DFC Diesel SS660104LB7TKSOALB Street Series Speed Of Air Long Block (Standard/Auto) | 2001-2004 GM/Chevrolet 2500HD/3500HD 6.6L Duramax LB7 TOPKICK

Features:

• Fits 2001–2004 TopKick 6.6L LB7 engines
• Backed by 5-year, 160,000 km warranty
• Includes remanufactured long block assembly
• All new OEM-grade internal engine components
• Machined using advanced Rottler equipment
• Professionally bored for oversized pistons
• ARP or OptiTorque head studs installed
• Total Seal gapless piston rings included
• Reman heads with new valves and guides
• Top-end gasket kit included for installation
• EDM doweled oil pump gear for strength
• Camshaft features woodruff key for reliability

Confidence Starts With The Right Foundation Underneath

If your 2001–2004 TopKick is down for the count, the DFC Diesel Street Series Long Block is the kind of replacement that does more than just get you back on the road, it sets you up for the long haul. Built specifically for work-ready applications and daily-driven diesels, this remanufactured 6.6L LB7 engine delivers premium reliability backed by a 5-year, 160,000 km warranty. That means you’re not just buying a motor, you’re investing in peace of mind. Every component inside is brand new, from pistons and rings to gaskets and bearings, so you’re not dealing with leftover wear from an old core. You’ll also get ARP or OptiTorque head studs for increased clamping force, which helps prevent common issues like blown head gaskets under load. It includes a top-end gasket kit to finish off the install, plus the valvetrain comes pre-set to factory specs to simplify the job. Whether your truck’s running tools to a job site or hauling equipment across town, this long block is ready for the demands of hard, everyday use.

Built With Precision For Heavy Duty Performance

The DFC SS660104LB7TKSOALB long block is engineered for the demands of medium-duty trucks like the 2001–2004 GMC TopKick running the 6.6L Duramax LB7 platform. This remanufactured engine is machined using advanced Rottler equipment to ensure consistent, tight tolerances throughout every surface and component. The block is bored to accept next oversized pistons, paired with Total Seal gapless rings that deliver tighter combustion and lower oil consumption. Each set of cylinder heads is resurfaced, magnafluxed, and equipped with all new valves, guides, and stem seals for factory-spec airflow and durability. A woodruff-keyed camshaft adds rotational security, while DFC’s EDM doweled oil pump gear reinforces oil system stability. The long block includes a complete short block, reman heads, and a full top-end gasket kit for easy final assembly. All rockers and pushrods are pre-set to factory specs, reducing installation time and the risk of error during setup. This engine is a perfect match for drivers who need dependable performance and consistent output under load.

Fits: 2001, 2002, 2003, 2004 GM/Chevrolet 2500HD/3500HD 6.6L Duramax LB7

Notes:

• Designed for 2001–2004 GMC TopKick with 6.6L LB7 Duramax
• Intended for daily driving, light towing, and work use
• Street Series engines include upgrades to known LB7 failure points
• Remanufactured using brand new OEM or equivalent components
• All cylinder heads are resurfaced, magnafluxed, and rebuilt
• Includes top-end gasket kit to complete installation
• Valvetrain components pre-set to factory specifications
• ARP or OptiTorque head studs included depending on availability
• Block is machined to accept next oversized pistons
• Built using advanced Rottler machining for consistent tolerances
• Covered by a 5-year or 160,000 km limited warranty
• Professional installation recommended for proper setup and break-in

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.