Description
Product Overview
The iFJF Duramax LMM EGR Delete Kit is a comprehensive engine preservation solution for 2007.5–2010 Chevrolet Silverado and GMC Sierra HD trucks equipped with the 6.6L LMM Duramax turbo diesel. This complete kit addresses the single most problematic emissions system on the LMM platform — the exhaust gas recirculation system — which is widely recognized by diesel technicians and Duramax enthusiasts as a leading cause of reduced engine longevity, decreased fuel economy, and expensive component failures.
On the LMM Duramax, the EGR system routes soot-laden exhaust gas through an EGR cooler (a heat exchanger prone to internal cracking), then into the intake tract via the EGR valve. When the EGR cooler fails — and they do fail, often catastrophically — coolant enters the intake stream, leading to hydrolock risk, head gasket failure, and turbocharger damage. Even when functioning "correctly," the system coats the intake manifold, intake valves, and swirl flaps with a thick layer of carbon-coke that progressively restricts airflow and degrades performance.
Our kit provides everything needed for a complete EGR system removal: a CNC billet EGR valve delete block off plate, a billet EGR cooler delete bridge, and a high-flow passenger-side up-pipe that replaces the factory pipe's EGR takeoff port. Every component is precision-machined from 6061-T6 billet aluminum or mandrel-bent from 304 stainless steel, designed to withstand the extreme heat, pressure, and vibration cycles unique to the 6.6L Duramax platform.
Key Features
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Complete Three-Component Kit — Unlike partial kits that only delete the EGR valve, the iFJF LMM kit includes: (1) CNC billet EGR valve block off plate, (2) billet aluminum EGR cooler delete bridge, and (3) 304 stainless steel passenger-side up-pipe without EGR takeoff. This is the full system — everything you need in one box.
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EGR Cooler Delete Bridge — The LMM's EGR cooler is the most failure-prone component in the system. Our billet aluminum delete bridge replaces the cooler entirely, eliminating the risk of internal coolant leaks into the intake. The bridge routes coolant directly to the factory return path, maintaining proper cooling system function without the EGR cooler in the circuit.
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304 Stainless Steel Up-Pipe — The passenger-side up-pipe replaces the factory pipe that routes exhaust from the exhaust manifold to the turbocharger. By eliminating the EGR takeoff port, this pipe delivers unrestricted exhaust flow to the turbine — reducing backpressure and improving turbo spool characteristics compared to the restricted factory pipe.
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6061-T6 Billet Aluminum Construction — Both the valve block off plate and cooler delete bridge are CNC machined from solid 6061-T6 billet aluminum bar stock. No castings, no stampings — just precise, warp-resistant components that maintain seal integrity under the extreme thermal cycling of a 6.6L turbo diesel.
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Complete Hardware & Gasket Kit — Includes all required stainless steel bolts, washers, exhaust gaskets, O-rings, and coolant hose fittings for a proper, leak-free installation. No trips to the parts store mid-install.
Compatibility
| Year Range |
Make |
Model |
Engine |
Notes |
| 2007.5–2010 |
Chevrolet |
Silverado 2500HD |
6.6L Duramax LMM (LLY-based) |
All cab configurations |
| 2007.5–2010 |
Chevrolet |
Silverado 3500HD |
6.6L Duramax LMM |
SRW & DRW |
| 2007.5–2010 |
GMC |
Sierra 2500HD |
6.6L Duramax LMM |
All cab configurations |
| 2007.5–2010 |
GMC |
Sierra 3500HD |
6.6L Duramax LMM |
SRW & DRW |
Important fitment notes:
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2007.5 model year only — This kit fits the "Classic" body style transition trucks produced from mid-2007 onward. It is not compatible with 2001–2007 LB7/LLY/LBZ Duramax engines, which use a different EGR and up-pipe configuration.
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Not compatible with 2011+ LML Duramax — The LML (2011–2016) uses a different EGR and exhaust architecture. This kit is specific to the LMM engine code.
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Cab-and-chassis models — Verify up-pipe clearance on cab-and-chassis configurations; fitment confirmed for standard pickup bed configurations.
Specifications
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EGR Valve Block Off Plate: 6061-T6 billet aluminum, CNC machined, 6.35 mm (1/4") thickness
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EGR Cooler Delete Bridge: 6061-T6 billet aluminum, CNC machined with integrated coolant passage
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Passenger Up-Pipe: 304 stainless steel, mandrel-bent, TIG-welded flanges, 2.5" OD tubing
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Up-Pipe Flanges: Laser-cut 304 stainless steel, 3/8" thickness, TIG-welded with back-purged welds
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Hardware: Grade 304 and 316 stainless steel bolts, nuts, and washers (application-specific)
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Gaskets & Seals: Multi-layer stainless steel (MLS) exhaust gaskets, Viton O-rings for coolant fittings
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Surface Finish: Block off plate and bridge — CNC natural finish; up-pipe — brushed stainless
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Package Weight: Approximately 3.6 kg (8.0 lbs)
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Package Contents: 1× EGR valve block off plate, 1× EGR cooler delete bridge, 1× 304SS passenger up-pipe, MLS exhaust gaskets (×4), Viton O-rings (×2), stainless hardware kit, coolant hose fittings, installation guide
Installation Notes
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Disconnect both batteries — Duramax HD trucks have dual batteries. Disconnect negative terminals on both before starting any work near the starter, alternator, or engine harness.
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Drain coolant — Drain approximately 2–3 gallons from the radiator petcock. The EGR cooler is part of the engine coolant circuit, and you will lose coolant when removing the cooler.
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Remove the factory EGR cooler — The LMM EGR cooler is located on the passenger side of the engine, mounted between the exhaust up-pipe and the intake manifold. Disconnect the coolant lines (mark their routing), unbolt the cooler from its bracket, and remove it.
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Remove the factory up-pipe — The passenger-side up-pipe connects the exhaust manifold to the turbocharger. The factory pipe incorporates the EGR cooler feed port. Remove the turbo heat shield, unbolt the up-pipe from the manifold and turbo flanges, and extract the pipe. This is often the most time-consuming step — expect to work in tight quarters.
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Install the iFJF up-pipe — Position the 304SS up-pipe, install new MLS gaskets at both the manifold and turbo flanges, and torque bolts to factory specification (typically 30–35 ft-lbs). The TIG-welded flanges ensure perfect alignment.
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Install the cooler delete bridge — Connect the coolant lines to the delete bridge using the supplied fittings and Viton O-rings. The bridge maintains proper coolant flow routing while eliminating the cooler from the circuit.
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Install the valve block off plate — Remove the EGR valve from the intake manifold, install the block off plate with the supplied gasket, and torque to specification.
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Refill coolant and bleed the system — Refill with the correct Dex-Cool compatible coolant, perform the bleed procedure (elevate front of vehicle, run engine with heater on full), and check for leaks at all connections.
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ECU tuning required — The LMM ECM will detect the missing EGR system components and trigger diagnostic trouble codes, potentially entering reduced-power (limp) mode. A custom ECM tune is required to disable EGR-related DTCs and restore full engine functionality.
Tools needed: Standard and deep metric socket sets (8 mm–15 mm), torque wrench, coolant drain pan, penetrating oil, hose clamp pliers, turbo heat shield tools, floor jack and stands for under-vehicle access. Estimated time: 4–6 hours for an experienced DIY mechanic; 3–4 hours for a professional diesel technician.
Frequently Asked Questions
Why should I delete the EGR on my LMM Duramax?
The LMM EGR system is the leading cause of several expensive failure modes on the 6.6L Duramax. The EGR cooler is known to crack internally, introducing coolant into the intake — a condition that can hydrolock the engine and bend connecting rods. Even a properly functioning EGR system continuously coats the intake manifold, intake valves, and turbo compressor wheel with abrasive carbon-coke, progressively reducing airflow and degrading fuel economy. Deleting the EGR system eliminates both failure risks and is one of the most recommended reliability modifications in the Duramax community.
Does this kit include the up-pipe?
Yes — this is a complete kit that includes the 304 stainless steel passenger-side up-pipe. Many competitors sell the up-pipe separately or omit it entirely, leaving you to source one elsewhere. The iFJF up-pipe is mandrel-bent from thick-wall 304SS and features laser-cut, TIG-welded flanges for perfect fitment.
Will this kit cause my truck to go into limp mode?
If installed without a supporting ECM tune — yes. The LMM ECM actively monitors the EGR system, and when it detects missing or non-functional EGR components, it will trigger DTCs and may engage reduced-power (limp) mode as a protective measure. A custom tune from a reputable Duramax tuner (using EFILive, HP Tuners, or similar) is mandatory. The tune must disable EGR-related DTCs, set EGR readiness monitors appropriately, and optionally optimize fuel and boost mapping for the improved airflow you'll achieve post-delete.
Is this kit compatible with my 2008 GMC Sierra 2500HD?
Absolutely. The 2008 GMC Sierra 2500HD with the 6.6L LMM Duramax is a direct-fit application. Both Chevrolet Silverado and GMC Sierra HD trucks from 2007.5–2010 share identical LMM engine architecture, EGR system layout, and exhaust configuration.
What's the difference between LMM and LBZ EGR delete kits?
The LMM and LBZ use different EGR cooler designs, different up-pipe configurations, and different ECM architectures. The LMM introduced a more complex EGR cooler with additional coolant passages and a revised up-pipe design compared to the LBZ. Components are not interchangeable between the two engine codes. This kit is specifically engineered for the LMM (2007.5–2010) platform.
Will deleting the EGR improve my fuel economy?
Many Duramax owners report a measurable improvement in fuel economy after EGR deletion — typically 1–3 MPG depending on driving conditions. The improvement comes from two sources: (1) the engine is no longer ingesting hot, oxygen-depleted exhaust gas during cruise, which improves combustion efficiency, and (2) the intake system stays clean over time, preventing the gradual airflow restriction that robs efficiency as carbon builds up. Combined with a well-calibrated tune, fuel economy gains can be significant on highway-driven trucks.
Will this kit affect the reliability of my truck?
When properly installed with a quality supporting tune, EGR deletion improves long-term engine reliability by eliminating the risk of EGR cooler failure (the #1 cause of catastrophic Duramax engine damage on LMM platforms) and preventing carbon-coke buildup in the intake system. The iFJF components are manufactured from materials selected for durability under diesel operating conditions: 6061-T6 billet aluminum for thermal stability, 304 stainless steel for corrosion resistance, and Viton seals for coolant circuit integrity at sustained high temperatures.
⚠️ Off-Road / Competition Use Only
This Duramax LMM EGR delete kit is sold exclusively for off-road, racing, and competition use. The Clean Air Act (42 U.S.C. §7522(a)(3)) expressly prohibits tampering with or removing emissions control devices on motor vehicles. Installation of this product on a vehicle operated on public roads is a violation of federal law and may result in penalties of up to $4,819 per violation. Additionally, state and local regulations may impose further restrictions. This product is not CARB-certified and is not legal for sale or use in California on pollution-controlled motor vehicles. The purchaser and installer assume all liability for compliance with applicable laws. iFJF is not responsible for improper use, installation, or any consequences thereof.
