Cummins Trucks
Cummins Diesel Trucks Built for Heavy Towing and Long-Term Reliability
See our Cummins diesel inventory across Utah, Idaho, and Colorado.
Truck Ranch offers a full lineup of used Ram 2500 and 3500 trucks powered by the legendary Cummins turbo diesel. These trucks are known for unmatched towing capability, extreme torque output, and long engine life. Whether you're hauling a fifth wheel, towing equipment to the job site, or looking for a reliable daily rig, our Cummins inventory is built to deliver.
The 6.7L Cummins I6 is one of the most trusted diesel engines in America, offering exceptional low-end torque and impressive longevity. We stock lifted builds, long-bed crew cabs, and dual-rear-wheel (DRW) trucks—all backed by our diesel reconditioning process.
🔥 Featured Inventory Highlights
- 6.7L Cummins Turbo Diesel trucks in stock
- Ram 2500 & 3500 models with max tow packages
- Manual and automatic transmission builds
- High-output variants with Aisin transmissions
- Low-mileage workhorses and lifted off-roaders
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💬 Customer Praise
"Bought a Cummins Ram 3500 for towing my horse trailer—Truck Ranch made it easy, and the truck was spotless. Pulled strong across state lines like nothing."
– Jenna W., Verified Buyer
🧠 Cummins Diesel Tips Every Owner Should Know
Replace both primary and secondary filters every 15,000 miles to protect your injection system. The Cummins high-pressure fuel system is sensitive to contaminants, and poor filtration can lead to expensive injector or CP3/CP4 pump failures. Watch for head gasket seepage, crankcase pressure, excessive blow-by, or deleted emissions systems. Aftermarket tuners without supporting mods can strain the engine. Also check for transmission slipping on 68RFE models. Use API CJ-4 or CK-4 rated 5W-40 synthetic diesel oil in colder climates or when towing. For transmission fluid, use ATF+4 (68RFE) or ASRC-approved ATF (Aisin). Always follow OEM specs to protect your powertrain warranty. Stick to factory tire sizes, limit idle time, and use cruise control at 65 MPH. A clean EGR, properly functioning DEF system, and factory emissions settings deliver the best MPG. Expect 15–18 MPG highway in real-world use. The Aisin 6-speed automatic is stronger and built for high-output Cummins (up to 1,075 lb-ft of torque). The 68RFE is lighter-duty and more common in 2500 models. If you're towing 15K+ lbs regularly, go Aisin. The Crankcase Ventilation (CCV) filter captures oil vapors before they enter the intake. On the 6.7L Cummins, change it every 67,500 miles per Ram’s maintenance schedule. Neglecting this can clog your turbo or EGR. A properly equipped Ram 3500 with a Cummins HO + Aisin can tow up to 35,100 lbs (gooseneck). Standard Ram 2500 models with 68RFE are rated closer to 17,000–19,000 lbs. Always verify with the door jamb sticker or Ram’s tow chart. 🛢️ When should I replace my Cummins fuel filters?
🚨 What are the top red flags on used Cummins trucks?
🧪 What fluid should I run in a Cummins diesel?
💨 How do I improve MPG on a Ram 2500/3500 Cummins?
⚙️ Which transmission is best: Aisin or 68RFE?
🔧 What is the CCV filter and when do I change it?
🎯 What’s the towing capacity of a Cummins truck?
💡 Your Cummins Diesel Buying Guide
⚖️ Powerstroke vs. Duramax vs. Cummins
🔧 How Truck Ranch Reconditions Every Cummins Diesel
Before any Cummins truck is listed on our site, it goes through a comprehensive diesel inspection and reconditioning process. Our in-house diesel techs evaluate each Ram 2500 and 3500 to ensure you’re getting a truck that performs, lasts, and instills confidence the moment you turn the key.
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Full Powertrain Diagnostic
Scan codes, test compression, check crankcase pressure, and inspect injectors and turbos. - ✅
Fluid Service + Filter Replacement
Oil, fuel, air, and DEF filters replaced if outside spec. Transmission and diff fluids checked and serviced. - ✅
Undercarriage + Steering Safety Check
Inspect ball joints, tie rods, shocks, bushings, and brakes—critical on heavy-duty Rams. - ✅
Road Test Under Load
All trucks are test-driven under towing simulations to monitor shift points, EGTs, and boost. - ✅
Detailing + Final QA
Steam-clean engine bay, shampoo carpets, polish wheels, inspect lights, sensors, and emissions systems before delivery.
This is why Truck Ranch Cummins trucks drive better, last longer, and earn more repeat buyers. You’re not just buying used—you’re buying prepared.
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