KORE660104LB7LBSOACC Kore Series Speed of Air Calles Crankshaft Long Block (STD/Auto)

Features:

• Upgraded Callies aftermarket crankshaft included
• Stronger than factory Duramax crankshaft
• New Mahle pistons, main and rod bearings
• Total Seal gapless piston rings
• New valves, seats, and guides
• New front and rear main seals
• 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 aftermarket crankshaft with the value focused Mahle component package that defines the Speed of Air line. Callies has built a real reputation in the diesel performance world for crankshafts that hold up where the stock LB7 crank simply wasn't designed to, especially under sustained load or increased power. This long block gives 2001-2004 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. Whether you're rebuilding after a close call or building proactively before your LB7 ever lets you down, this combination gives you real peace of mind at the one failure point that worries Duramax owners most, without paying for components you don't need.

Callies Crankshaft Strength Paired With Genuine Mahle Components

The DFC Diesel KORE660104LB7LBSOACC 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, built around an upgraded Callies aftermarket crankshaft in place of the factory unit. This crankshaft upgrade directly addresses one of the LB7's most well known failure points, where the factory crank can break under sustained high horsepower or heavy load. 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 to help ensure a proper seal at both ends of the engine. 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: 2001, 2002, 2003, 2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7

Notes:

• Built with an upgraded Callies aftermarket crankshaft, not the factory unit
• 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