DFC Diesel TH6607510LMMSOALB Tow Haul Series Speed Of Air Long Block (Standard/Auto) | 2007.5-2010 GM/Chevrolet 2500HD/3500HD 6.6L Duramax LMM

Features:

• Built for towing and hauling up to 500HP
• Includes Stage 2 performance camshaft upgrade
• Heavy-duty Mahle Motorsports forged pistons
• Manton HD pushrods for added valve stability
• HD valve springs support higher RPM control
• Crankshaft doweled for harmonic balancer
• Trigger gear assembly doweled for reliability
• Comes with ARP or OptiTorque head studs
• Total Seal gapless piston rings standard
• Includes full top-end gasket kit
• Pre-set rockers and pushrods to factory spec
• Backed by 5-year, 160,000 km warranty

Tow With Confidence And Power You Can Trust

If your Duramax has seen better days and your workload isn’t slowing down, the DFC Tow/Haul Series Long Block is exactly what your 2007.5 to 2010 2500HD or 3500HD needs to get back in the game. This engine isn’t just rebuilt, it’s purpose-built for trucks that tow, haul, and work hard day in and day out. DFC took everything they engineered into their Street Series and stepped it up with upgrades designed specifically for durability under load and performance up to 500 horsepower. Mahle Motorsports heavy-duty pistons, Manton HD pushrods, and upgraded valve springs give this long block the backbone it needs to handle stress without backing down. It also includes a Stage 2 camshaft for more efficient torque delivery, especially helpful when pulling trailers or climbing grades. This engine is made for guys who need their truck to pull hard, stay cool, and stay running. It’s backed by a 5-year, 160,000-kilometer warranty, giving you the confidence to hitch up and haul without hesitation.

Engineered For High Load Performance And Long Term Strength

The DFC Diesel TH6607510LMMSOALB Tow/Haul Series Long Block is a fully remanufactured 6.6L Duramax LMM designed for consistent power delivery under load. This package includes everything from DFC’s Street Series, plus essential upgrades for high-output towing and long-term reliability. The block is professionally machined to accept next oversized pistons and is fitted with Mahle HD units known for superior heat and pressure tolerance. A Stage 2 camshaft increases lift and duration for improved low-end torque, making it ideal for heavy trailers and fifth-wheel applications. The crankshaft is doweled for both the harmonic balancer and trigger gear assembly, reducing slippage and maintaining precise timing under high-stress conditions. Manton pushrods and HD valve springs strengthen the valvetrain to hold up under elevated RPM and load. ARP or OptiTorque head studs are included to keep everything sealed tight, even under boost. With a complete top-end gasket kit and valvetrain components set to spec, this engine is installation-ready and built to take punishment mile after mile.

Fits: 2007.5, 2008, 2009, 2010 GM/Chevrolet 2500HD/3500HD 6.6L Duramax LMM

Notes:

• Designed for 2007.5–2010 6.6L Duramax LMM engines
• Fits GM 2500HD and 3500HD with standard or automatic transmissions
• Engine is a long block configuration, not a complete crate engine
• Rated for towing, hauling, and performance up to 500 horsepower
• Includes all upgrades found in the Street Series model
• Built with heavy-duty internal components for added strength
• Fuel system, turbocharger, and electronics are not included
• Comes with full top-end gasket kit for final assembly
• All valvetrain components are pre-set to factory specifications
• Crankshaft includes added dowels for harmonic balancer and trigger gear
• Core return may be required to complete purchase
• Professional installation is strongly recommended
• Covered by DFC's 5-year or 160,000 kilometer 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.