DFC Diesel TH6707518SOALBHD Tow/Haul HD Series Standard/Auto Speed Of Air Long Block | 2007.5-2018 Dodge RAM 6.7L Cummins

Features:

• Built To Handle Up To 850 Horsepower
• Includes Wagler Forged Connecting Rods
• Features Fluidamper Harmonic Balancer
• Comes With Heavy-Duty Flexplate
• Balanced Rotating Assembly Installed
• O-Ringed Cylinder Head Included
• Stage 4 Camshaft For Enhanced Performance
• Total Seal Gapless Piston Rings
• Ceramic-Coated Piston Crowns For Heat Resistance
• Dry Film Coated Skirts For Durability
• ARP 2000 Or OptiTorque Head Studs
• 5-Year / 100,000 Mile Warranty Included

When You Need A Cummins That Can Take It All

If you're pushing your truck to its limits and need an engine that doesn't flinch under pressure, the DFC Tow/Haul HD Series Long Block is exactly what you're after. Built for the guy who's towing heavy loads all week and still wants to light it up on the weekend, this engine delivers the kind of performance and durability few others can touch. It’s designed to handle up to 850 horsepower at the flywheel, so you’ve got plenty of headroom whether you’re hauling equipment or dialing up your tune. What really sets this build apart is the internal reinforcement, it comes with premium Wagler connecting rods, a Fluidamper to control harmonics, and a heavy-duty flexplate that’s ready for serious torque. The rotating assembly is fully balanced to keep things smooth and reliable even when you're running hard for long stretches. All the proven upgrades from the Street and Tow/Haul Series are here too, which means you're not missing anything when it comes to everyday drivability. This is a long block that doesn't compromise, it’s built to handle the heat, the stress, and the long haul.

Every Component Inside This Build Has A Purpose

The Tow/Haul HD Series is the most robust 6.7L Cummins long block DFC offers, combining high-strength internals with exacting machine work for serious power and longevity. It starts with a professionally machined block using Rottler CNC equipment, bored to accept next-over-sized pistons that are ceramic-coated on the crowns and dry film coated on the skirts. These coatings improve heat resistance and reduce friction in demanding conditions, like extended towing or stop-and-go traffic with a full trailer. The engine includes an O-ringed cylinder head and a Cometic MLS gasket set to help seal combustion pressures, especially at higher boost levels. Inside, you’ll find a Stage 4 camshaft and Manton heavy-duty pushrods paired with 103lb valve springs, giving the valvetrain the strength it needs to maintain timing and stability under high load. The addition of Wagler connecting rods significantly increases bottom-end durability, and the Fluidamper helps minimize harmful engine vibrations over time. Every part of this build is there for a reason, to create a reliable, high-output long block that works as hard as you do.

Fits: 2007.5, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018 Dodge RAM 6.7L Cummins

Notes:

• Designed for 2007.5-2018 6.7L Dodge Cummins trucks
• Rated to handle up to 850 HP at the flywheel
• Best suited for towing and hauling between 500-750 HP
• Includes all upgrades from Street and Tow/Haul Series engines
• Engine is remanufactured using new OEM or equivalent components
• Built with Wagler forged connecting rods for added strength
• Includes a Fluidamper to help reduce engine harmonics
• Comes with a heavy-duty flexplate for high torque use
• Rotating assembly is balanced for smoother performance
• Long block does not include fuel system, turbo, or electronics
• Head studs may be ARP 2000 or OptiTorque based on availability
• Backed by a 5 year / 100,000 mile (160,000 km) warranty

Street Series vs Tow/Haul vs Tow/Haul HD

• Street Series: Ideal for daily driving, light work, and diesel enthusiasts. Focuses on reliability upgrades over stock, with head stud and sealing improvements.

• Tow/Haul Series: All Street upgrades plus added performance parts for higher load and towing power. Supports builds up to ~700 HP.

• Tow/Haul HD Series: The most robust option. Adds heavy-duty internals like Wagler rods and a balanced rotating assembly for 800+ HP capability.

Standard/Auto vs Standard vs Auto

• Standard/Auto: Compatible with both manual and automatic transmissions. Offers the most flexibility.

• Standard: Built specifically for manual transmission configurations.

• Auto: Built specifically for automatic transmission setups.