DFC Diesel TH5904507AUSOALB Tow/Haul Series Auto Speed Of Air Long Block | 2004.5-2007 Dodge RAM 5.9L Cummins

Features:

• Built for towing and heavy-duty hauling
• Supports performance builds up to 700 HP
• Includes ARP or OptiTorque head studs
• Cometic multi-layer steel head gasket
• Stage 3 camshaft for added power
• Heavy-duty Manton push rods included
• Upgraded 60lb or 103lb valve springs
• Total Seal gapless piston rings
• Ceramic coated piston crowns
• Dry film piston skirt coating
• 5-year, 160,000 km limited warranty
• Professionally machined to factory specs

Take On Heavy Loads Without Breaking A Sweat

When you’re pulling weight day in and day out, you need an engine that won’t flinch under pressure. The DFC Diesel Tow/Haul Series Long Block for the 2004.5-2007 5.9L Dodge Cummins is purpose-built for serious towing and hauling without sacrificing durability. Designed for work trucks and performance-focused builds, this long block handles up to 700 horsepower thanks to a host of internal upgrades. It features Total Seal gapless piston rings for maximum compression and power, while ceramic-coated piston crowns help manage heat during heavy pulls. Whether you're towing a loaded trailer across the mountains or stacking miles on the job site, this engine delivers the muscle and reliability you need. With heavy-duty valve springs and a Stage 3 camshaft, throttle response stays crisp even under load. And it’s all backed by a 5-year, 160,000 km warranty that gives you real peace of mind when the work gets tough.

Engineered For Longevity And Built To Perform

This isn’t just a rebuilt motor, it’s a precision-crafted long block designed to exceed OEM expectations. The DFC Diesel Tow/Haul Series is CNC-machined using Rottler equipment to ensure factory-spec tolerances from top to bottom. The assembly includes a fully machined block with over-sized pistons, new OEM or equivalent gaskets, and a reconditioned cylinder head featuring all-new valves, guides, and seats. ARP Series 2000 or OptiTorque head studs secure the top end, paired with a Cometic MLS gasket set to prevent head lift under boost. The Stage 3 camshaft and Manton HD push rods ensure valvetrain stability across the rev range, especially when running heavy or under increased cylinder pressure. Ceramic coatings on the pistons and dry film lubrication on the skirts reduce friction and extend lifespan under high-stress conditions. With components that balance strength and performance, this long block is built to run hard and run long.

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

Notes:

• Built specifically for 2004.5-2007 5.9L Dodge Cummins engines
• Designed for trucks requiring up to 700 HP output
• Intended for heavy towing and performance applications
• Includes both short block and reconditioned cylinder head
• All components are remanufactured to exceed OEM specs
• Uses all new name-brand internal parts, not refurbished
• Comes with a 5-year or 160,000 km limited warranty
• Head studs brand (ARP or OptiTorque) depends on availability
• Valve spring weight varies by engine model year
• Requires proper break-in and installation procedures
• Built with gapless piston rings for better compression
• Machined using Rottler CNC for maximum precision

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.