{"product_id":"dfc-diesel-th6604505llysoalb","title":"DFC Diesel TH6604505LLYSOALB Tow\/Haul Series Speed Of Air Long Block (Standard\/Auto) | 2004.5-2005 GM\/Chevrolet 2500HD\/3500HD 6.6L Duramax LLY","description":"\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eBuilt for 2004.5-2005 Duramax LLY trucks\u003c\/li\u003e\n\u003cli\u003eRated for towing and hauling up to 500HP\u003c\/li\u003e\n\u003cli\u003eIncludes all Street Series performance upgrades\u003c\/li\u003e\n\u003cli\u003eStage 2 camshaft for improved torque delivery\u003c\/li\u003e\n\u003cli\u003eMahle Motorsports heavy-duty pistons included\u003c\/li\u003e\n\u003cli\u003eManton HD pushrods increase valve train strength\u003c\/li\u003e\n\u003cli\u003eHD valve springs support higher performance loads\u003c\/li\u003e\n\u003cli\u003eARP or OptiTorque head studs for better sealing\u003c\/li\u003e\n\u003cli\u003eAdded crankshaft dowels for better balancer stability\u003c\/li\u003e\n\u003cli\u003eIncludes Total Seal gapless piston rings\u003c\/li\u003e\n\u003cli\u003eFully remanufactured to exceed OEM specifications\u003c\/li\u003e\n\u003cli\u003eCovered by 5-year, 160,000 km limited warranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eTow With Confidence And Drive With Purpose\u003c\/h4\u003e\n\u003cp\u003eIf your 2004.5-2005 Duramax-powered 2500HD or 3500HD needs a serious upgrade to match the demands of heavy hauling or daily driving, the DFC Tow\/Haul Series Long Block is the engine you’ve been waiting for. This build isn’t just about replacing what's worn out, it's about giving your truck the muscle it deserves. Designed to handle up to 500 horsepower, this long block includes all the proven upgrades of DFC’s Street Series, plus a few heavy-duty reinforcements built specifically for towing and performance. With Mahle HD pistons, Manton pushrods, and a Stage 2 camshaft, this engine delivers better power, smoother throttle response, and more durability under load. Whether you're pulling equipment through steep grades or towing a fifth-wheel across state lines, you can trust this engine to stay cool, strong, and consistent. It’s built by diesel professionals who understand the abuse these trucks take on the job. Backed by a 5-year, 160,000 km warranty, this is the kind of upgrade that turns your truck into a true workhorse.\u003c\/p\u003e\n\u003ch4\u003eHeavy Duty Engineering For High Load Performance\u003c\/h4\u003e\n\u003cp\u003eThe DFC Diesel TH6604505LLYSOALB Tow\/Haul Series Long Block is engineered for the 2004.5-2005 6.6L Duramax LLY platform and is rated for up to 500 horsepower at the flywheel. This long block includes all the Street Series enhancements plus key towing-specific upgrades that make it ideal for trucks used in high-demand environments. The block is professionally machined to tight tolerances, fitted with Mahle Motorsports heavy-duty pistons, and assembled with Total Seal gapless piston rings for maximum compression and oil control. A Stage 2 camshaft increases mid-range torque, while Manton HD pushrods and heavy-duty valve springs reinforce valvetrain stability at higher loads. DFC also includes added dowel pins in the crankshaft for better alignment of the harmonic balancer and trigger gear assembly, helping maintain long-term crank stability. ARP or OptiTorque head studs are included depending on availability, offering enhanced clamping force to prevent head lift under boost. Every engine comes with a full top-end gasket kit and pre-set valvetrain components, making install efficient and precise. This long block is ideal for serious diesel owners who demand performance without sacrificing reliability.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e Fits: \u003c\/strong\u003e 2004.5, 2005 GM\/Chevrolet 2500HD\/3500HD 6.6L Duramax LLY\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eNotes:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eDesigned specifically for 2004.5-2005 GM\/Chevy 2500HD and 3500HD trucks with the 6.6L Duramax LLY engine\u003c\/li\u003e\n\u003cli\u003eTow\/Haul Series is ideal for heavy towing, work applications, and trucks pushing up to 500HP\u003c\/li\u003e\n\u003cli\u003eIncludes all upgrades from the Street Series for improved reliability and performance\u003c\/li\u003e\n\u003cli\u003eFeatures Mahle Motorsports heavy-duty pistons for added strength under load\u003c\/li\u003e\n\u003cli\u003eComes with a Stage 2 camshaft for enhanced torque and throttle response\u003c\/li\u003e\n\u003cli\u003eEquipped with Manton heavy-duty pushrods and HD valve springs for valvetrain reinforcement\u003c\/li\u003e\n\u003cli\u003eCrankshaft includes added dowels for balancer and trigger gear alignment\u003c\/li\u003e\n\u003cli\u003eIncludes ARP or OptiTorque head studs depending on availability\u003c\/li\u003e\n\u003cli\u003eAll internal components are new or exceed OEM spec standards\u003c\/li\u003e\n\u003cli\u003eEngine is machined and assembled to precise tolerances using advanced Rottler equipment\u003c\/li\u003e\n\u003cli\u003eRated flywheel horsepower matches factory measurement standards\u003c\/li\u003e\n\u003cli\u003eBacked by DFC's 5-year or 160,000 km limited warranty for peace of mind\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 data-end=\"931\" data-start=\"884\"\u003eStreet Series vs Tow\/Haul vs Tow\/Haul HD\u003c\/h3\u003e\n\u003cul data-end=\"1398\" data-start=\"933\"\u003e\n\u003cli data-end=\"1099\" data-start=\"933\"\u003e\n\u003cp data-end=\"1099\" data-start=\"935\"\u003e\u003cspan style=\"text-decoration: underline;\"\u003eStreet Series:\u003c\/span\u003e Ideal for daily driving, light work, and diesel enthusiasts. Focuses on reliability upgrades over stock, with head stud and sealing improvements.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-end=\"1240\" data-start=\"1100\"\u003e\n\u003cp data-end=\"1240\" data-start=\"1102\"\u003e\u003cstrong\u003e\u003cspan style=\"text-decoration: underline;\"\u003eTow\/Haul Series:\u003c\/span\u003e All Street upgrades plus added performance parts for higher load and towing power. Supports builds up to ~700 HP.\u003c\/strong\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-end=\"1398\" data-start=\"1241\"\u003e\n\u003cp data-end=\"1398\" data-start=\"1243\"\u003e\u003cspan style=\"text-decoration: underline;\"\u003eTow\/Haul HD Series:\u003c\/span\u003e The most robust option. Adds heavy-duty internals like Wagler rods and a balanced rotating assembly for 800+ HP capability.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 data-end=\"1445\" data-start=\"1405\"\u003eStandard\/Auto vs Standard vs Auto\u003c\/h3\u003e\n\u003cul data-end=\"1706\" data-start=\"1447\"\u003e\n\u003cli data-end=\"1557\" data-start=\"1447\"\u003e\n\u003cp data-end=\"1557\" data-start=\"1449\"\u003e\u003cstrong\u003e\u003cspan style=\"text-decoration: underline;\"\u003eStandard\/Auto:\u003c\/span\u003e Compatible with both manual and automatic transmissions. Offers the most flexibility.\u003c\/strong\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-end=\"1636\" data-start=\"1558\"\u003e\n\u003cp data-end=\"1636\" data-start=\"1560\"\u003e\u003cspan style=\"text-decoration: underline;\"\u003eStandard:\u003c\/span\u003e Built specifically for manual transmission configurations.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-end=\"1706\" data-start=\"1637\"\u003e\n\u003cp data-end=\"1706\" data-start=\"1639\"\u003e\u003cspan style=\"text-decoration: underline;\"\u003eAuto\u003c\/span\u003e: Built specifically for automatic transmission setups.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"DFC Diesel","offers":[{"title":"Default Title","offer_id":68060705292561,"sku":"DDU-TH6604505LLYSOALB","price":18653.52,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0692\/0477\/1089\/files\/dfc-diesel-long-block-crate-engine-2001-2004-gm-6.6l-lb7-duramax-660104lb7lb__48046_a8e5f918-340b-40f4-873a-6698341fe16c.jpg?v=1794721783","url":"https:\/\/gautoparts.com\/products\/dfc-diesel-th6604505llysoalb","provider":"Guaranteed Auto Parts","version":"1.0","type":"link"}