EGR Cooler

This procedure covers the removal and replacement of the EGR cooler on a 2007 Ram 3500 with the 5.9L Cummins diesel engine, including coolant system draining and refilling.

Warnings

Tools required

Parts

• EGR cooler assembly × 1 — Use OEM specification
• EGR cooler gaskets × 1 — Typically included with EGR cooler kit
• EGR valve gasket × 1 — Use OEM specification
• Coolant hose clamps × 4 — Replace as needed
• EGR intake grid heater gasket × 1 — Use OEM specification

Fluids

• HOAT coolant 50/50 — 28 qt

Preparation

1. Park vehicle on level ground and allow engine to cool completely (minimum 2 hours)
2. Disconnect both negative battery cables to prevent electrical issues
3. Place large drain pan under radiator and engine
4. Remove engine cover if equipped
5. Document all electrical connections and hose routing with photos for reference during reassembly

Procedure

1. 1

   Drain cooling system
   Open the radiator petcock at the bottom of the radiator and drain coolant into a suitable container. If a block drain is accessible on the engine block, open it as well to drain additional coolant. Allow system to drain completely.
2. 2

   Remove air intake components
   Disconnect the air intake tube from the turbocharger inlet. Remove the air filter housing assembly to gain access to the top of the engine. Disconnect the intake air temperature sensor electrical connector. Set components aside in a clean area.
3. 3

   Disconnect EGR valve and associated components
   Locate the EGR valve on the passenger side of the engine near the intake manifold. Disconnect the electrical connector from the EGR valve. Remove the bolts securing the EGR valve to the intake manifold and EGR cooler outlet. Carefully remove the EGR valve and set aside. Note the orientation of gaskets for reassembly.
4. 4

   Remove intake grid heater
   The intake grid heater is located between the intake manifold and intake horn. Disconnect the electrical connections to the grid heater. Remove the mounting bolts securing the grid heater assembly. Carefully lift the grid heater from the intake manifold, noting gasket position. Inspect for carbon buildup or damage.
5. 5

   Disconnect coolant lines from EGR cooler
   Locate the coolant supply and return lines connected to the EGR cooler on the passenger side of the engine. Use hose clamp pliers or appropriate tool to remove the hose clamps. Carefully twist and pull the coolant hoses from the EGR cooler ports. Additional coolant will drain from these lines, so have a drain pan ready. Inspect hoses for cracks or deterioration.
6. 6

   Remove exhaust connection from EGR cooler
   At the rear of the EGR cooler, locate the exhaust pipe connection coming from the exhaust manifold. Remove the bolts or V-band clamp securing the exhaust pipe to the EGR cooler inlet. You may need to apply penetrating oil to fasteners if corrosion is present. Separate the connection and move the exhaust pipe out of the way.
7. 7

   Remove EGR cooler mounting bolts
   Locate all mounting bolts securing the EGR cooler to the engine block and associated brackets. There are typically 3-4 mounting bolts. Remove these bolts completely, supporting the EGR cooler assembly to prevent it from falling. The cooler may be stuck due to gasket material or corrosion.
8. 8

   Remove EGR cooler assembly
   Carefully maneuver the EGR cooler assembly out of the engine bay. This may require twisting and angling due to tight clearances around the turbocharger and other components. Once removed, inspect the cooler for external damage, cracks, or signs of internal failure such as coolant residue in the exhaust ports.
9. 9

   Clean all mounting surfaces
   Using a gasket scraper and wire brush, thoroughly clean all gasket mating surfaces on the intake manifold, exhaust connection point, and engine block mounting locations. Remove all old gasket material, carbon deposits, and debris. Finish by wiping surfaces with brake cleaner and a clean rag. Surfaces must be completely clean and flat for proper sealing.
10. 10

    Inspect and prepare new EGR cooler
    Unbox the new EGR cooler and verify it matches the old unit. Check that all gaskets are included in the kit. Install new gaskets on the EGR cooler in their proper positions, ensuring they are seated correctly. Do not use gasket sealant unless specifically required by manufacturer instructions.
11. 11

    Install new EGR cooler assembly
    Carefully maneuver the new EGR cooler into position, reversing the removal process. Align the mounting holes with the engine block and brackets. Start all mounting bolts by hand to ensure proper threading. Tighten mounting bolts in a cross pattern to ensure even seating. Torque mounting bolts to the manufacturer-specified value (verify OEM spec; do not over-torque to avoid cracking the cooler housing).
12. 12

    Reconnect exhaust connection
    Position the exhaust pipe to the inlet of the new EGR cooler. Install a new gasket if one was included or if the old one is damaged. Install the mounting bolts or V-band clamp and tighten securely. Ensure the connection is properly aligned to prevent exhaust leaks.
13. 13

    Reconnect coolant lines
    Slide the coolant hoses onto the EGR cooler ports, ensuring they are fully seated. Install new hose clamps and position them properly on the hose, not over the port edge. Tighten clamps securely but avoid over-tightening which can damage the hoses or cooler ports.
14. 14

    Reinstall intake grid heater and EGR valve
    Install a new gasket on the intake manifold surface. Position the intake grid heater and install mounting bolts, tightening in a cross pattern. Reconnect electrical connections to the grid heater. Install a new gasket on the EGR valve mounting surface. Position the EGR valve and install mounting bolts, ensuring proper alignment. Reconnect the EGR valve electrical connector.
15. 15

    Refill cooling system
    Close the radiator petcock and any block drains that were opened. Fill the cooling system with fresh HOAT 50/50 coolant mixture through the coolant expansion/degas bottle. Fill slowly to minimize air pockets. A vacuum refill tool is recommended to eliminate air from the system. Fill to the proper level as indicated on the overflow reservoir. Run the engine until the thermostat opens, adding coolant to the expansion bottle as needed. Once at operating temperature and coolant level is stable, install the reservoir cap and check for leaks.

Reassembly

1. Reinstall the air filter housing and intake tube, ensuring all clamps are tight and the IAT sensor is reconnected
2. Reinstall the engine cover if equipped
3. Reconnect both negative battery cables
4. Double-check that all electrical connectors, coolant hoses, and mounting bolts have been properly installed
5. Verify no tools or parts have been left in the engine bay

Verification

• Start the engine and allow it to reach operating temperature while monitoring for coolant leaks around the EGR cooler connections
• Check for exhaust leaks at the EGR cooler exhaust connection by listening for hissing sounds
• Verify the coolant level remains stable in the overflow reservoir after the engine reaches operating temperature
• Check for proper EGR valve operation by monitoring for check engine lights and scanning for EGR-related fault codes
• Monitor exhaust smoke color during initial operation - white smoke may indicate coolant contamination if the job was not completed properly
• Road test the vehicle and verify normal operation with no overheating or unusual performance issues
• Recheck coolant level after the first drive cycle and top off if necessary, as trapped air may have purged from the system

Related trouble codes on this vehicle

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