Why 6.7 Cummins Owners Choose a Delete Kit
The 6.7L ISB: Powerful, but Emissions-Choked
Dodge Ram and Ram trucks equipped with the 6.7L ISB Cummins have earned a serious reputation in the diesel world. From the 2007.5 introduction through today's high-output variants, the 6.7 is one of the most capable half-ton and three-quarter-ton diesel platforms ever built. But Cummins engineers didn't design the ISB in a vacuum — they had to package it with emissions hardware that satisfies EPA and CARB mandates, and that hardware comes with a price.
The DPF (Diesel Particulate Filter), EGR (Exhaust Gas Recirculation) system, and post-2013 DEF/SCR (Diesel Exhaust Fluid / Selective Catalytic Reduction) system all add heat, backpressure, and complexity that work directly against the engine's natural efficiency. The result is a truck that leaves a lot of power and fuel economy on the table from the factory — and one that becomes increasingly expensive to own once the emissions components start degrading.
DPF, EGR, and DEF Failure Patterns on 6.7 Cummins
These aren't rare edge-case failures. EGR coolers on the 6.7 are known to crack under the repeated thermal cycling of hard tow loads, introducing coolant into the intake and creating serious engine damage risk. DPF filters require active regeneration cycles that dump raw fuel into the exhaust — every regen cycle burns fuel you paid for and accelerates oil dilution. DEF quality sensors and SCR catalyst failures on 2013+ trucks can derate the engine to a crawl if left unresolved, which is a nightmare if it happens while towing.
Off-road truck owners, work truck operators, and competition diesel builders all reach the same conclusion: the most cost-effective long-term fix is a complete delete.
6.7 Cummins Emission System Overview
EGR + DPF + SCR/DEF: How They Interact
The 6.7 Cummins emissions stack is a layered system:
- EGR: Recirculates a portion of exhaust gas back into the intake to lower combustion temperatures and reduce NOx.
- DPF: Catches soot particulates downstream of the turbo.
- SCR (2013+): Injects DEF fluid into the exhaust stream before the SCR catalyst to further reduce NOx.
Each of these systems creates backpressure, introduces heat soak into the intake charge, or reduces fuel combustion efficiency. They also interact: a partially clogged DPF forces more aggressive regen cycles, which accelerates EGR cooler wear. A failing EGR dumps oily residue into the intake manifold and intercooler over time.
Year-by-Year: 2007–2012 vs. 2013–2024
- 2007.5–2012 Ram 2500/3500 Cummins: EGR + DPF equipped. No DEF system. Simpler delete — you're working with an EGR block-off plate, EGR cooler bypass, and a DPF delete pipe.
- 2013–2024 Ram 2500/3500 Cummins: Full EGR + DPF + DEF/SCR stack. Requires a DEF delete module or SCR emulator in addition to the physical pipe and plate work. The tune also needs to disable the DEF system logic in the ECM.
Knowing your year matters before you buy. A kit built for a 2010 won't include the DEF components a 2016 needs.
What's Included in a Complete 6.7 Cummins Delete Kit
A full kit for the 6.7 Cummins typically includes four core components. Here's what each one does and why it matters.
DPF Delete Pipe (4" Recommended)
The DPF is replaced with a straight-pipe section — usually 4 inches in diameter for optimal flow on the 6.7. Stepping up to 4" from the factory DPF section measurably reduces exhaust backpressure and lowers EGTs under load. The pipe is typically mandrel-bent aluminized or stainless steel with matching inlet and outlet flanges.
EGR Block-Off Plates + Cooler Bypass
EGR block-off plates seal the intake and exhaust ports where EGR gases enter. The EGR cooler bypass reroutes coolant flow so the cooler is no longer part of the loop — eliminating the failure point without leaving a dead-end coolant passage. This is one of the most important pieces of the kit; a properly executed EGR delete cleans up intake air quality and removes the primary source of intake carbon buildup on high-mileage Cummins engines.
DEF/SCR Delete Module (2013+ Trucks)
On 2013 and newer Rams, the ECM monitors the DEF fluid level, quality, and dosing pump function. If the system is physically removed without addressing the ECM logic, the truck will derate. A DEF delete module — sometimes called an SCR emulator — feeds the ECM the signals it expects while the physical DEF system is bypassed. This works in conjunction with the delete tune to fully disable DEF-related fault codes.
Pre-Loaded Cummins Delete Tuner
No delete is complete without a tuner. The ECM needs to be reflashed to remove DPF regeneration logic, disable EGR commands, turn off DEF dosing, and recalibrate fueling and boost targets to suit the now-open exhaust. Most complete 6.7 Cummins delete kits include a pre-loaded EFI Live or similar tuner with Cummins-specific calibrations. Some kits offer economy, tow, and performance tune options on the same device.
Choosing the Right Kit by Year
2007–2012: EGR + DPF Only
If you're running a pre-2013 Ram Cummins, your delete kit needs:
- EGR block-off plates and cooler bypass hardware
- 4" DPF delete pipe
- ECM tune disabling DPF regen and EGR commands
No DEF components required. This is the simpler, lower-cost path — and the tune is also less complex since there's no SCR logic to address.
2013–2024: Full EGR + DPF + DEF
2013 and newer trucks need the complete stack. Look for kits that explicitly list DEF/SCR delete compatibility for your model year. The 2019+ trucks with the high-output 6.7 (400+ HP factory) have slight ECM differences — confirm your kit vendor supports your specific year before purchasing.
For a curated selection organized by application, the diesel delete collection and diesel all-in-one kits collection at EngineGo have year-specific fitment options across both generation ranges.
Installation Overview
Difficulty and Time Estimate
A full 6.7 Cummins delete is a solid weekend job for a competent DIY mechanic with basic fabrication skills and a lift. Budget 6–10 hours for the physical work if you haven't done it before, including EGR removal, pipe fitment, and coolant line rerouting. The tune flash itself takes under an hour once the physical work is done.
EGR Removal on Cummins vs. Powerstroke
Compared to the 6.4 or 6.7 Powerstroke, EGR removal on the 6.7 Cummins is more accessible. The EGR cooler and valve are located on the driver's side of the engine and don't require the same level of cab or firewall clearance work that some Ford applications demand. The cooler-to-block coolant connections are the most labor-intensive part — plan for coolant drainage and a thorough flush after reassembly.
Tune Flash Process
Most pre-loaded tuners walk you through the flash via an OBDII connection. The process involves reading the stock ECM file, applying the delete calibration, and writing the new tune back to the ECM. Some tuners support in-cab switching between multiple tunes (economy, tow, street performance) without returning to a laptop.
Performance Gains
HP and Torque Improvement
Real-world dyno results from deleted 6.7 Cummins trucks consistently show 30–60 HP and 60–100 lb-ft torque gains depending on tune aggressiveness and supporting mods. Even a conservative economy tune typically puts 25–35 HP back over stock because the engine no longer has to fight exhaust backpressure from a loaded DPF.
EGT Reduction Under Tow Load
This is the gain towing operators care most about. With the DPF and EGR removed, exhaust flow is unrestricted and the intake charge runs cooler. EGTs under hard towing loads typically drop 100–200°F compared to stock. That margin directly translates to long-term engine longevity when you're pulling heavy loads in summer heat.
Fuel Economy Changes
Most owners report 2–4 MPG improvement after a delete and retune, particularly on highway driving. The elimination of forced DPF regen cycles (which inject raw fuel into the exhaust to burn soot) removes one of the biggest hidden fuel consumers in the stock emissions system.
Shop 6.7 Cummins Delete Kits
Ready to pull the trigger? EngineGo carries complete application-specific kits for the full 6.7 Cummins generation range.
FAQs
Will a 6.7 Cummins delete void my warranty?
Yes. Any emissions-related delete will void your powertrain warranty on a new or CPO vehicle. Most buyers doing a delete are out of factory warranty coverage already.
Do I need a tuner if I'm only deleting the EGR?
Yes. Without a tune, the ECM will continue commanding EGR operation and generate fault codes. A tune is required for any partial or full delete to function correctly.
Can I do a delete on a 2022+ Ram with the new ECM?
Later-model Cummins ECMs have tighter security protocols. Confirm with your kit supplier that their tuner has write capability for your specific ECM hardware revision before purchasing.
What's the difference between a DPF delete and a full delete kit?
A DPF-only delete removes the particulate filter and replaces the regen logic in the tune. A full delete additionally addresses EGR (and DEF on 2013+ trucks). For the best results and fewest follow-on issues, a complete kit is the recommended approach.
Is a 4" exhaust required for a Cummins delete?
Not strictly required, but 4" is the recommended diameter for the 6.7 to fully capitalize on the backpressure reduction. A 3.5" pipe will still improve flow over a stock DPF section, but 4" is the common standard for this platform.
