Home » 2004-2005 6.6L Chevy GMC Silverado LLY Duramax Diesel EGR Delete Kit

Compatibility: 2004–2005 Chevrolet Silverado / GMC Sierra 6.6L LLY Duramax

Product: Full 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 & INITIAL DISASSEMBLY

Step 1: Electrical & Fluid Management

  1. Safety: Disconnect the negative cables from both batteries to isolate the electrical system.

  2. Coolant Drain: Drain the engine coolant into a clean catch bucket via the radiator drain plug.

Step 2: Intake Component Removal

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

  2. Intake Piping: Loosen the primary hose clamps on the air induction pipe and remove it from the engine bay.

PHASE 2: INTAKE MANIFOLD & HARNESS ISOLATION

Step 3: Harness & Intake Bridge

  1. Harness Isolation: Remove the cable ties securing the wiring harness to the intake bridge. Carefully pull the harness away from the manifold to clear the workspace.

  2. Manifold Extraction: Remove the four (4) bolts securing the intake bridge to the EGR valve and the two (2) bolts connecting it to the crossover pipe.

  3. Boost Connection: Loosen the hose clamp on the intercooler (boost) pipe to fully extract the intake bridge assembly.

Step 4: PCV System Disconnect the PCV (Positive Crankcase Ventilation) hose from the passenger side of the engine.

PHASE 3: EGR SYSTEM EXTRACTION

Step 5: Full Assembly Removal

  1. Remove the four (4) bolts/nuts from the exhaust side of the EGR cooler.

  2. Remove the four (4) bolts/nuts securing the EGR valve assembly to the engine.

  3. Disconnect the coolant hoses at both ends of the cooler.

  4. Lift the entire EGR assembly (Valve and Cooler) vertically out of the engine bay.

PHASE 4: INSTALLATION & COOLANT BYPASS

Step 6: High-Flow Intake Installation Install the new performance intake bridge onto the engine. Ensure all mounting surfaces are clean to maintain a proper boost seal.

Step 7: Exhaust Block-Off Install the Polished Stainless Steel Exhaust Plug using the provided hardware (two 20mm and two 30mm bolts). Ensure the plate is seated flush against the manifold.

Step 8: Coolant Circuit Integration Install the provided performance bypass hose. This connects the coolant flow from the firewall (heater core return) to the front of the engine, effectively bypassing the circuit previously occupied by the EGR cooler.

PHASE 5: REASSEMBLY & FINAL TESTING

Step 9: System Restoration

  1. Reinstall the PCV hose, wiring harness (securing with new cable ties), and the intercooler boost pipe in the reverse order of disassembly.

  2. Reinstall the intake induction piping and resonator.

Step 10: Commissioning & Quality Control

  1. Refill the cooling system with a 50/50 mix of approved Dex-Cool (or equivalent) coolant.

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

  3. Audit: Inspect the exhaust block-off plate and new coolant lines for any signs of leaks. Top off the coolant reservoir once the 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.