DFC Diesel TH5904507STSOALBHD Tow/Haul HD Series Standard Speed Of Air Long Block | 2004.5-2007 Dodge RAM 5.9L Cummins

Features:

• Supports up to 900 horsepower output
• Includes heavy-duty Wagler connecting rods
• Balanced rotating assembly for smooth operation
• Fluidamper helps control engine vibration
• Comes with HD flexplate for drivetrain strength
• Designed for standard transmission setups
• Built for high-power street and towing use
• Machined with Rottler CNC for precision
• All internals are new OEM or better
• Cylinder heads resurfaced and magnafluxed
• Includes complete top-end gasket kit
• Backed by 5-year or 160,000 km warranty

Built For The Daily Grind And Weekend Thrills

When your truck does double duty as a workhorse and a powerhouse, the DFC Tow/Haul HD Series Standard Long Block is built to keep up. Designed for 2004.5-2007 5.9L Dodge Cummins trucks, this long block delivers serious strength for street-driven builds that tow heavy and demand performance. Whether you're hauling equipment during the week or pushing big power at the track, this engine handles it all without breaking a sweat. It comes packed with heavy-duty upgrades like Wagler connecting rods, a balanced rotating assembly, and a Fluidamper that all work together to keep things running smooth at high horsepower levels. This build is rated for up to 900 HP, giving you the confidence to dial things up when the job or trail demands more. And since it’s the Standard version, it’s set up for manual transmissions, offering tighter control and more direct power delivery. With DFC’s 5-year, 160,000 km warranty behind it, you can push this engine hard knowing it's ready for the long haul.

Reinforced Internals Deliver Street Ready High Horsepower

Underneath the surface, the DFC Tow/Haul HD Series Standard Long Block is precision built for high-horsepower applications that still see daily street use. Every unit begins with a professionally machined block, bored for over-sized pistons and assembled with all new name-brand internals that meet or exceed OEM standards. The cylinder head is fully remanufactured with new valves, guides, seats, and seals, then magnafluxed and resurfaced to ensure long-term durability. Unique to the HD Series, this version features Wagler connecting rods for added strength under load, a balanced rotating assembly to maintain stability at high RPMs, and a Fluidamper to help reduce harmonic vibration. An HD flexplate adds drivetrain reinforcement, especially useful for trucks that tow or operate under constant stress. It includes everything needed for a complete install, from preset valvetrain components to a full top-end gasket kit. Built for 900 HP but perfectly suited for reliable power in the 650-800 HP range, this long block is a serious foundation for your next high-performance diesel build.

Fits:  2004.5, 2005, 2006, 2007 Dodge RAM 5.9L Cummins

Notes:

• Designed for 2004.5-2007 5.9L Dodge Cummins engines
• Built for standard (manual) transmission setups only
• Rated for up to 900 HP (94-98) and 850 HP (98.5-02)
• Best suited for use between 650-800 HP applications
• Includes all features of Street and Tow/Haul Series engines
• Equipped with Wagler connecting rods for high strength
• Includes Fluidamper and HD flexplate for driveline support
• Balanced rotating assembly ensures smoother high-RPM operation
• All engine internals are new and meet or exceed OEM specs
• Fully remanufactured and resurfaced cylinder head included
• Machined using Rottler CNC for maximum precision
• Covered by a 5-year or 160,000 km limited 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.