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DFC Diesel KORE660104LB7LB Kore Series Long Block (STD/Auto) | 2001-2004 GM Sierra/Silverado 2500HD/3500HD 6.6L Duramax LB7

DFC Diesel KORE660104LB7LB Kore Series Long Block (STD/Auto) | 2001-2004 GM Sierra/Silverado 2500HD/3500HD 6.6L Duramax LB7

by DFC Diesel
SKU DDU-KORE660104LB7LB
$6,501.85 - $6,501.85
$6,501.85
$6,501.85 - $6,501.85
$6,501.85
Product Availability
  • Ships Directly From The Manufacturer
    You will be contacted with a ship date
    Ships From Manufacturer

Features:

  • Remanufactured long block crate engine
  • Total Seal gapless piston rings included
  • For use with automatic and manual transmission
  • Professionally machined using Rottler equipment
  • Tighter tolerances than OEM specifications
  • All new pistons, rings, bearings, and gaskets
  • New valves, springs, hardened seats, and guides
  • Improved gasket sealing in common leak areas
  • Built in ISO 9001:2015 certified facility
  • 1 year unlimited mileage warranty

An Affordable Path Back To A Dependable LB7

A failed LB7 Duramax doesn't have to mean an expensive engine replacement or a risky gamble on a used unit. The DFC Diesel KORE Series Long Block was built specifically to bridge that gap, giving 2001-2004 GM Silverado and Sierra 2500HD and 3500HD owners a quality remanufactured engine at a more accessible price point. DFC keeps costs down by leaving out components that can be reused from your existing engine or are easily sourced separately, without cutting any corners on the actual remanufacturing process itself. Every long block is machined using Rottler equipment, some of the most advanced machining technology in North America, resulting in tolerances that exceed original OEM specifications. Inside, you're getting all new pistons, rings, bearings, gaskets, seals, valves, springs, hardened seats, stem seals, and cast guides, along with Total Seal gapless piston rings standard. DFC also builds in improved gasket sealing methods specifically targeting the common leak points this early Duramax platform is known for. Whether you're keeping a work truck running or restoring a reliable daily driver, this long block gives you real remanufactured quality without paying for a full engine package.

Precision Machining Built Around Early Duramax Reliability

The DFC Diesel KORE660104LB7LB is a remanufactured long block engineered specifically for 2001-2004 GM Silverado and Sierra 2500HD and 3500HD trucks equipped with the 6.6L Duramax LB7 engine, compatible with both automatic and manual transmission applications. Every long block is machined using Rottler equipment, delivering tolerances that exceed OEM specifications throughout the build. The engine includes all new pistons, rings, bearings, gaskets, seals, valves, springs, hardened seats, stem seals, and cast guides, and comes standard with Total Seal gapless piston rings along with improved gasket sealing methods in the areas most prone to leakage on this platform. The long block ships as a complete short block assembly with the cylinder heads included, along with a complete top end gasket kit and silicone to finish the installation. It's worth noting this long block does not include the front cover, rear cover, oil pump, upper or lower oil pan, oil pickup tube, rocker arms, pushrods, or valve bridges, since these are commonly reused or sourced separately by the installer. Every engine is manufactured in an ISO 9001:2015 certified facility and backed by a 1 year, unlimited mileage manufacturer warranty.

Fitment: 2001, 2002, 2003, 2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7

Notes:

  • Does not include front cover, rear cover, oil pump, upper or lower oil pan, oil pickup tube, rocker arms, pushrods, or valve bridges
  • Component brands may vary by build based on parts availability, cannot be specially requested
  • $500 shipping charge/$2,800 core charge 
  • Engine shipping crate must be returned with core engine for full core credit
  • Manufacturer warranty: 1 year, unlimited mileage
  • Oil cooler replacement highly recommended, mandatory if prior engine had a bearing failure
  • Injector replacement highly recommended on higher mileage or contaminated fuel engines
  • Turbocharger replacement recommended over 125K miles, mandatory if shaft play present or engine was dusted
  • Water pump replacement highly recommended if engine has over 125K miles
  • Evans Waterless Coolant recommended upgrade for corrosion and boilover prevention
  • This product cannot be shipped to California

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