DFC Diesel SS6604505LLYTKSOALB Street Series Speed Of Air Long Block (Standard/Auto) | 2004.5-2005 GM/Chevrolet 2500HD/3500HD 6.6L Duramax LLY TOPKICK

Features:

• Fits 2004.5-2005 6.6L LLY TopKick models
• 5-year, 160,000 km limited warranty coverage
• Remanufactured to exceed OEM specifications
• Built for daily driving and light towing
• Includes ARP or OptiTorque head studs
• All-new pistons, rings, and bearings
• Fully rebuilt and resurfaced cylinder heads
• Includes Total Seal gapless piston rings
• Woodruff keyed camshaft improves long-term durability
• Machined with advanced Rottler equipment
• Improved gasket sealing in leak-prone areas
• Drop-in long block with top end gasket kit

Give Your TopKick The Heart It Deserves

If your 2004.5-2005 TopKick has been giving you signs of engine fatigue or failure, this DFC Street Series Long Block is built to bring it back stronger than ever. Whether you're hauling gear, plowing snow, or just keeping your workhorse alive, this long block gives you the peace of mind that your Duramax LLY is ready for anything. It's not a basic rebuild, DFC takes the time to correct known weak points in these engines with proven upgrades, like ARP or OptiTorque head studs, improved sealing in common leak areas, and top-grade internal parts. You're getting all-new pistons, rings, gaskets, and bearings straight out of the box, so there’s no guesswork involved. DFC doesn’t cut corners, and that’s why they back this engine with a 5-year, 160,000 km warranty. It’s built for those who rely on their truck to work hard without letting them down. Whether you're clocking miles on the job site or putting it to the test in the field, this is the kind of upgrade that delivers confidence every time you turn the key.

Engineered To Handle Workload Without Breaking A Sweat

This Street Series Long Block from DFC is a precision-built solution for the 6.6L Duramax LLY in your 2004.5-2005 TopKick, designed with durability and reliability at its core. Every engine is remanufactured using state-of-the-art Rottler machining to ensure consistent tolerances throughout the block and heads. The cylinder heads are completely rebuilt with new valves, seats, guides, and stem seals, then resurfaced and magnafluxed for structural integrity. Inside, you'll find Total Seal gapless piston rings for improved compression and oil control, plus a DFC EDM doweled oil pump gear and woodruff keyed camshaft to strengthen critical areas of the rotating assembly. The block is bored for the next oversize piston, ensuring a clean and proper fit with all-new internal components. Rockers and pushrods are pre-set to factory spec, and a complete top-end gasket kit is included to make installation smoother. This isn’t just a long block, it’s a fully thought-out platform that restores and enhances engine performance with every detail dialed in for long-term use.

Fits: 2004.5, 2005 GM/Chevrolet 2500HD/3500HD 6.6L Duramax LLY

Notes:

• Engine is built specifically for 2004.5-2005 GM/Chevy TopKick trucks with the 6.6L Duramax LLY
• Street Series is best suited for daily driving, light-duty towing, and general work applications
• All components are new or remanufactured to meet or exceed OEM specs
• Engine includes complete long block with short block, cylinder head, and top-end gasket kit
• Head studs may be ARP or OptiTorque, depending on availability
• Warranty coverage includes 5 years or 160,000 km (100,000 miles)
• Cylinder heads are fully rebuilt with new seats, guides, and valves
• Block is machined for next oversize piston fitment
• This is not a complete engine, external components like turbo, fuel system, and ECM are not included
• Professional installation is strongly recommended to ensure optimal performance and reliability

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.