene glycol 50/50 coolant — 28 qt
• Mopar ATF+4 (power steering) — 2.5 qt

Preparation

1. Park vehicle on level concrete surface and engage parking brake. Chock rear wheels securely.
2. Disconnect both battery cables (negative first, then positive) and remove battery.
3. Drain engine oil completely and replace drain plug with new crush washer.
4. Drain cooling system from radiator petcock and block drain plugs. Collect coolant in appropriate containers.
5. Recover AC refrigerant using approved equipment or have system professionally evacuated.
6. Remove hood by marking hinge positions and unbolting with assistant support.
7. Remove radiator shroud, cooling fan assembly, and radiator.
8. Relieve fuel system pressure by loosening fuel filter drain valve or disconnecting fuel pump relay and cranking engine.
9. Raise front of vehicle and support on jack stands at frame rails. Ensure vehicle is stable.
10. Remove front skid plate (if equipped) and drain front differential if access is required.

Procedure

1. 1

   Disconnect electrical and sensor connections
   Label and disconnect all engine electrical connections including: alternator wiring, starter solenoid wiring, oil pressure sender, coolant temperature sensors, fuel injection pump wiring harness (typically on driver side of pump), grid heater relay, transmission control connections as equipped (e.g., 47RE/48RE governor pressure sensor and transmission range sensor, or TV/kickdown cable on earlier automatics), and any chassis ground straps attached to engine block. Photograph connections before removal for reference.
2. 2

   Remove air intake and intercooler system
   Remove air filter housing and intake tubing. Disconnect intercooler piping from turbocharger outlet and intake manifold. Remove intercooler boots and clamps. On some models, the intercooler may need to be removed from its mounting brackets. Disconnect the crankcase breather/ventilation tube from the valve cover (open breather system on most years; no PCV connection to intake).
3. 3

   Disconnect fuel system
   Using line wrenches to prevent damage, disconnect fuel supply line from fuel filter housing and fuel return line from injection pump. Cap all open fuel lines immediately to prevent contamination. Disconnect fuel heater wiring if equipped. Remove fuel filter housing from bracket if it interferes with engine removal.
4. 4

   Remove accessory drive components
   Remove serpentine belt by releasing tensioner. Unbolt and remove AC compressor, setting it aside with lines still attached (support with wire, do not let hang by hoses). Remove alternator and set aside. Remove power steering pump and secure aside with hoses attached. Disconnect vacuum pump if equipped.
   Torque spec

   AC Compressor Bolts25 Nm (18 lb-ft)

   Alternator Mounting Bolts50 Nm (37 lb-ft)

   Power Steering Pump Bolts25 Nm (18 lb-ft)
5. 5

   Disconnect exhaust system
   From underneath vehicle, disconnect exhaust downpipe from turbocharger outlet. Remove exhaust manifold-to-turbo connection if necessary for clearance. Apply penetrating oil to exhaust fasteners 24 hours before removal if possible to ease removal. Support exhaust system to prevent damage.
6. 6

   Disconnect cooling system hoses
   Remove upper and lower radiator hoses from engine. Disconnect heater hoses at firewall connections. Remove coolant bypass hose if present. Disconnect overflow tank hose. Ensure all coolant is drained before hose removal to minimize spillage.
7. 7

   Separate transmission from engine
   Support transmission with transmission jack positioned at center of transmission pan. Remove transmission-to-engine bellhousing bolts (verify count and locations against the service manual for your specific transmission — NV4500/NV5600/G56 manual or 47RH/47RE/48RE automatic). Disconnect transmission cooler lines if automatic. Disconnect the hydraulic clutch slave cylinder/line if manual transmission (these use a hydraulic clutch, not mechanical linkage). Carefully slide transmission rearward approximately 2 inches to disengage input shaft from clutch/torque converter, then lower transmission slightly and support securely.
   ⚠Transmission must be properly supported before removing bellhousing bolts. Transmission weighs 200+ lbs and can cause injury if it falls.
   Torque spec

   Transmission-to-Engine Bolts55 Nm (41 lb-ft)
8. 8

   Remove starter motor
   Remove starter mounting bolts and carefully extract starter from bellhousing. Disconnect starter wiring if not already done. Set starter aside in safe location.
   Torque spec

   Starter Mounting Bolt50 Nm (37 lb-ft)
9. 9

   Disconnect throttle and cruise control cables
   Disconnect throttle cable from throttle lever on injection pump (P7100 mechanical pump, 1994-1998). Note: VP44 (1998.5-2002) uses an electronic APPS (accelerator pedal position sensor) via the throttle linkage, and CR common-rail engines (2003-2007) use a fully electronic accelerator pedal with no throttle cable — disconnect the APPS/pedal connector as applicable rather than a cable. Disconnect cruise control cable if equipped. Remove cable brackets from valve cover or intake manifold as needed for clearance.
10. 10

    Prepare engine for lifting
    Attach engine leveler to engine hoist chain. Install lifting chains or hooks to the factory engine lift eyes (verify exact locations on your engine before lifting — the 5.9L Cummins has cast/bolted lift brackets; confirm positions in the service manual). Ensure lifting points are secure and rated for engine weight. Take up slack in hoist chain until tension is felt but engine mounts are still supporting weight.
    ⚠️Verify all lifting hardware is rated for minimum 1500 lbs. Inspect chains and hooks for wear or damage before lifting.
11. 11

    Remove engine mounts
    Remove engine mount-to-frame bolts on both driver and passenger sides. Then remove engine mount-to-block bolts. The 5.9L Cummins uses frame-mounted engine mounts with through-bolts. Engine may need to be raised slightly to relieve tension on mounts. Keep mount hardware organized for reinstallation.
    ⚠Engine will shift when mounts are removed. Ensure hoist is taking full weight before removing final mount bolts.
    Torque spec

    Engine Mount-to-Block Bolts65 Nm (48 lb-ft)

    Engine Mount-to-Frame Bolts75 Nm (55 lb-ft)
12. 12

    Final inspection and engine removal
    Perform final walkthrough inspection to ensure all connections, hoses, wires, and mounting points are disconnected. Check underneath engine for any remaining attachments. Slowly raise engine with hoist while adjusting engine leveler to maintain balance. Tilt engine slightly nose-up to clear transmission input shaft and bellhousing. Continue raising while guiding engine forward and up, clearing radiator support and front crossmember. Use assistant to watch clearances and guide engine. Once clear of vehicle, lower onto engine stand or secure wooden blocks.
    ⚠️Move slowly and deliberately. Engine should lift smoothly - any binding indicates a missed connection. Stop immediately and investigate if resistance is felt.

Reassembly

1. Installation is reverse of removal with the following critical notes:
2. Clean all gasket mating surfaces thoroughly on exhaust manifolds, turbo connections, and transmission bellhousing before reassembly.
3. Install new gaskets on exhaust manifolds, intake connections, and turbocharger mounting surfaces.
4. Apply anti-seize compound to exhaust manifold studs and nuts before installation per torque specification notes.
5. When lowering engine into chassis, align engine mounts carefully and use transmission jack to align transmission input shaft with clutch disc or torque converter pilot.
6. Torque all fasteners in specified sequence: engine mounts first, then transmission bellhousing bolts in star pattern, then all accessory mounting bolts per specifications.
7. Double-check that flywheel bolts (if removed) are torqued in star pattern and replace if TTY type.
8. Reconnect all electrical connections per photos/labels taken during disassembly. Verify all ground straps are reinstalled.
9. Refill cooling system with proper coolant mixture (28 quarts total capacity). Burp cooling system per manufacturer procedure to remove air pockets.
10. Fill engine with 12 quarts of 15W-40 diesel engine oil and new filter.
11. Refill power steering system and bleed air by turning steering lock-to-lock with engine running.
12. If AC system was disconnected, evacuate and recharge system to proper R-134a specification.
13. Reinstall radiator, fan assembly, shroud, and hood (align hood to marked positions).

Verification

• Before starting engine, rotate crankshaft by hand two full revolutions using breaker bar on harmonic balancer bolt to ensure no internal binding or interference.
• Verify oil pressure gauge shows pressure within 5 seconds of startup. Normal oil pressure is 10 psi at idle when warm, 30-60 psi at operating RPM.
• Check for fuel, oil, coolant, and exhaust leaks while engine is running. Look carefully at all connection points.
• Verify all gauges are functioning: coolant temperature, oil pressure, charging system voltage (13.8-14.4V with engine running).
• Test all electrical accessories: lights, gauges, HVAC blower, AC compressor engagement.
• Allow engine to reach operating temperature (approximately 180-195°F) and verify cooling fans cycle properly.
• Check transmission fluid level with engine running (automatic) or in neutral (manual) and top off as needed.
• Perform test drive to verify proper engine performance, transmission shifting, no abnormal noises or vibrations.
• Recheck all fluid levels after test drive and inspect underneath vehicle for any new leaks.
• Retorque cylinder head bolts if they were disturbed (this requires valve cover removal and specific torque sequence - consult service manual).

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