Alright folks, let's talk about something less glamorous than a new turbo or a shiny tune, but arguably MORE critical for the long-term health and happiness of your 6.7L Cummins: the Crankcase Ventilation (CCV) system. If you own a 2007.5-2018 Dodge Ram 2500/3500, and you haven't addressed this, you're slowly but surely letting your engine bathe in its own waste. Harsh? Maybe. True? Absolutely.
I've been running this specific Open Breather Kit for over 15,000 miles now, through towing seasons, bitter winters, and dusty summers. This isn't a sponsored post; this is a "why-didn't-I-do-this-sooner" revelation that I feel obligated to share with the community. We're going deep – consider this your one-stop guide to understanding the "why," the "how," and the "which" of CCV reroutes.
Part 1: The "Why" – The Dirty Secret of Your Closed CCV System
From the factory, our 6.7L Cummins engines use a closed crankcase ventilation system. Here’s the simple, problematic idea: blow-by gases (a mix of combustion pressure, unburned fuel, acidic moisture, and microscopic oil droplets) are sucked out of the crankcase and fed directly back into the intake stream, right before the turbocharger.
The theory is environmental and "clean": burn those vapors instead of venting them to the atmosphere. The reality is a mechanical nightmare:
Part 2: The "Solution" – Enter the Open Breather Kit
The fix is elegantly simple: intercept those harmful vapors before they reach the intake and vent them safely to the atmosphere (or to a catch can first). This converts the problematic closed system into a reliable open system. The specific TruckTok CCV Black Crankcase Ventilation Open Breather Kit I installed is a perfect example of this solution done right.
What's in the Box & Key Features:
This isn't some janky parts-store special. The quality is immediately apparent:
I'm not a professional mechanic, and I found this to be one of the easiest mods I've ever done. Basic hand tools are all you need (wrenches, sockets, maybe a pair of pliers).
Part 4: The Results & Real-World Observations
The difference isn't a "seat-of-the-pants" power increase. It's a health and cleanliness increase.
The Open Breather Kit is a mandatory first mod for any serious 6.7L Cummins owner. It's not about making peak power; it's about preserving the power you have, protecting your four-figure investments (turbo, intercooler), and ensuring long-term reliability.
Who needs it?
Feel free to ask any questions below. I'll do my best to answer based on my experience.
I've been running this specific Open Breather Kit for over 15,000 miles now, through towing seasons, bitter winters, and dusty summers. This isn't a sponsored post; this is a "why-didn't-I-do-this-sooner" revelation that I feel obligated to share with the community. We're going deep – consider this your one-stop guide to understanding the "why," the "how," and the "which" of CCV reroutes.
Part 1: The "Why" – The Dirty Secret of Your Closed CCV System
From the factory, our 6.7L Cummins engines use a closed crankcase ventilation system. Here’s the simple, problematic idea: blow-by gases (a mix of combustion pressure, unburned fuel, acidic moisture, and microscopic oil droplets) are sucked out of the crankcase and fed directly back into the intake stream, right before the turbocharger.
The theory is environmental and "clean": burn those vapors instead of venting them to the atmosphere. The reality is a mechanical nightmare:
- Turbo Coking: That hot, oily vapor cooks onto the cold side (compressor wheel and housing) of your expensive turbo. This buildup, called "coking," acts like grinding paste, robs efficiency, and can eventually lead to turbo shaft play and failure.
- Intercooler Fouling: The oil mist travels through your charge pipes and coats the inside of your intercooler. This oily film is a fantastic insulator, dramatically reducing the intercooler's ability to cool the charged air. Hotter intake air = less power, more EGTs, and lost fuel economy.
- MAP Sensor Contamination: The mass air flow/pressure sensors get gunked up, leading to inaccurate readings and potential performance issues.
- Overall Performance Degradation: It's a slow, cumulative effect. You might not notice it day-to-day, but over tens of thousands of miles, you're leaving horsepower, throttle response, and MPG on the table—or rather, smearing it all over your intake tract.
Part 2: The "Solution" – Enter the Open Breather Kit
The fix is elegantly simple: intercept those harmful vapors before they reach the intake and vent them safely to the atmosphere (or to a catch can first). This converts the problematic closed system into a reliable open system. The specific TruckTok CCV Black Crankcase Ventilation Open Breather Kit I installed is a perfect example of this solution done right.
What's in the Box & Key Features:
This isn't some janky parts-store special. The quality is immediately apparent:
- Reinforced Silicone Hoses: Not cheap rubber that will crack and degrade. These are thick, temperature-resistant silicone hoses. The kit prominently features the 90-degree ventilation hose – this angle is crucial. It's designed not just to route vapor, but to help drain separated oil condensate back toward the crankcase, preventing pooled liquid in the line.
- Proper Fittings and Clamps: All included hose clamps are constant-tension or high-grade worm-drive clamps. No leaking at the connections.
- Breather Filter (Optional on some kits): The end of the line is a small, cleanable filter that allows vapors to escape but blocks debris. Some kits vent to a catch can first; this one goes straight to atmosphere, which is simpler and effective for most users.
I'm not a professional mechanic, and I found this to be one of the easiest mods I've ever done. Basic hand tools are all you need (wrenches, sockets, maybe a pair of pliers).
- Use pliers to remove the hose clamps connected to the ventilation hoses at both ends of the valve cover.
- Follow that same hose down and remove hose clamps that are down towards the turbo. Pull the hose out.Note: If your truck is a 2019+, cut the factory hose near the compressor housing and install the provided plug.
- Press the provided plug into the lower hose connected to the turbine inlet and secure it with a clamp.
- Install the filter onto the 90 degree bend provided in the kit and secure it with clamps.Install the connected filter onto the valve cover of the previously removed ventilation pipe.
Part 4: The Results & Real-World Observations
The difference isn't a "seat-of-the-pants" power increase. It's a health and cleanliness increase.
- Post-Install Inspection: After 5,000 miles, I pulled the intake hose at the turbo. On the stock system, this would already have a sheen of oil. It was bone dry and clean. Absolutely remarkable.
- Intercooler & Throttle Response: While harder to see directly, the science is sound. A clean intercooler works better. I did notice my EGTs were slightly lower (50-75°F) under heavy towing load, indicating more efficient charge cooling. Throttle response feels a tad crisper, likely due to a cleaner MAP sensor and unobstructed airflow.
- Long-Term Maintenance: This mod is essentially maintenance-free. Check the breather filter every oil change, clean it with brake cleaner if it looks dusty, and re-oil it. That's it.
- "Is this legal / a gross polluter?" The amount of hydrocarbons vented is minuscule compared to your tailpipe emissions. The environmental impact of replacing a fouled turbo, intercooler, and associated parts far outweighs this. It's widely accepted in the diesel community.
- "Won't it smell?" Under normal driving, you'll never smell it. At idle, sometimes you might get a faint whiff of crankcase vapors if the wind is just right. It's not a fuel or exhaust smell, and 99% of the time, it's unnoticeable.
- "Should I use a catch can instead?" Catch cans are great, especially for high-boost or competition applications. They add complexity (emptying them) and cost. For the vast majority of daily drivers and tow rigs, a simple, well-designed open breather kit like this is perfectly adequate and more foolproof.
- "Will it hurt my engine?" No. This is how engines breathed for decades. It reduces internal pressure slightly and eliminates a major source of contamination.
The Open Breather Kit is a mandatory first mod for any serious 6.7L Cummins owner. It's not about making peak power; it's about preserving the power you have, protecting your four-figure investments (turbo, intercooler), and ensuring long-term reliability.
Who needs it?
- Anyone who plans to keep their truck past 100,000 miles.
- Anyone who tows or uses their truck for heavy work.
- Anyone who has already tuned their truck (increased blow-by).
- Anyone who simply believes in preventive maintenance.
Feel free to ask any questions below. I'll do my best to answer based on my experience.
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