Home » 2004.5-2005 6.6L Chevy GMC Duramax LLY Diesel EGR Delete Kit

Compatibility: 2004.5–2005 Chevrolet Silverado / GMC Sierra 6.6L LLY Duramax

Product: Complete EGR Valve & Cooler Delete Performance Kit

LEGAL DISCLAIMER & COMPLIANCE

OFF-ROAD USE ONLY: This high-performance racing component is engineered exclusively for competition or sanctioned off-road use. It does not comply with federal or local emissions laws for highway operation. Installation on any vehicle registered for public roads is strictly prohibited. The end-user assumes all legal liability and risk associated with the installation and use of this product.

PHASE 1: PREPARATION & INDUCTION REMOVAL

Step 1: Electrical & Fluid Management

  1. Safety: Disconnect the negative cables from both batteries to prevent electrical shorts.

  2. System Drain: Drain the engine coolant into a clean catch bucket via the radiator drain plug or lower radiator hose.

  3. Resonator: Loosen the mounting bolt and hose clamp to remove the top-mounted intake resonator.

Step 2: Air Intake Extraction

  1. Disconnect the Mass Air Flow (MAF) sensor harness.

  2. Loosen the primary hose clamps and remove the intake tube from the engine bay.

  3. Remove the wire loom fasteners (zip-ties) and unplug the wiring harness from the intake pipe to clear the workspace.

Step 3: Intake Bridge & PCV Disconnection

  1. Remove the intake bridge assembly, which is secured by one (1) hose clamp and six (6) mounting bolts.

    • CRITICAL: Immediately cover the open intake ports with clean shop rags to prevent debris from entering the turbocharger or engine.

  2. Disconnect the PCV (Positive Crankcase Ventilation) hose from the passenger side of the engine.

PHASE 2: EGR SYSTEM EXTRACTION

Step 4: Full Assembly Removal

  1. Remove the four (4) bolts and nuts securing the EGR valve to the engine.

  2. Disconnect all coolant lines leading to the EGR cooler unit.

  3. Extract the entire EGR valve and cooler assembly from the vehicle.

    • Note: Retain the factory exhaust gasket; it is required for the installation of the new block-off plate.

PHASE 3: COMPONENT INSTALLATION & BYPASS

Step 5: High-Flow Intake Bridge Prep Pre-assemble the new intake bridge using the provided O-ring sealed baffle.

  • Tech Tip: Ensure the two (2) longer bolts are utilized on the front-facing side of the pipe for correct alignment and structural integrity.

Step 6: Bracket & Exhaust Block-Off

  1. Support Bracket: Install the provided support bracket onto the engine using a factory bolt and the supplied M10 x 20mm hex head bolt.

  2. Exhaust Block-Off: Install the exhaust block-off plate using the provided 20mm and 30mm bolts.

    • Note: Hardware must be installed from the rear of the baffle plate for a flush, high-pressure seal.

Step 7: Coolant Circuit Integration Replace the factory EGR coolant lines with the provided performance bypass hose. This connects the coolant flow directly from the return pipe to the thermostat housing, eliminating the cooler circuit.

PHASE 4: REASSEMBLY & FINAL TESTING

Step 8: System Restoration

  1. Reinstall the intake bridge, ensuring the front long bolts pass through the newly installed support bracket.

  2. Reverse the initial disassembly steps to reinstall the PCV hose, electrical harnesses, primary intake tube, and resonator.

Step 9: Commissioning & Quality Control

  1. Refill the cooling system with a 50/50 mix of approved OAT coolant.

  2. Start the engine and allow it to reach operating temperature.

  3. Inspection: Check all block-off plates and coolant connections for leaks.

  4. Final Step: Re-verify coolant levels after a short test drive to ensure all air has been purged from the system.

💡 POST-INSTALLATION ADVISORY

  • ECM Tuning: This hardware modification requires a compatible Race Tune to disable EGR logic and prevent Check Engine Lights (CEL) or "Limp Mode."

  • Maintenance: Re-torque the exhaust block-off hardware after the first 100 miles to account for thermal expansion cycles.