CCV Delete vs CCV Filter Replacement — They’re Not the Same Thing
Before anyone can talk about whether a CCV delete is a good idea, you have to understand what the factory system actually is, because “delete” means something very specific here.
The 6.7 Cummins factory crankcase ventilation system is not a simple breather tube. It’s a closed circuit with a serviceable filter element. Crankcase pressure — the blow-by that sneaks past the piston rings on every combustion stroke — exits the valve cover into a housing mounted on top of the engine. Inside that housing is a coalescing filter, essentially a dense fiber mesh, designed to separate oil droplets from the crankcase vapor.
The cleaned vapor is then routed back into the intake tract ahead of the turbocharger. The separated oil drains back into the crankcase through a check valve. The filter is a maintenance item — Cummins recommends replacing the CCV filter every 60,000 miles under normal duty, sooner under severe service. A factory replacement filter costs $60 to $120 from a Ram dealer, and replacing it takes about 20 minutes — remove the housing cover, pull the old filter, drop in the new one.
A CCV delete is not a filter replacement. It removes the entire closed-circuit system — the filter housing, the return line to the intake, and the drain-back line — and replaces it with a fitting and a hose that vents crankcase vapor directly to atmosphere, typically routed down along the frame rail and pointed at the ground. The engine breathes clean air through the turbo inlet. The crankcase vents freely under the truck.
The difference matters because a lot of owners don’t know the factory system even has a filter. They think CCV delete means removing a simple PCV tube like on an old 12-valve, and they don’t realize there’s a serviceable part in between that can simply be maintained. Whether the delete is worth it for you depends heavily on whether you’d rather pay for a replacement filter every 60,000 miles or accept the trade-offs of venting to atmosphere.
The 4 Big Advantages of a 6.7 Cummins CCV Delete
1. Eliminates a Recurring Maintenance Cost
This is the most straightforward reason most owners do it. A CCV filter is good for roughly 60,000 miles. At a dealer price of $60 to $120 per filter, an owner who keeps the truck for 300,000 miles buys four to five filters. Add the time involved in swapping them, and the delete pays for itself the first time you skip a filter change.
If you’re running an O-ring aftermarket filter that sells for $30 to $40, the math is less compelling on pure cost — but you’re still replacing a filter four or five times over the truck’s life, and you still have the underlying issue of what happens when the filter clogs faster than expected.
2. Prevents Oil from Entering the Intake — Even When the Filter Fails
The factory CCV filter is good, but it’s not perfect. As the filter loads with oil and debris, its efficiency drops. A partially loaded filter lets progressively more oil mist through into the turbo inlet. On a truck that tows heavy or runs high boost frequently — which means more blow-by flowing through the filter — the filter saturates faster than Cummins’ 60,000-mile interval predicts.
When a CCV filter becomes fully saturated, the coalescing media can no longer separate oil from vapor. At that point, the factory system is feeding oil mist into the turbocharger at the same rate as if no filter existed. Owners who pull the intercooler boot on a 6.7 Cummins with 80,000 miles on a factory CCV filter routinely find a thick coating of oil inside — proof that the filter stopped doing its job well before the replace-by mileage.
A delete removes the filter from the equation entirely. There is no filter to saturate, no failure mode that silently feeds oil to the turbo, and no maintenance interval to track. The small amount of oil vapor that would have gone through a saturated filter is vented under the truck instead.
3. Measurably Cleaner Intake Air Temperature
Oil mist in the intake tract does two things that hurt performance. First, it coats the intercooler passages with an insulating film that reduces heat transfer efficiency. Every degree of charge air temperature increase costs roughly 0.1 percent of power, and a heavily oil-coated intercooler can add five to ten degrees to charge air temps at sustained load. Second, oil vapor entering the combustion chamber lowers the effective octane rating of the air-fuel mixture, which increases the risk of detonation under high cylinder pressure.
Neither effect is dramatic on its own, but on a tuned 6.7 Cummins making 500-plus horsepower, the cumulative impact of oil-contaminated intake air becomes meaningful. A CCV delete guarantees that every molecule of air entering the turbocharger is oil-free. The intercooler stays dry, charge air temperatures stay predictable, and the engine management system operates with the air density it’s calibrated for.
4. Extends Turbocharger Compressor Life
The factory VGT on a 6.7 Cummins is a precision piece of equipment. The compressor wheel spins at over 100,000 RPM and its blade aerodynamics are sensitive to surface contamination. Oil mist from the CCV system deposits a thin coating on the compressor blades that bakes into a hard carbon layer as the turbo heat-cycles.
Over time, this coating roughens the blade surfaces, reduces aerodynamic efficiency, and in extreme cases can create enough surface irregularity to trigger compressor surge at the transition between low and high boost. A CCV delete prevents every molecule of oil from reaching the compressor wheel, which means the turbo stays clean and runs the blade geometry it was designed with for the life of the truck.
The 3 Real Downsides and Risks
1. The Smell Will Find Its Way Into the Cab
The most immediate difference you’ll notice after a CCV delete is the odor. Instead of being burned cleanly inside the engine, hot oil vapors vent into the atmosphere under the truck. When sitting at a traffic light or idling with the windows down, these oily fumes are naturally drafted straight into the cab through your truck’s HVAC fresh air intake. It’s a scent that smells like an old tractor, and many daily-driven owners — and their spouses — find it tiresome.
Inside the cab with the windows up and the HVAC set to recirculate, the smell is undetectable. With the windows down at a stoplight, it’s there. In a drive-through, it’s noticeable. If you’re running the truck in a closed shop or garage to warm it up in winter, the smell accumulates.
Whether this is a dealbreaker is entirely personal tolerance. Some owners don’t care at all. Others notice it immediately and find it annoying. If you’re the type who keeps the interior detailed and can’t stand the smell of diesel exhaust on your clothes, factor the odor into your decision.
2. Cold Weather Ice Plug — The Rear Main Seal Killer
This is the single biggest mechanical risk of an atmospheric dump setup, and anyone who lives north of the Mason-Dixon line needs to know about it. In extreme sub-zero winter climates, the water vapor inherently mixed with your crankcase blow-by can condense and freeze inside the lower end of the vent hose. This creates a solid ice plug.
With no way to vent, crankcase pressure spikes instantly. The pressure chooses the path of least resistance — which often means violently blowing out the expensive rear main engine seal or oil pan gasket. An engine can pump itself dry of oil on the highway before the gauge even catches up.
The fix is straightforward: route the vent hose with a continuous downward slope and position the outlet where road heat and engine bay warmth keep it above freezing. Some owners in cold climates wrap the lower section of the hose with heat tape or route it alongside the exhaust to prevent ice formation. If you live where winter temperatures regularly drop below 15°F, do not skip this step.
3. Warranty and Emissions Legality
This is the dealbreaker for some owners and a non-issue for others, and you need to know which camp you’re in before buying a kit.
From a federal emissions standpoint, the CCV system is part of the engine’s emissions control design. Tampering with it — including deleting it — is technically a violation of the Clean Air Act. In practice, enforcement varies enormously by state. States with diesel emissions testing will flag a visible vent tube during inspection. States with visual-only safety inspections may never notice it. States with no diesel inspection at all will never know.
From a warranty standpoint, a CCV delete gives the dealer an opening to deny powertrain warranty claims if they determine the modification contributed to a failure. On an older 6.7 Cummins that’s long out of warranty, this is irrelevant. On a 2023 Ram still under the 5-year/100,000-mile powertrain warranty, it’s a real risk. If you’re still under warranty and can’t afford to self-insure a denied claim, replace the filter instead.
How to Decide: A Use-Case Guide
The CCV delete is not universally better than the factory system. It’s better for some owners and a sideways move for others. Here’s how the decision breaks down by how you use your truck.
Daily Driver, Light Duty — Replace the Filter
If your 6.7 Cummins spends its life commuting, hauling light loads, and rarely sees sustained high boost, the factory CCV filter is adequate. Replace it on schedule every 60,000 miles with an aftermarket filter for $30 to $40, and you’ll prevent oil accumulation in the intake without the smell or legality concerns. At light load, blow-by through the filter is low enough that an on-schedule filter change keeps the intake acceptably clean. The delete doesn’t buy you much because the intake isn’t getting heavily oiled in the first place.
Heavy Towing, High Boost — Consider the Delete
If your truck earns its living with a trailer hooked to it, the CCV filter is working harder than the maintenance interval accounts for. Sustained high boost means sustained high blow-by, which means more oil mist through the filter and faster filter saturation. In this use case, the filter stops doing its job well before the mileage interval, and the intake is almost certainly oil-contaminated at any given moment. The delete provides a real, sustained benefit — drier intake air, cleaner intercooler, and no filter to saturate prematurely.
Tuned and Deleted — Do the CCV Delete
If your 6.7 Cummins is already deleted and tuned, the CCV delete is a no-brainer. You’ve already addressed the emissions equipment that matters most for reliability, and the CCV is the easiest piece to complete the picture. More power means more blow-by, and more blow-by through a factory filter means the intake is getting more oil than it would on a stock truck. At this point the factory CCV system is the weak link in an otherwise fully freed-up engine.
Still Under Warranty — Wait
A $23 delete kit is not worth a denied warranty claim on a $10,000 engine. Replace the filter on schedule until the powertrain warranty expires, then decide. The factory CCV filter works well enough for the warranty period, and the truck will not be measurably harmed by running it for 100,000 miles before switching.
Conclusion
The 6.7 Cummins CCV delete is one of those rare modifications where the answer to “should I do it” genuinely depends on who’s asking. A daily-driven, stock-tuned, under-warranty truck benefits modestly if at all. A heavy-towing, tuned, high-mileage truck benefits meaningfully, by keeping oil out of the intercooler and off the turbo.
If you’ve decided the delete is right for your use case, the 2007.5-2018 Ram 6.7L Cummins CCV Open Breather Kit replaces the entire factory CCV system with a fitting, vent hose, and hardware for less than the cost of one dealer filter replacement. It’s a 30-minute install with hand tools, and it removes the CCV filter from your maintenance list permanently. If you live where winter temperatures dip below freezing, take the extra 10 minutes to route the hose with good slope and position the outlet where it won’t ice up — the difference between a bulletproof setup and a tow truck is a frozen hose.
If the smell or legality concerns make the delete a tougher sell, replace the CCV filter on schedule and keep the factory system. The point isn’t that one path is right and the other is wrong. The point is knowing the trade-offs so you can pick the right path for your truck and the way you use it.
Find the parts your Cummins needs at www.dieseltok.com.
FAQ
What happens if you don’t replace the CCV filter on a 6.7 Cummins?
A fully saturated CCV filter stops separating oil from crankcase vapor. Raw oil mist enters the turbocharger inlet, coats the intercooler, and eventually reaches the intake manifold. The engine runs on oil-contaminated air, which reduces intercooler efficiency, fouls the turbo compressor, and can trigger intake manifold fouling severe enough to affect idle quality over tens of thousands of miles.
Will a CCV delete cause my 6.7 Cummins to leak oil?
No. The crankcase is not pressurized differently by a CCV delete — the vent tube provides the same pressure relief the factory system does, just to a different outlet. If your Cummins develops an oil leak after a CCV delete, the leak was forming before the modification and the vent tube didn’t cause it.
How long does a 6.7 Cummins CCV filter last?
Cummins recommends replacement every 60,000 miles under normal service. Severe service — sustained towing, high-idle operation, frequent high-boost driving — can saturate the filter in as little as 40,000 to 50,000 miles. A visual inspection of the intercooler boot for oil residue is a better indicator than the mileage clock.
Does the CCV delete affect engine braking or turbo braking?
No. The exhaust brake and turbo brake operate on the exhaust side of the engine. The CCV system operates on the intake side. They are mechanically unrelated.
Can a dealership detect a CCV delete?
Yes. The factory CCV housing is prominently visible on top of the engine. If it’s replaced with a hose and fitting, any technician who opens the hood will see the modification immediately. Whether they care depends on the dealership and the warranty status.
Is the CCV delete reversible?
Completely. The factory CCV housing bolts on and off with standard hardware, and the vent hose attaches with a hose clamp and zip ties. Reverting to the factory system takes the same 30 minutes the installation took. If you’re in a state with emissions testing, the stock system can be reinstalled for inspection.
Does a CCV delete increase horsepower?
Not directly. The power gain, if any, comes from slightly lower and more stable charge air temperatures over sustained high-boost operation — perhaps 5 to 10 degrees, translating to a fraction of a percent in power. What you gain is consistency, not a dyno number. The intercooler works more efficiently with dry air, and the engine management can hold timing and fueling targets without compensating for oil-contaminated intake conditions.
What’s the difference between a CCV delete and a CCV catch can?
A CCV delete vents crankcase vapor to atmosphere, keeping oil out of the intake and intercooler permanently. A catch can routes vapor through a baffled canister, condenses the oil, and returns cleaned air to the intake. The delete is cheaper and maintenance-free, vents a small amount of oil mist under the truck, and carries a cold-weather risk: the vent hose can freeze shut in sub-zero temperatures, and a blocked hose spikes crankcase pressure fast enough to blow out a rear main seal. Route the hose properly and you solve this; ignore it in winter and you could lose an engine. The catch can costs more and requires periodic emptying, but eliminates the smell, underbody oil, and freeze risk.
