Exhaust Manifold

This procedure covers the removal and replacement of the exhaust manifold on a 2007 Ram 3500 with the 5.9L Cummins diesel engine, including turbocharger disconnection and associated components.

Warnings

Tools required

Parts

• Exhaust manifold gasket × 1 — Use OEM specification
• Exhaust manifold to turbo gasket × 1 — Use OEM specification
• Exhaust manifold studs × 12 — Use OEM specification - inspect and replace as needed
• Turbocharger mounting nuts × 6 — Use OEM specification
• Exhaust manifold nuts × 12 — Use OEM specification
• Oxygen sensor anti-seize compound × 1 — Use OEM specification

Preparation

1. Ensure engine is completely cool to the touch
2. Disconnect both batteries (negative terminals first)
3. Raise vehicle and support securely on jack stands
4. Apply penetrating oil to all exhaust manifold studs, turbo mounting nuts, and oxygen sensor threads. Allow to soak for at least 30 minutes (24 hours preferred)
5. Remove engine cover if equipped
6. Drain coolant if removing EGR cooler connections

Procedure

1. 1

   Remove intake system components
   Remove the air intake tube from the turbocharger inlet. Disconnect and remove the air filter housing assembly to gain access to the turbocharger and exhaust manifold area. Label any vacuum lines or electrical connections before disconnecting.
2. 2

   Disconnect turbocharger oil lines
   Locate the turbocharger oil feed line at the top of the turbo and the oil drain tube at the bottom. Remove the banjo bolt securing the oil feed line and cap or plug the openings immediately to prevent contamination. Remove the oil drain tube bolts and carefully separate the drain tube from the turbocharger and engine block. Inspect o-rings and gaskets for replacement.
   ⚠Oil will drain from these lines. Have a drain pan ready and plug all openings immediately to prevent dirt entry.
3. 3

   Remove exhaust downpipe
   From underneath the vehicle, locate the V-band clamp or bolted flange connection between the turbocharger outlet and the exhaust downpipe. Loosen and remove the clamp or mounting bolts. Separate the downpipe from the turbocharger and support it with wire or a strap to prevent damage.
4. 4

   Disconnect EGR and intake components
   If equipped with EGR, disconnect the EGR valve from the exhaust manifold. Remove mounting bolts and separate the EGR tube. Disconnect any intake grid heater wiring or other components attached to the intake manifold that may interfere with exhaust manifold removal.
5. 5

   Remove oxygen sensor
   Using an oxygen sensor socket, carefully remove the oxygen sensor from the exhaust manifold. If the sensor is seized, apply additional penetrating oil and allow to soak. Apply gentle heat if necessary but avoid excessive force to prevent thread damage in the manifold.
   ⚠Do not contaminate oxygen sensor tip with oil or grease. Handle only by the connector body.
6. 6

   Remove turbocharger mounting nuts
   Remove the six nuts securing the turbocharger to the exhaust manifold. These are typically 15mm nuts. Work carefully as studs may break if seized. Once all nuts are removed, carefully pull the turbocharger away from the manifold studs and remove it from the vehicle. Support the weight of the turbo during removal.
   ⚠Turbocharger weighs approximately 25-30 lbs. Use proper lifting technique and have an assistant if needed.
7. 7

   Remove exhaust manifold nuts
   Working from front to back, remove all twelve nuts securing the exhaust manifold to the cylinder head. Use a systematic pattern and be prepared for broken studs. If a stud breaks, mark its location for later extraction. Keep track of any washers or spacers.
   ⚠Studs commonly break on this engine. Have stud extractors available and plan additional time if extraction is needed.
8. 8

   Remove exhaust manifold
   Carefully work the exhaust manifold away from the cylinder head studs. The manifold is heavy and may be stuck to the head with carbon buildup. Use a pry bar if necessary but avoid damaging the cylinder head surface. Once free, lift the manifold away from the engine bay.
9. 9

   Extract broken studs if necessary
   If any exhaust manifold studs broke during removal, use a stud extractor tool or drill them out carefully. Clean the threads in the cylinder head with a thread chaser. If drilling is required, use cutting oil and work slowly to avoid damaging the cast-iron cylinder head threads. Use extreme care when drilling broken studs. Cast-iron cylinder head threads can still be damaged if drilling is off-center. Consider professional machine shop assistance if uncomfortable with extraction.
   ⚠️Use extreme care when drilling broken studs. Aluminum cylinder head threads are easily damaged. Consider professional machine shop assistance if uncomfortable with extraction.
10. 10

    Clean mounting surfaces
    Thoroughly clean all gasket material from the cylinder head surface and exhaust manifold mating surfaces using a gasket scraper and wire brush. Remove all carbon deposits. Clean the turbocharger mounting surface on the manifold as well. Wipe surfaces clean with solvent and inspect for cracks or damage. Do not gouge or scratch the cylinder head sealing surface. Use appropriate scrapers and take care not to score the cast-iron surface.
    ⚠Do not gouge or scratch the cylinder head sealing surface. Use plastic scrapers on aluminum surfaces if possible.
11. 11

    Install new studs
    Thread new exhaust manifold studs into the cylinder head by hand. Use a stud installation tool or double-nut method to tighten studs to proper depth. Ensure all studs are fully seated and uniform in height. Apply anti-seize to stud threads going into the head if specified by the stud manufacturer.
12. 12

    Install new exhaust manifold
    Position the new exhaust manifold gasket on the cylinder head studs. Carefully guide the exhaust manifold onto the studs, ensuring the gasket remains properly aligned. Install all twelve manifold nuts finger-tight. Using a torque wrench, tighten nuts in a spiral pattern from center outward in three stages: first to 1/3 final torque, then 2/3, then final torque specification per factory service manual (typically 32 ft-lbs but verify with service data).
13. 13

    Install turbocharger
    Install a new gasket on the exhaust manifold turbo mounting surface. Carefully position the turbocharger onto the manifold studs, aligning the oil drain and feed ports. Install new mounting nuts and tighten in a criss-cross pattern to factory specification (typically 24 ft-lbs but verify with service data).
14. 14

    Reconnect turbocharger oil lines
    Install new crush washers on the oil feed banjo bolt. Reconnect the oil feed line to the turbocharger and tighten the banjo bolt to specification. Install new gasket or o-ring on the oil drain tube and reconnect it to both the turbocharger and engine block. Ensure all connections are secure and properly aligned.
15. 15

    Reinstall remaining components
    Reinstall the exhaust downpipe to the turbocharger outlet and tighten the V-band clamp or flange bolts. Reconnect EGR components if equipped. Reinstall the air intake system and filter housing. Reconnect all electrical connections and vacuum lines. Reconnect battery cables (positive first, then negative).

Reassembly

1. Torque all fasteners in proper sequence and to factory specifications using a calibrated torque wrench
2. Double-check all oil line connections for tightness and proper gasket installation
3. Verify all electrical connectors are fully seated and locked
4. Ensure exhaust downpipe connection is properly sealed to prevent exhaust leaks

Verification

• Check engine oil level and top off if necessary due to oil loss from turbo lines
• Start engine and listen for exhaust leaks at manifold, turbo, and downpipe connections
• Allow engine to reach operating temperature and verify no oil leaks from turbocharger oil feed or drain lines
• Check for proper turbocharger boost response during test drive
• Inspect all connections after first heat cycle and re-torque manifold nuts if specified by manufacturer
• Verify no exhaust smell in cabin and proper exhaust flow from tailpipe
• Scan for diagnostic trouble codes related to oxygen sensor or boost pressure

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

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