Last updated: September 10, 2026.
People searching "EGR delete vs DEF delete" are usually trying to distinguish two modifications that are often lumped together even though they affect different systems, carry different legal risks, and may not both apply to the same truck. Before ordering parts, identify what the EGR and DEF/SCR systems do, which Ram 6.7L Cummins model years and configurations use DEF/SCR, and how to distinguish a confirmed EGR cooler failure from similar symptoms.
Know Your Year Before You Read Any Further
This matters more than most guides mention: 2007.5-2012 Ram 6.7 Cummins pickups have EGR and a DPF, but not the DEF/SCR system — that was introduced starting with the 2013 model year. If your truck is a 2012 or earlier, the "EGR delete vs DEF delete" question doesn't really apply to you the same way, since there's no DEF system to weigh in the first place. On 2013+ trucks, you're dealing with EGR, DPF, and DEF/SCR as three separate systems that can each be addressed independently.
What an EGR Delete Kit Actually Includes
Kit contents vary by SKU and model year, but a 6.7 Cummins EGR delete generally replaces the factory EGR cooler and throttle valve with block-off plates sized to seal the mounting points, along with the gaskets and hardware for a leak-free install. The goal is stopping recirculated exhaust gas from reaching the intake entirely, not rerouting it somewhere else. A 6.7L Cummins EGR delete kit does not contain the same parts for every model year; verify the SKU's fitment and box contents before disassembly.
Why Guys Actually Look at This
The EGR cooler on the 6.7 Cummins is a well-known weak point, and a sweet smell from the tailpipe combined with coolant you keep topping off with no puddle underneath puts a cracked cooler high on the suspect list — but that combination doesn't confirm it on its own. Pressure-test the cooling system and isolate the 6.7L Cummins EGR cooler before condemning it, because hose connections, the water pump, or a head gasket can also cause coolant loss. Separately, soot from recirculated exhaust gas can cake onto the throttle valve and intake horn until it restricts airflow, which is a different failure chain from a coolant leak entirely. SPELAB's EGR cooler symptoms and diagnosis guide details the confirmation steps.
EGR Delete vs. DEF Delete — Not the Same Modification
EGR deletion and DEF/SCR deletion are often lumped together, but they are separate modifications. An EGR delete removes the exhaust gas recirculation loop. "DEF delete" is a looser term in the aftermarket — it can mean anything from software disabling DEF dosing and inducement warnings to physically removing the DEF tank, pump, and injector, up to removing the SCR catalyst itself. Any DEF/SCR modification that bypasses or disables certified NOx-control hardware falls under the same federal tampering and defeat-device framework as disabling EGR. Treat EGR deletion and DEF/SCR deletion as separate decisions with different mechanical and legal risks, not as a package deal.
Where This Actually Sits Legally
The EGR and DEF/SCR systems are both federally required emissions controls on the trucks that have them, and physically removing or disabling either one is a clear-cut case under the Clean Air Act's prohibition on tampering with or rendering inoperative a required emissions control device. The federal Clean Air Act prohibition on emissions-control tampering applies whether or not a state operates a vehicle emissions-inspection program; the absence of regular state smog checks does not make the modification legal. California Air Resources Board requirements add state enforcement and testing rules to the federal baseline; an "off-road" or "race use only" label does not by itself create a legal exemption. The EPA's enforcement initiative on aftermarket defeat devices identifies EGR and SCR as emissions-control systems covered by Clean Air Act tampering and defeat-device prohibitions, regardless of engine platform.
What Removing It Actually Involves
On the 6.7 Cummins, the job centers on disconnecting the battery, removing the intake components and lines in the way, then pulling the factory EGR cooler and valve assembly and installing block-off plates with fresh gaskets in their place. Removal steps and access points differ among 2007.5-2012, 2013-2018, and 2019+ Ram 6.7L Cummins trucks; use the instructions for the exact kit and model year. Removing or disabling the EGR system can trigger diagnostic trouble codes, warning lights, reduced-power strategies, or readiness-monitor failures when the ECU no longer receives expected EGR feedback; required calibration work depends on the model year, control strategy, and exact hardware change.
Check Fitment Before You Order
If you're looking at a combined kit that bundles EGR, DPF, and CCV work together, check the fine print — SPELAB's all-in-one kit for 2013-2018 trucks specifically excludes Cab & Chassis models and trucks with air-ride suspension, and the included tuner only supports certain PCM part numbers. Cab & Chassis configurations require a dedicated kit, not the standard pickup bundle. A 2013-2018 year range on an EGR delete kit does not prove fitment for every Ram 6.7L Cummins pickup, Cab & Chassis, air-suspension, or PCM configuration produced during those years.
Real-World Considerations
Low-load operation can command more EGR flow than sustained high-load operation, but actual EGR duty varies with engine load, coolant temperature, calibration, and model year. Sustained towing runs the engine hotter for longer and adds to overall heat exposure, which is a different kind of stress on the same components rather than more EGR flow specifically. Diagnostic codes, coolant loss, measured restriction, or other repeatable symptoms justify diagnosis; towing frequency or idle hours alone do not prove an EGR or DEF/SCR fault.
For the parts themselves, SPELAB's EGR plate cooler and throttle valve delete kit covers the core components for 2013-2018 standard pickups, and the full Cummins EGR delete kit collection covers fitment across other Ram model years and configurations if this specific kit doesn't match your truck.
FAQ
Q: What's actually included in a 6.7 Cummins EGR delete kit?
A: A typical 6.7L Cummins EGR delete kit may include block-off plates for the factory EGR cooler and throttle-valve mounting points, plus application-specific gaskets and hardware; confirm the exact SKU and box contents before installation.
Q: Is EGR delete the same as DEF delete?
A: No. An EGR delete disables or removes exhaust gas recirculation, while a DEF delete can mean disabling DEF dosing, removing DEF hardware, or removing SCR components. Both changes can fall under federal emissions-control tampering and defeat-device prohibitions.
Q: Does my truck even have a DEF system?
A: Ram 2500/3500 pickups with the 6.7L Cummins added DEF/SCR for the 2013 model year, while some earlier Ram chassis-cab applications already used DEF. Verify the model year and pickup-versus-chassis-cab configuration before diagnosing or ordering parts.
Q: Is deleting the EGR on a 6.7 Cummins legal for street use?
A: Physically removing the EGR system is a clear case of tampering with a required emissions control under the federal Clean Air Act, regardless of whether your state runs emissions inspections. An off-road or race-use label is a manufacturer disclaimer, not a legal exemption.
Q: Do I need to delete the DPF if I delete the EGR?
A: Not automatically. The two systems do different jobs, and removing one doesn't require removing the other. Mixing a deleted and a stock system can make soot-load modeling and regeneration behave unpredictably, so a compliant, matched configuration is generally more reliable than assuming both need to go.
Q: How do I know if my EGR cooler is actually failing versus something else?
A: A sweet exhaust odor and unexplained coolant loss can make the EGR cooler a suspect, but those symptoms do not confirm a failed cooler. Pressure-test the cooling system and isolate the cooler because a head-gasket leak or loose hose connection can produce a similar complaint.
About the Author
John Lee has spent 15 years turning wrenches on diesel pickups, from daily-driven tow rigs to dedicated jobsite trucks. He diagnoses emissions systems and evaluates reliability upgrades for Power Stroke, Cummins, and Duramax diesel pickups, with a focus on durability under towing, cold-weather operation, and high-idle jobsite use.
