Few engines in the diesel world have earned the loyalty, reputation, and staying power of the 6.7L Cummins.
Found in Ram 2500 and 3500 trucks from 2007.5 to present, the 6.7 Cummins has become a favorite among diesel enthusiasts, farmers, contractors, and performance builders alike.
It combines incredible torque, legendary durability, and modern drivability — a balance that’s hard to beat in any heavy-duty truck platform.
Here’s a deep dive into what makes the 6.7 Cummins so popular, how it evolved, and the best upgrades to make it even better.
When the 6.7 Cummins Was Introduced
The 6.7L Cummins was introduced in 2007.5 as a replacement for the 5.9L Cummins. It was designed to meet stricter emissions standards while improving performance and drivability.
From the start, it offered more horsepower and torque — with early models producing 350 HP and 650 lb-ft of torque — while later versions surpassed 400 HP and 1,000 lb-ft.
Since its debut, the 6.7 Cummins has powered every heavy-duty Ram diesel truck, evolving through multiple generations of technology and tuning, while keeping the same basic inline-six design that Cummins fans love.
Technical Features That Set It Apart
The 6.7 Cummins isn’t just powerful — it’s engineered for serious work. Some of its standout mechanical and technical features include:
- Inline-Six Design: Fewer moving parts, better balance, and incredible torque characteristics.
- High-Pressure Common Rail Injection: Provides precise fuel delivery and improved efficiency.
- Variable Geometry Turbo (VGT): Adjustable vanes for better low-end response and towing performance.
- Cast-Iron Block & Head: Built for strength and heat resistance under heavy loads.
- Forged-Steel Crankshaft: Known for handling big power builds with ease.
- Modern Electronics: Integrates advanced ECM control for smoother operation and emissions compliance.
Together, these features make the 6.7 Cummins a powerhouse capable of heavy towing, long-term reliability, and massive performance potential when modified.
Please Note: FASS Motorsports does not under any circumstance sell, offer, promote, or install emissions-off performance parts. This article is for informational purposes only.
Why Truck Owners Love the 6.7 Cummins
There are plenty of reasons diesel fans remain loyal to the 6.7 platform:
- Proven Reliability: Known to last well beyond 300,000 miles with proper maintenance.
- Towing Power: Easily pulls heavy trailers, RVs, and equipment with minimal strain.
- Tuning Potential: Responds extremely well to tuning, turbo upgrades, and fueling improvements.
- Aftermarket Support: Parts availability for performance and reliability upgrades is unmatched.
- Simple, Strong Design: Cummins kept the mechanical durability of older designs while modernizing its performance.
From daily drivers and work trucks to show builds and drag trucks, the 6.7 Cummins remains one of the most versatile diesel engines ever made.
Common 6.7 Cummins Upgrades
Even though the 6.7 is tough from the factory, a few key upgrades can make it perform even better and last longer. At FASS Motorsports, these are the most popular upgrades we recommend for power, reliability, and drivability:
- FASS Fuel System: Provides superior fuel filtration, removes air/vapor from diesel, and protects the high-pressure injection pump.
- Turbo Upgrades: Many owners opt for 2nd Gen swap kits with S300 or S400 frame turbos for improved spool and airflow.
- Custom Tuning: Tuning solutions for pre-encrypted ECMs (2010–2018 trucks) can improve throttle response, fuel economy, and towing power.
- Transmission Builds: Upgraded torque converters, valve bodies, and billet internals for 68RFE or 48RE swaps to handle added power.
- Exhaust & Intake Systems: Lower EGTs, better sound, and improved performance.
- Suspension Upgrades: Carli, BDS, or PMF kits for improved ride, handling, and leveling.
With these upgrades, a well-maintained 6.7 Cummins can reliably make 500–800 HP while staying streetable and capable of daily work duties.
Common 6.7 Cummins Issues
While the 6.7 is durable, there are a few known issues owners should be aware of:
- Fuel System Failures: Earlier models (2019 and prior) used a CP4 pump that can fail and send debris through the entire system — many owners install **S&S Disaster Prevention Kits** or upgrade to a **CP3 retrofit**.
- Turbo Actuator Problems: The electronic actuator can fail over time, especially under high heat cycles.
- EGR & DPF Maintenance: Keeping these systems clean and serviced is key to long-term reliability.
Thankfully, the aftermarket offers proven fixes for nearly every weak point, which is one reason this engine continues to thrive among performance enthusiasts.
FASS Motorsports: Your 6.7 Cummins Experts
At FASS Motorsports in Washington, Missouri, we help diesel owners get the most out of their trucks — from FASS Fuel Systems and turbo kits to suspension upgrades, lighting, and installation.
ggemWe serve Franklin County and the Greater St. Louis area with trusted parts, expert service, and a passion for diesel performance.
👉 Shop 6.7 Cummins parts online
👉 Visit our Washington, MO showroom for professional installation and support
Questions? We’re Here to Help.
- Phone: (636) 429-7020
- Email: info@fassmotorsports.com
FASS Motorsports
25 Town and Country Drive
Washington, MO 63090
