2011-2016 Duramax 6.6L LML Essential Reman Long Block

The Essential Long Block is D&J Precision Machine's cost-effective replacement engine for 2011-2016 GM 6.6L LML Duramax trucks. Each engine is fully torn down, CNC machined and rebuilt with new Tier 1 pistons and rings, remanufactured heads with L5P-style valve stem seals, Tier 1 MLS head gaskets and a keyed crank and cam. It is a focused long block that lets you reuse your external parts, built for daily drivers, tow rigs and work trucks, and every engine is tested in-house before it ships.

• Remanufactured Long Block: Fully rebuilt to D&J Precision Machine specifications for a reliable replacement engine.
• Precision Machined: CNC blueprinted, bored, honed, and deck surfaced for precise cylinder geometry and proper piston fit. Each crankshaft is checked for straightness and size and repaired as needed.
• New OEM-Spec Tier 1 Pistons and Rings: Provides a high-quality piston and ring package for proper fit, sealing, and consistent engine performance.
• Remanufactured Cylinder Heads: Resurfaced and fitted with recut valve seats and new valves for proper sealing and reliable valve operation. The upgraded L5P top-hat valve stem seal design helps prevent valve seal failure and improve long-term durability.
• Tier-1 Head Gaskets: Provides reliable cylinder sealing to help address common LML head gasket failure.
• Keyed Crankshaft and Camshaft: Addresses a known failure point by providing positive mechanical retention between the shaft and gear, helping prevent unwanted movement and related component failure.
• New Bearings and Thrust Washers: Restores proper internal clearances and supports reliable engine operation.
• New Valves: New high-quality valves provide reliable sealing and consistent valve operation for improved long-term durability and performance.
• New Valve Springs: Restores proper valvetrain operation and performance.
• Precision Assembly: Critical engine dimensions and clearances are verified throughout the build for consistent quality.
• In-House RMC Engine Testing: Before shipment, every engine is mounted on D&J's dynamic engine test system and rotated at speed while sensors measure oil pump pressure and volume, cylinder compression, and cooling system integrity. This lets D&J catch internal issues in-house, before the engine ever reaches your truck.
• Built for Everyday Use: Designed to provide reliable performance for everyday driving, and towing applications.

• Rocker assembly
• Upper gasket kit
• Lower gasket kit

Approximate installation time: 25 hours.

A refundable core charge applies to this long block. The core deposit is refunded once a complete, rebuildable core is returned and accepted by D&J Precision Machine.

24 months / 100,000 miles parts and 24 months labor through D&J Precision Machine. For warranty claims or issues, contact D&J Precision Machine directly at 740-297-7223.

The D&J Precision Machine Essential Long Block is a replacement engine solution for 2011-2016 GM 6.6L LML Duramax applications. Each engine is completely disassembled, cleaned, inspected, precision machined, and rebuilt to D&J Precision Machine specifications.

The block is precision machined and matched with OEM-spec Tier 1 pistons and rings as required to achieve proper fit and performance. Cylinder heads are inspected and resurfaced with recut valve seats and new valves. The upgraded L5P top-hat valve stem seal design helps improve valve sealing and long-term durability. The engine is assembled with Tier-1 head gaskets and all-new bearings, thrust washers, lifters, valve springs, and freeze plugs.

Each engine is measured and tested in-house using D&J Precision Machine’s RMC ETS test equipment before shipment. The engine undergoes a controlled test sequence to verify key operating conditions, including cylinder compression and coolant testing. This in-house testing allows D&J to identify potential issues before the engine leaves the facility, providing an additional level of quality control and helping ensure the completed long block is ready for installation and service.

The result is a professionally remanufactured LML Duramax long block designed to provide dependable performance for everyday driving and towing applications.

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