KORE6604505LLYSOALBCC Kore Series Speed of Air Callies Crankshaft Long Block (STD/Auto)

Features:

• Upgraded Callies Compstar-Durastar crankshaft included
• Deep DuraCase nitride treatment for durability
• Drilled rod journals for reduced inertia
• Accepts OEM flywheels and flexplates
• New Mahle pistons, main and rod bearings
• Total Seal gapless piston rings
• New valves, seats, and guides
• Machined to OEM or better specs
• Built in ISO 9001:2015 certified facility
• 1 year unlimited mileage parts warranty

Addressing The Duramax's Most Catastrophic Failure Point

Ask any Duramax owner about the scariest failure on this platform, and a broken factory crankshaft usually tops the list. The DFC Diesel KORE Series Speed of Air Callies Crankshaft Long Block was built specifically to take that risk off the table, pairing an upgraded Callies Compstar-Durastar crankshaft with the value focused Mahle component package that defines the Speed of Air line. The crankshaft features a deep DuraCase nitride treatment for enhanced wear resistance, along with True Form fillet radii across every journal to reduce stress concentration under load, and drilled rod journals for reduced inertia and easier balancing. Because it retains OEM stroke, journal diameters, and accepts OEM post and flange bolts along with OEM flywheels and flexplates, this crankshaft upgrade drops in without forcing you to source specialty supporting parts. This long block gives 2004.5-2005 GM Silverado and Sierra 2500HD and 3500HD owners genuine bottom end strength alongside new Mahle pistons, Mahle main and rod bearings, and Total Seal gapless piston rings, all at a more accessible price point than DFC's full standard build.

Callies Engineering Paired With Genuine Mahle Components

The DFC Diesel KORE6604505LLYSOALBCC is a remanufactured long block engineered specifically for 2004.5-2005 GM Silverado and Sierra 2500HD and 3500HD trucks equipped with the 6.6L Duramax LLY engine, built around an upgraded Callies Compstar-Durastar crankshaft in place of the factory unit. This crankshaft is constructed from hardened 4340 steel with a deep DuraCase nitride treatment, drilled rod journals for reduced inertia, and True Form fillet radii polished to a 6Ra or finer finish across every journal. The crankshaft maintains a 3.898 inch stroke with OEM journal diameters and width, uses a dual keyed damper fit, and includes lead-in oil holes at the main bearings for improved cold start oil flow to the rod journals. The long block assembly includes new Mahle pistons, new Mahle main bearings, and new Mahle rod bearings, paired with Total Seal gapless rings for improved sealing compared to standard ring designs. New valves, seats, and guides are installed during the rebuild, along with new front and rear main seals, and every component is professionally machined to meet or exceed OEM specifications. The KORE Series is manufactured in an ISO 9001:2015 certified facility, and unlike DFC's standard engine line, it carries a 1 year unlimited mileage parts-only warranty that applies to both personal and commercial use.

Fitment: 2004.5, 2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Notes:

• Built with an upgraded Callies Compstar-Durastar crankshaft, not the factory unit
• Crankshaft retains OEM stroke, journal diameters, and accepts OEM flywheels/flexplates
• Warranty is parts-only, 1 year unlimited mileage, for both standard and commercial use
• 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
• This product cannot be shipped to California

Install Instructions