{"product_id":"dfc-diesel-th660104lb7soalb-tow-haul-series-speed-of-air-long-block-standard-auto-2001-2004-gm-chevrolet-2500hd-3500hd-6-6l-duramax-lb7","title":"DFC Diesel TH660104LB7SOALB Tow\/Haul Series Speed Of Air Long Block (Standard\/Auto) | 2001-2004 GM\/Chevrolet 2500HD\/3500HD 6.6L Duramax LB7","description":"\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eBuilt for up to 500 horsepower output\u003c\/li\u003e\n\u003cli\u003eIncludes Stage 2 performance camshaft\u003c\/li\u003e\n\u003cli\u003eMahle Motorsports heavy-duty pistons installed\u003c\/li\u003e\n\u003cli\u003eManton HD pushrods for added strength\u003c\/li\u003e\n\u003cli\u003eHD valve springs support higher performance\u003c\/li\u003e\n\u003cli\u003eTotal Seal gapless piston rings standard\u003c\/li\u003e\n\u003cli\u003eScrew-in injector cups improve reliability\u003c\/li\u003e\n\u003cli\u003eCrankshaft dowels for harmonic balancer stability\u003c\/li\u003e\n\u003cli\u003eAll new OEM-grade internal components\u003c\/li\u003e\n\u003cli\u003eARP or OptiTorque head studs included\u003c\/li\u003e\n\u003cli\u003eTop-end gasket kit included with long block\u003c\/li\u003e\n\u003cli\u003eBacked by 5-year, 160,000 km warranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003ePush Your Truck Farther With Confidence Built In\u003c\/h4\u003e\n\u003cp\u003eIf your 2001–2004 Duramax 2500HD or 3500HD needs a serious powerplant upgrade, the DFC Tow\/Haul Series Long Block is built to handle the job. Designed for heavy towing, performance applications, and real-world work trucks, this engine packs premium components and proven durability into every build. Unlike a basic replacement, this long block includes performance-minded upgrades like a Stage 2 camshaft, Mahle Motorsports heavy-duty pistons, and Manton HD pushrods, all engineered to support up to 500 horsepower at the flywheel. You’ll also get the reliability of screw-in injector cups, a known weak point in stock LB7s, and added dowels in the crankshaft to keep your balancer and trigger gear rock-solid. Whether you're hauling loads cross-country or just want peace of mind under the hood, this engine is built to work hard and hold together under pressure. With a 5-year, 160,000 km warranty and nothing but name-brand internals throughout, it’s a serious upgrade for diesel owners who rely on their truck every day. From reliability to raw strength, this long block doesn’t cut corners, and neither should you.\u003c\/p\u003e\n\u003ch4\u003eDesigned To Withstand Torque Heat And Heavy Load\u003c\/h4\u003e\n\u003cp\u003eThe DFC Diesel TH660104LB7SOALB Tow\/Haul Series long block delivers a precision-built solution for 2001–2004 GM and Chevrolet trucks running the 6.6L LB7 Duramax. This engine includes all the upgrades found in DFC’s Street Series models, but steps it up with components chosen for higher horsepower and long-haul towing demands. At the core is a professionally machined and bored block, built to accept oversized pistons and outfitted with Mahle Motorsports HD units for added strength. A Stage 2 camshaft provides better valve timing for power and torque delivery, while Manton HD pushrods and upgraded valve springs improve valvetrain stability under load. Total Seal gapless rings increase compression and reduce blow-by, helping the engine operate efficiently under high stress. Added dowels in the crankshaft stabilize the harmonic balancer and trigger gear assembly, improving long-term engine balance and precision. Screw-in injector cups resolve a common failure point found in early LB7 models, adding peace of mind during extended operation. From daily towing to hard-working commercial use, this long block is engineered to support performance up to 500 HP while keeping durability at the center of its design.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e Fits: \u003c\/strong\u003e 2001, 2002, 2003, 2004 GM\/Chevrolet 2500HD\/3500HD 6.6L Duramax LB7\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eNotes:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eDesigned for 2001–2004 GM\/Chevrolet 2500HD and 3500HD with 6.6L Duramax LB7\u003c\/li\u003e\n\u003cli\u003eTow\/Haul Series is ideal for towing and performance applications\u003c\/li\u003e\n\u003cli\u003eRated to support up to 500 horsepower at the flywheel\u003c\/li\u003e\n\u003cli\u003eIncludes all upgrades found in the Street Series long block\u003c\/li\u003e\n\u003cli\u003eFeatures Mahle Motorsports heavy-duty pistons for added strength\u003c\/li\u003e\n\u003cli\u003eIncludes Stage 2 performance camshaft for improved power delivery\u003c\/li\u003e\n\u003cli\u003eEquipped with Manton HD pushrods and heavy-duty valve springs\u003c\/li\u003e\n\u003cli\u003eCrankshaft includes added dowels for harmonic balancer stability\u003c\/li\u003e\n\u003cli\u003eLB7 variant includes screw-in injector cups to prevent common failure\u003c\/li\u003e\n\u003cli\u003eBlock is professionally machined and bored for oversized pistons\u003c\/li\u003e\n\u003cli\u003eRemanufactured using all new OEM or equivalent internal components\u003c\/li\u003e\n\u003cli\u003eBacked by a 5-year or 160,000 km limited warranty\u003c\/li\u003e\n\u003cli\u003eProfessional installation and proper engine break-in strongly recommended\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 data-start=\"884\" data-end=\"931\"\u003eStreet Series vs Tow\/Haul vs Tow\/Haul HD\u003c\/h3\u003e\n\u003cul data-start=\"933\" data-end=\"1398\"\u003e\n\u003cli data-start=\"933\" data-end=\"1099\"\u003e\n\u003cp data-start=\"935\" data-end=\"1099\"\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-start=\"1100\" data-end=\"1240\"\u003e\n\u003cp data-start=\"1102\" data-end=\"1240\"\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-start=\"1241\" data-end=\"1398\"\u003e\n\u003cp data-start=\"1243\" data-end=\"1398\"\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-start=\"1405\" data-end=\"1445\"\u003eStandard\/Auto vs Standard vs Auto\u003c\/h3\u003e\n\u003cul data-start=\"1447\" data-end=\"1706\"\u003e\n\u003cli data-start=\"1447\" data-end=\"1557\"\u003e\n\u003cp data-start=\"1449\" data-end=\"1557\"\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-start=\"1558\" data-end=\"1636\"\u003e\n\u003cp data-start=\"1560\" data-end=\"1636\"\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-start=\"1637\" data-end=\"1706\"\u003e\n\u003cp data-start=\"1639\" data-end=\"1706\"\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":68060705489169,"sku":"DDU-TH660104LB7SOALB","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_c87d5f69-4974-4ce7-be87-0392d9cf4f3b.jpg?v=1794721792","url":"https:\/\/gautoparts.com\/products\/dfc-diesel-th660104lb7soalb-tow-haul-series-speed-of-air-long-block-standard-auto-2001-2004-gm-chevrolet-2500hd-3500hd-6-6l-duramax-lb7","provider":"Guaranteed Auto Parts","version":"1.0","type":"link"}